Tuesday, August 30, 2011

Final Preparations For Registration

Today, after work, I drove to a vehicle inspection office to reserve a time for the registration. People had recommended a place in Tuusula but after getting there, the price was over 300 euros! I had asked around before and had heard offers of about 150 euros so I decided to call a few places. After a few phone calls, I had an inspections time for tomorrow at 10 am. Cost was about 140 euros. Still expensive but only half compared to the first place.

Now that I knew where drive, I could get the temporary plates. You need to specify every trip you plan to make to get them. Today I needed to visit a friend to adjust the headlamps and tomorrow drive to Vantaa for the inspection.

I got home and started doing the preparations so I could drive the car. I emptied all unnecessary tools and other crap from the car and then bolted the seats back in place. Then I put some other tools that I might need on the way in the car and added some coolant. Now the car was ready to go!

The 15 km drive went without incidents but I did find a bug. The wipers got stuck between the hood and the windshield! They didn't fit between the gap there. I would have to check it out in the evening. Adjusting the lights took about 5 minutes and after chatting a bit, I started driving back home. And another problem appeared: the starter motor still turned slowly when the engine was hot! The heat shield didn't work...

I filled the gas tank on my way home and also noticed that the fan was on. So the fan and sensor were working! Yay! I got home and started the final tweaking. First was the wipers. I had changed the blades and the new ones were a little higher that the original. Now the wiper arm got caught to the hood. The blade retainer was made of plastic so I just cut it a bit until the wipers cleared the hood. Just barely but at least they worked.

Second thing was tuning the hood a bit. It didn't always close properly so I tweaked the locking mechanism. When it worked, I added some window washer liquid and was done for the day. And hopefully ready for the inspection.

Exciting to see whether I get plates tomorrow!

Frame Number

Before I could get the car registered, I needed to add the vehicle identification number (VIN) to the frame. I had borrowed letter and number punch tools for this and went to work. The number should be on the passenger side front frame so I decided to put it in the wheel well. I removed the wheel, cleaned the frame a bit and started hammering. It was quite difficult to get good lettering because there's not much room to swing the hammer but at least I got some kind of markings to the frame. I hope it is acceptable.

Next I cleaned some of the wiring in the engine bay. The AC wires had not been taped up yet so I did that. I also noticed that the heater motor did not work any more. It was time to dig out the multimeter again. I tested the wires and it seemed that the wires coming from the AC control panel were cold. Most likely some connector had come loose when attaching the center console. *Sigh* I guess I need to remove the cover panel and take a look. Luckily I don't have to remove the whole console.

Final job for the night was adding the other wheel well carpet to the trunk. Again I removed the interior panels and seat belt and placed the carpet in. I wonder who had cut the carpets because the shape of this one was all wrong. I trimmed the carpet a bit, cut a few holes for the belt fasteners and put everything back in. Finally a complete carpet set was in!

Only one more mandatory fix left before I could try to register the Corvette! The headlamps were pointing in random directions and would have to be adjusted. The problem was that I didn't have an alignment tool so I would have to get temporary plates again and drive the car to someone that did...

Monday, August 29, 2011

Garage Cleaning

I was finally getting car parts that had been sitting on my shelves for nearly two years back where they belonged. So it was time to do some cleaning. My garage is really small and the Corvette just barely fits in it. I need to park it so close to the right wall that you can't move on that side of the car. The length is also so tight that the garage door just barely closes. I need to back the car out to the yard to do any work.

Now that I had the interior back in the car, I could clean the garage a bit and get more room in it. While doing this, I made a discovery from the storage room: the rear wheel well carpets were there! I had forgot about them and they were covered by other crap so I hadn't found them before.

After cleaning, it was time to continue the project. First issue was the dash pad. I unscrewed it, reconnected the light bulbs and started testing the lights. The indicators had stopped working so I began from those. Quickly I found the first problem: a fuse had burned. I replaced it and tested again. Now the left side indicators worked fine but right side front and back indicators didn't.

I removed the light bulbs, which seemed to be fine so I dug out my multimeter. All the connectors showed normal voltage. Strange. I couldn't find anything wrong from the wiring so I desided to replace the bulbs just in case. And after this everything worked perfectly! Well, that was easier than I had feared.

Next I desided to bolt in the valance panel and spoiler. Another relatively simple task. First I had to attach the retainers but then bolting the panels went without problems. Job done.

It was getting late but I decided to do one more thing: place one of the missing carpets in the car. I unbolted the rear quarter panel, seat belt cover and the seat belt retractor itself. Then I needed to cut a few holes to the carpet for the retractor bolts and put everything back together. The trunk was much nicer now!

Only a few more things left before registering the car!

Friday, August 26, 2011

Details And Dash

Next on my list were a bunch of small details. First I installed the exhaust gasgets. The headers were blowing a bit after the collector because there were no gasgets there. I removed the bolts from the flange, installed the gasgets and put the bolts back. Small and fast task.

While under the car, I also installed the starter motor heat shield. When the engine was hot, the starter turned really slowly. When cold, it worked fine. Most likely this was because the headers went a few centimeters away from the starter and heated it up. Hopefully the next hot start would be easier.

Then came the door weatherstrips. First I tested the weatherstrips to see how they fit. Things seemed fine except that the idiot that had painted the car, hadn't even removed all the old screws that held the weatherstrips in place. Some of them were broken or rusted in place but still. I spent a few hours removing them all by drilling or screwing them out with pliers.

I had bought Bison Liquid Rubber for attaching the weatherstrips and the instructions said I should roughen the paint before using it. So I checked the routing of the weatherstrip, sanded the door a bit and finally applied the glue. I proceeded in short sections by first adding glue, then pressed the weatherstrip in and finally added some tape to hold everything in place.


I then left the glue to dry for a day and removed the tapes really carefully. At first I needed to really slam the door shut but after a few days of settling, the weatherstrips found their place and hopefully wouldn't let water in anymore.

After waiting for a few weeks, I finally received the last item for the dashboard: the nut for the headlight switch. I also got the valance panel retainers so now I could get the car ready for registration. Hopefully...

I screwed the switch to the dash panel and went to put it in the car. And many a curses were uttered! After screwing in every panel except the left lower dash pad, I was a bit worried if it would fit in. And it didn't. It took me a complete evening of raging and fighting to get the panel in place. First I needed to unscrew the dash, then remove the windshield padding, next the speaker etc.

When the panel finally went in between the steering wheel and dash, I had to reconnect the speaker through a tiny gap. Then attach all the gauge lights by lying on the floor. Next were the speedo cable and tach wires. And finally the headlight switch wires and vacuum hoses went in. I'm not sure what was the problem but the switch connector wires were way too short so I had to build an extension for them.

Finally, late in the night, I could screw the panel in place and test it. And some more naughty words escaped my lips. The brake warning light and high beam warning light bulbs had come loose while manhandling the panel in place and for some reason the right indicator light was on constantly. Perhaps I had connected the wrong light in while working blind on the floor. There was no room to get my hand behind the tachometer so I would have to unscrew the panel again to put the bulbs back in. But that would have to wait for another day as now I really needed a beer.

And that's it. This blog has finally catched up the current situation. From now on I'll try to write an update when I get something done. There still are a few things on my list before I can register the car. Hopefully I get them all done next week.

Thursday, August 25, 2011

Fan Temperature Sensor

For the fan to work, it needed a temperature sensor. I had bought a simple sensor and a fitting to place it in the lower radiator hose. I would need to drain the coolant, cut a piece out from the hose and add the aluminum fitting in. Then I could just screw in the sensor and attach the wires.


But I ran into a problem. The largest fitting I could find was 42 mm in diameter but the hose was 48 mm. No matter how much I searched and asked around, I couldn't find a larger one. Next I thought about building one myself. Should be simple to buy a short pipe, drill a hole to the side and weld in a nut. But I didn't have a welding machine...

I called US-Parts in Helsinki and they had the solution. They were selling a Hayden Automotive fan sensor model 3647 that I could use. It had some good and bad sides. The good news were that now I wouldn't need to drain the coolant, cut the hose and that I could adjust the temperature settings. The bad were that I would need to add new wiring for the sensor and that I didn't know how accurate the sensor was when it wasn't actually touching the coolant. Despite these, I bought it.


I attached the control box to the driver side fender and checked the wiring. Luckily I could use almost all of the wires in my own harness and only needed a few new ones. Here's how I connected them up:

  • Red wire - permanent power: I still had room in my power junction so I connected the wire directly to it.
  • Black wire - ground: There was a large ground wire meant for the actual fan near the sensor so I split it up to two wires and used the other for grounding the sensor.
  • Yellow wire - ignition: I had an ignition wire already in my harness as I had meant to use it to power the other fan sensor. So I just connected it to the new sensor. Oh, and originally the ignition signal was spliced from the windshield washer power wire.
  • Green wire - AC power: This signal would force the fan to turn on when AC was on. As the AC had been removed from my car, this wire was unused. This wire could be used if I'd like to override the sensor with a switch later.
  • Blue wire - fan 1: Connected directly to the fan itself.
  • Orange wire - fan 2: Not connected as I only had a single fan.
Final bit was to attach the sensor itself. The instructions said that I should place it as close to the upper hose as possible. I found this a bit strange as shouldn't the fan be turned on when water exiting the radiator gets too hot? If air flow by itself is not enough to cool the engine? Isn't this the reason that normally fan sensors are in the lower hose? Based on this I installed the sensor as low in the radiator as the wire permitted. Unfortunately this was not very low as the wire was so short. Oh well, I could tune the fan activation point from the control box so it was OK.

And now I had a complete electrical fan control system in my car. I just needed to test it and adjust the fan activation point.

Wednesday, August 24, 2011

Engine Bay And Electrical Fan

I needed to install the expansion tank and electrical fan to the engine bay. The tank just needed to be bolted in place but the fan needed a custom bracket. I started from the tank.

The right side inner fender in my car was in pretty sorry state. Not broken but dirty, faded and paint was stripping off. I didn't want to add the tank before tidying it up a bit. So I sanded the old paint with some sandpaper and cleaned the surface. Then I applied some flat black paint to it. I did this with a brush because I didn't want to cover everything up for spraying.


The fender looked much cleaner afterwards. Also note the near-factory radiator support brackets! For some reason they were loose and didn't hold the radiator in place. While testing the car we just tightened everything up with a piece of wood :D It would have to be fixed later. Most likely the bracket is just a bit in the wrong position. Then I just bolted the expansion tank in, connected the hoses and filled the tank with coolant.

Then it was time to tackle the fan. I bought a fan that had a large shroud around it. Its size was almost perfect for the original radiator and I hoped that if would cool the water more evenly than just a basic fan. The shroud had a groove at the bottom and couple of bolt holes on top. I would need a support that would fit in the groove and another for bolting the top to.

I decided to use the original fan shroud attachment positions for my own brackets. So the first thing to do was to cut a piece of cardboard and see how large my brackets needed to be. After getting my approximate measurements, I drew the shape on a metal sheet and cut it out. The difficult step was next: bending the sheet without a brake. As I didn't have any real tools for shaping metal, I just squeezed the sheet between two planks and then hammered it to submission.

After a few nights of cutting, bending, hammering and cursing, the brackets were ready. I smoothed the edges with a file and then painted both parts. I wanted them to be matt so I first sprayed three layers of red primer and added four layers of matt black. After the paint had dried for about a week, I also decided to add some clear to protect the paint some more. At least the bottom bracket would need this as it would receive all the water and dirt from the road. I sprayed both parts with a few layers of matt clear and left them to dry.

After a week it was time to put the fan in the car. I checked the brackets and for some reason the clear had turned them really glossy. Perhaps two matt paints make a glossy one? Oh well, luckily the surfaces were quite smooth so the glossy brackets would do.


I bolted the brackets to the car and the fan to them. I was quite happy with the results as everything lined up perfectly. Next needed part was the fan sensor.


Tuesday, August 23, 2011

Rest Of The Interior

After getting the center console in the car, rest of the interior was somewhat simple to put together. When I bought the car, I got a large box of interior parts with it. They had been sitting in storage for nearly two years so my first task was to thoroughly clean and inspect them. I had some Autoglym Vinyl & Rubber Care that I used for nearly all pieces. It returned a nice shine to the old parts.

While going through the interior, I found out that it was far from complete. It was missing the rear wheel well carpets, rear window frame, rear window lower trim, kick panels and center console side trims. And to add a few more, the air ducts to the side vents were also missing. Wonderful when I thought I had all the pieces when buying the car... Oh, and all the pieces that went to the roof were black. I had thought they should be black but later found out that they should be the same color as the rest of the interior...

I started from the T-top center panel as it seemed to be under other parts. Then came the windshield trim. They were simple to screw in but I needed to fiddle with them many times to get everything lined up. Finally I added the sun visors over the trim.

I had noticed the missing kick panels quite early in the project so I had already bought some used ones for my car. They were black but I simply cleaned and painted them to the correct red color. While attaching them, I also noticed that the door sill plates were on the wrong sides of the car. Luckily they were held together by just a few screws.

Then came the rear panels. I started from the roof trim that just screwed in. But when installing the rear quarter panels, I noticed that they should come first as some screws were cowered by the roof trim. The quarter panels were also the most problematic panels in the car. They had some glued metal inserts for screws but both sides had many rusted in screws that I couldn't remove. On top of that, both sides had many broken off screws.

I found a repair kit for the inserts but now needed to get the old screws out. A couple of them were quite easy to remove but some seemed almost impossibly tight. I tried pulling, turning, drilling, shouting, cursing and kicking but couldn't get all of them out. I'll have to see if I can come up more ways to try. Maybe crying? For now I just put the panels in the car without all the screws... Finally I placed covers for the seat belt retractors and the "trunk" was done.

One of the final pieces were the door cards. But of course they had problems as well. The panels are held in place with velcro like retainers. Unfortunately most of the retainers in my doors were broken or full of paint and unusable. So I had to order new retainers and am still waiting for them.

The last missing piece is the left dashboard panel with the speedo and tachometer. I need to attach the headlamp switch first but when doing that, I saw that I'm missing the nut that holds it in place. So, yet again, I had to wait for three weeks for it to arrive from the US before putting the panel in the car.

Monday, August 22, 2011

Center Instrument Bezel

The original bezel in the car was missing the top part that had the air vents. Annoyingly it seemed to be really easy to break if it was bent even slightly. And repairing it was impossible. So I had bought another bezel from an earlier Corvette. This version still had the button for canceling the seat belt buzzer. As the horn was missing from the steering wheel, I desided to temporately use it as horn button. I also wanted to replace the steering wheel at some point so buying the horn hardware would be a waste of money.

I also wanted to add a modern DIN-sized radio to the car. I didn't care that much about original look so the normal position would be used. There are aftermarket versions of the bezel that already have the DIN-slot but they are pretty expensive. The one I bought already had some holes drilled to it so it didn't feel bad to cut it up. If it had been in perfect condition, I would not have used it. So, I used a saw and file to cut a large hole to fit the radio.

While working with it, I also removed all the gauges and cleaned them to the best of my ability. They had some small rust spots on their faces that I couldn't fix but at least the connectors were good. While fighting with the electrical gremlins, the fuel gauge also had let out some smoke. It still sort of worked but for some reason the needle went well over the full tank marking. Maybe I should also replace the gauges at some point but for now they were OK. The clock wasn't working either but for some reason it cost a lot more than any of the other gauges so I could live with a broken clock.

Finally I built a simple switch below the button to act as the horn button. Pushing the button grounded the horn relay and would play the horn. In theory at least because when testing the system, I found out that the relay was not working... Connecting it was simple: I just added a wire running from the steering column connector to the button.

Connecting the bezel to the car was again quite fiddly. I connected a huge bunch of wires and lamps to the gauges and started fighting. Getting the bezel to the correct position was hard but after trying about a dozen times it went in. I quickly added a few screws to hold it in place so it wouldn't fall out.

Radio wiring was also quite simple as all the necessary connectors were close by. I bought a normal ISO connector and searched the needed wires. I would only need 4 wires: permanent 12 volts (pin 4), illumination dimmer (pin 6), ignition (pin 7) and ground (pin 8). Three of these were already in the original radio connector: black for ground, grey for illumination and yellow for ignition. Permanent 12 volts was also near: orange wire for the clock. As the clock was not working, I just used its wire for the radio. The other ISO connector is for the speakers so I just installed those wires and had a working radio!

For testing, I borrowed a cheap Clatronic AR 817 radio from my friend. I wasn't sure if a CD-player would fit in the radio slot so the AR 817 was perfect. It only had an MP3 player from USB card and a radio so it was really short. After installing it, I'm still not quite sure if a CD-player will fit. There is some room behind the unit but not much. I guess the only way to know for sure is to test...

Sound quality is not good by any standard but I'm not sure if it's because of the Kicker DS 460 speakers or the Clatronic. Probably both :D I'll have to try a better radio later. For now the system is good enough for testing as I'm not even sure if you can hear anything from the radio when driving. Or even when just idling the engine!


Saturday, August 20, 2011

Center Console

Then I had to assemble the center console. This meant the parking brake and shifter covers. I figured that I should begin with the parking brake console and tried it on. Quickly I found out that I must first remove the seat belts as they should not be bolted under the carpet. At about this point I started to feel that bolting the seats had not been a good idea as there was no room to remove the belt retaining bolts. *Sigh*, out came the seats once more.

I unbolted the seat belts from the center console, cut small holes to the carpet and bolted the belts back in over the carpet this time. Now the edge of the carpet would go neatly under the console. Placing the console itself was quite simple. I attached the power window switched to it, connected the wires and screwed the console in.

Next was the shifter cover. I feared connecting it wouldn't be so simple. It had a lot of wires and vacuum hoses connected to it. Quickly I found out that removing the trim plate and AC controls made the job much easier. I then screwed the cover loosely in place, connected the wiring and vacuum hoses to the AC controller and placed it back in the cover. Last job was to attach the cigarette lighter wires and couple of lamps to the plate and screw it in place.

A Million Small Things

Now that the car was finally in my own garage, it was time to put it back together and register it. But there was a lot to do before getting to that. Things on my list included:
  • Building brackets for the electrical fan
  • Adding the fan temperature sensor
  • Adding expansion tank for the radiator
  • Adding the valance panel and front spoiler
  • Rebuilding the interior
  • Adding weatherstrips to the doors
  • Adding gasgets to the exhaust
  • Adding heat shield for the starter
  • Build a horn button (original button from the steering wheel was missing)
  • Fix a small oil leak from the driver side valve cover
  • Align the headlamps correctly
  • Align the rear wheels (because of the risers in the spring)
That's a lot of big and small jobs. I started from the interior. When driving home, I had placed some of the panels in the car but now had to take them out again. It seemed that the interior must be assembled in the correct order so I removed pretty much everything. The carpets also smelled a bit musty so I also took them out and washed them with some water and soap. Unfortunately they had some stains that didn't come off but luckily the stains would be covered by the seats.

The drive home had been quite noisy and hot. I hoped that the volume would drop with the weatherstrips and interior but the heat needed more addressing. So I bought some noiseproofing/heat insulating panels. They had glue on one side so I just cut them to correct size and attached to the firewall and floors. Then I put the carpets back and bolted the seats in.


With that out of the way, I placed the air ducts below the dash. Simple job of screwing a few screws and positioning the wiring harnesses better. Lucky that because I had to do it again when I realised that the air vent vacuum hoses were installed in the wrong places...

There is a huge mess of small vacuum hoses inside the dash. Luckily I found a good diagram of them from Willcox Corvette. I checked the hoses and, if I remember correctly, they were all wrong... So out came the ducts. Correcting the hoses was quite fiddly as some of the vents were in really tight places but I managed with only slightly bleeding knuckles. Assembling the interior would be much easier if I had taken it apart myself...

Wednesday, August 17, 2011

Hurry Home Wayward Son

After midnight we returned to the garage for final cleanup and the drive home. When backing the car out, we also measured the exhaust gases. It seemed that the engine was running a bit rich but that should be OK for now. Again my friend drove the Corvette and I followed in the "support vehicle".

This time things did not go as well as before. After driving about 10 km, my friend pulled over and told me that the engine temperature was rising above normal again. He didn't dare to let it go above the red limit so we waited a bit. Oh, and we couldn't get the hood open again! Most likely the hood lock was now in the wrong position as we had tuned it at the garage...

After some cooling we continued but had to stop again soon. My friend said that if driving over 50km/h or driving up a steep hill the temperature started rising. We suspected that the missing valance panel and spoiler meant that not enough air was going through the radiator. So, we continues slowly and got to my friends place at 3 am.

I had been thinking that I would drive the car home in the next day but now it seemed that I would have to drive really slowly. Me and my wife had to be home quite soon so I decided not to drive the car while it was still overheating. It was really disappointing to leave the Corvette behind once more.

But then I got some good news in the following morning. As the temporary plates were good for the whole day, my friend had took the car for a test drive in the evening. He had drove around for an hour and a half without any problems! Maybe there had been an air bubble in the cooling system and it was gone now. Anyhow now I could fetch the car any day! Only I would need to buy a new alternator because the old one was making weird noises, getting really hot and not charging any more. Luckily it had not broken the new battery I had just bought.

Then on 3. of June, 2011 I got myself another set of temporary plates, got on a train and went to get my car home. We connected the new alternator, packed as much stuff in the car as we could and I jumped behind the wheel.

After driving for about 20 kilometers, I again noticed that the temperature was rising above normal. Luckily this was just because I was had been driving on first gear the whole time! Yes, this was the first car with automatic transmission that I had drove for any length...

Along the way I quickly noticed that if I kept the engine RPM below 2000, everything was fine. Above that the temperature started climbing slowly. This meant a maximum speed of about 75km/h. The car really needed new radiator seals and front spoiler! At first I only used smaller roads but after a while went on the highway. Everything went fine and the 'Vette arrived home for the first time!


Finally I could start putting the car together myself and hopefully get it registered as soon as possible!

Tuesday, August 16, 2011

Long Weekend

After getting to the garage, we immediately found a problem: the hood would not open! We pulled the lever, tried using the hole in the wiper pit, pulling the release cable through the alarm switch hole in the fender etc. but nothing worked. Finally we gave up for now as we didn't need to get it open right away.

I started working with the firewall and placed three layers of fiberglass to the bottom of the car and two layers inside. That took care of a lot of holes in the floor. Meanwhile my friend worked with the rear body mounts. The brackets had rotten badly and the body was not really connected to the frame at all from the back. The old bolts had also almost completely turned to dust and broke when trying to turn them. Luckily I had ordered a complete body mounting set with the first delivery so I had all the necessary parts.

Just changing the bushings was not enough. My friend also needed to weld new metal to the brackets. When both sides were done, perhaps the body would stay on the frame when braking heavily :)

After I got the fiberglass installed, I started cleaning the final hole in the driver floor. Like everywhere else, it had been "fixed" by screwing a thin sheet of metal over the hole and then sealing it up with urethane foam. A floor just like Chevy intended...

"Fixed" floor
And what do we have under the metal sheet?
Much better
I wasn't going to use the original seat belts so we removed the pit and just made the floor flat. Much easier and faster to weld. And now we finally had waterproof floors in the car!

Then it was time to tackle the speedometer gear. We removed the driveshaft and pulled the yoke out of the transmission. Next we had to add some support for the transmission so we could remove the frame connector. That allowed us to remove the few bolts keeping casing together. Now the axle was visible and we could install the gear.

When ordering the gear I wasn't quite sure how many tooth it should have. I took one with 10 teeth but later learned that the correct one would have only 8. This meant that the speedometer would show about 10 to 15 mph too much. Oh well, changing the driven gear was really easy so I would correct the error with it after a measurement with GPS. Perhaps I could even change the speedo to show km/h :)

Strangely the gear and the clip holding it in place didn't fit together. The clip was way too wide to fit in the groove in the gear. As the gear was made from plastic, I just trimmed it a bit with a knife until the clip went in. Then the gear was placed over the drive shaft and locked in place. Unfortunately I also noticed that the  yoke seal that I bought was too large. Most likely meant for TH400. After calling a few places I found the correct piece from Soini Car Parts. Phew! Without the correct new seal, transmission fluid would most likely leak out and we couldn't leave the car to the garage.

Reassembling the transmission went quickly now that we had all the parts. We also noticed that the U-joint behind the transmission had been installed incorrectly before. It was little off from the right position. Naturally we corrected this and put everything back in place.

Then we finally had to get the hood open for the oil change. After fighting some time, we finally got it open by loosening the hood bolts through the wheel opening. We checked what was the problem and found that the pin holding the hood release cable had broken off! This was most likely the cause of the strange noise during the drive to the garage. No wonder the locks would not open. We replaced the pin and the hood release cable worked again...

Then it was time for the final small tasks. We poured new oil to the engine and added a few inch risers to the rear spring. Now the exhaust wouldn't hit the ground in every bump in the road...

And then everything was finally done! We couldn't drive the car yet because the temporary plates were for the next day. We went home to relax and barbecue for a while and intended to return after midnight to drive the car back to my friends place.

To The Garage

We did our final preparations for the trip to the garage in the end of April. We attached the heater box so there wouldn't be a huge hole from the engine bay to the cabin, went through some of the vacuum hoses and checked why the speedometer didn't work. And naturally, as always when going through new systems in the car, we found more things to repair...

The vacuum hoses going to the AC control panel seemed to be in fair condition but the hose going to the actual vacuum source was cut near the firewall. I would have to attach it somewhere. I don't know the actual position where it would have been so I guess any vacuum hose from the intake manifold will do.

The speedometer proved to be more problematic. The speedo cable from the transmission seemed to be OK but things were different inside the transmission itself. The driven gear was in the transmission but the drive gear around the output shaft was missing altogether! After some reading around the net, luckily the driven gear installation didn't seem to be as difficult as I feared. We would have to remove the drive shaft, unbolt the rear section of the transmission and pull the output shaft out. Then we could install the gear. I also found an excellent picture explaining the situation.


After I received the missing parts, we fetched temporary plates for the car again and started driving to the garage. It was nerve wrecking to drive the car for the first time since it had gone through engine repair and nearly the whole electrical system had been changed. My friend drove the Corvette and I followed him in another car the 35km journey to the garage. At one point of our drive he called me and asked if something had fallen off the car. He had heard a loud bang from somewhere but everything still seemed to work. I had not seen anything so we drove on. The sound would be explained to us later...

In the end we got to the garage without other major problems. One of the rear lights wasn't working properly but other systems worked fine.


We got straight to work as we had a long list of repairs:

  • Weld the driver floor
  • Fix holes left in the firewall when the old floor had been screwed through it
  • Change the rear body mount bushings and weld in new mounts
  • Add the speedometer drive gear to the transmission
  • Change the oil
  • Add some washers to the rear leaf spring to rise the rear up

Monday, August 15, 2011

Dash Speakers

Before we could drive the car to the other garage, I still needed a few parts for it from the US. While waiting for them, I desided to install some speakers to the car. There should be some plastic brackets for them in the dast, but naturally they were missing. So, I had to build new ones myself.

A friend of mine works in a company that imports Kicker speakers to Finland so I had already bought some 4x6" speakers from him. They were the same size as the originals so they should fit but just needed the brackets. I desided to use fiberglass to make them as it should be a perfect material for it.

First I placed some cardboard to the speaker opening and covered it with foil. This way the fiberglass would not get stuck to the dashboard. Then I cut the fiberglass to suitable pieces and placed down three layers of it.


After the epoxy had hardened, I used a saw to cut out extra material and a file to smooth the edges. I didn't sand the whole thing smooth as it would not be left visible. I did apply some black paint just to hide the bracket a bit. In the end it worked as planned and I had some speakers in the car.


Finishing Up The Wiring

In the beginning of April 2011 I finally had all the new wiring harnesses as the one ordered from Full Throttle Corvette arrived. We got to work and I installed the redesigned headlight harness and my friend placed the dashboard harness in the car.

I had to cut some wires to correct length and solder some fusible links to them. Otherwise my job was just to attach all the connectors and use the hooks in the engine bay to route the harness. The dashboard harness seemed like a huge mess but was actually quite simple to install. Naturally the routing would need to adjusted when installing the interior but for now it went in the car without much pain.

After connecting everything up, it was time to test the system. We decided to do this carefully as every major wiring harness had been changed in the car since it last ran. And one was even completely redesigned by myself! We didn't connect the battery to the system but used a quite low power battery charger for the testing. This way if there were short circuits or some other problems, we would find them without melting the wires.

In the first test we left out all the fuses too and then connected the charger. This didn't cause any sparks or show any visible problems so next we added the fuses and tried again. Still no sparks! :) Then we went through the different systems. Lights seemed to work but there was something wrong with the front indicators. They blinked on the opposite side they should: left when turning right, right when turning left. We checked the system and found that the indicator wires were mixed at the firewall connector. They were correct according to Dr. Rebuilds diagrams but I guess the diagram had an error. We switched the wires and after this the indicators worked correctly. Note that this has been fixed in the wiring diagram in the previous post.

Testing the lights also confirmed that we finally got rid of the front brake lights! Before when pressing the brake pedal, both the front indicators lit up. Most likely this was caused by a splice added to the brake switch. Why? I have no idea! Perhaps it was some innovative safety equipment :)

As no problems were found, we removed the charger and added the battery. This way we could test higher amperage equipment. And we were really happy to find a lot of new working stuff: all lights, windshield wipers and washer, heater blower motor etc. Seems that it helps that the ground wires are not connected directly to the battery...

Then it was time to do the real test: start the engine. We turned the key and nothing happened! Luckily after a quick test we found that the starter solenoid wire was connected to the wrong terminal. We moved it to the correct place and the engine started right up and ran notably smoother than before.

Now we were almost ready to drive the car to my friends work garage and do what we originally intended half an year ago: weld the holes in the driver floor.

Tuesday, August 9, 2011

Redesigned Headlight Wiring Harness

As I mentioned in my last post, I redesigned the wiring in my Corvettes engine bay. Here's how I changed it and why.

Let's start with the why.

While going through the electrical problems in my car, I also learned that the wiring is far from optimal. Not nearly as bad as in the 60's but still there was a lot of room for improvement. I also wanted to add some new electrical stuff to the car and this would be difficult with the factory wiring.

I'm not an expert in car electrics but luckily I found the MAD Electrical web page. They have some great articles about electrical systems in muscle cars. After reading their texts (many times) I had had a pretty good idea what to do. The major problems were:

  • Headlights
  • New equipment


Headlights

Headlights of the -76 Corvette are the worst part of the electrical system. While looking through the Doc Rebuilds wiring diagram, I saw multiple problems. From the lamp itself the feed wire goes to the main connector at the back of the fuse box. From the fuse box it continues to the dimmer switch which selects high and low beams. Power to it is fed from the headlight switch which in turn has a power wire from the fuse box. Next in line is a fuse and then the main power wire from the engine bay and the battery and/or alternator.

Very simple and direct but crappy. First of all this creates a really long wire from the power source to the lamp thus causing voltage drop. This dims the lights noticeably. Secondly this means that all the current used by the lamps goes through the headlight switch causing corrosion in the connectors and might fry the switch. Third problem is the main power wire. A single 10 gauge wire feeds a lot of devices: radio, interior lights, wipers, rear lights, power windows and, of course, the headlights. That could be a lot of current through a single wire.

The simplest way to correct all these problems is to add relays for the headlights. This way a large power wire can feed the relay and the headlight switch just controls if current goes through it to the lamps. This shortens the way from the power source to the lamp, lowers the current that goes through the switch and naturally does the same for the main power wire.

Now, where to connect the feed wires for the relays? This brings us to the other major problem.

Adding New Equipment

I also wanted to add an electrical fan to my radiator. The clutch in the original fan was not working, the fan shroud was missing and the fan drained a lot of horsepower to turn. After removing it, the engine somehow seemed to run much easier.

Replacing the fan dictated that I would naturally need new wiring for it. In addition to the fan, I would also need a new temperature sensor to control it. I read a bit and decided that I would also add a relay for the fan and then control the relay with the temperature switch. If temperature got too high, the sensor would allow current to go through it which in turn would allow current to go through the relay to the fan.

To add all this new equipment, I decided that I need a central power junction from where it would be easy to distribute electricity. It would also be the place where the alternator charge and sensor wires needed to be connected. This way I would know that the junction had a stable ~14 volts. The factory wiring harness naturally also has a similar junction but it is just a splice of two wires inside the harness. It would be difficult to add any new electrical equipment to it.

That's pretty much it. With these guidelines in mind, I drew a new headlamp wiring harness diagram.

New Wiring Diagram


And there it is. Most of the wiring is the same as in the factory harness but let's go through the changes is detail.

  • Junction: There is large power junction marked in the diagram. I also included an example picture how the junction could look like but almost anything will do. I bought a junction meant for car stereo systems and it works great as you can easily screw in more wires. There are two junctions in the diagram but this is just to get more room to draw the wires. If more than one are actually used, they must be connected together. Note that the engine wiring harness is now also connected directly to the junction.
  • Battery: In the diagram the battery is connected directly to the junction. This is the best situation but not necessary. There is already a heavy duty cable from the battery to the starter. Factory harness is connected to the starter positive terminal and this is also what I did. I ran a new 8 gauge wire (with 12 gauge fusible link) from the starter to the junction.
  • Relays: There are three relays in the new harness. For high beam lights, low beam lights and fan. Light relays are controlled by the light switch and fan relay by the temperature sensor. While building the harness, I wasn't quite sure where to place the relays. In the end I placed them far front near the left hand side marker light. After installing the harness I noticed that a better position would be in the fender near the alternator.
  • Fan temperature sensor: The fan temperature sensor needs a constant power source. Connecting it directly to the red wires (ie. battery) is not a good idea because then the fan could be left running even when turning the power off from the ignition switch. Unfortunately there in no wire in the headlight harness that would be "hot" when ignition is on. Luckily the engine harness does have one nearby. The yellow wire going to the windshield washer pump will do nicely. I spliced a connector to this wire and connected it to the temperature switch. This way if the engine is running really hot, I can turn it off and the fan keeps running if necessary.
  • Wiring: I tried to draw the connectors in the diagram in a similar position as they would be in the car. Naturally this is not completely possible but I think you can get a pretty good idea which connector is which from the diagram. Especially if you compare my image with the Doc Rebuild harness diagram. To build the harness, I had the original factory harness with me and I cut all my wire lengths according to it. This way I would get them correct right away. The new wires going to the junction are a bit more problematic. I left them quite long and then cut them when the harness was in the car.

And that's it. It took me a couple of nights to solder the new harness and then wrap it up in tape. Installing it to the car took a few hours and everything seemed to work correctly. Lights are now much brighter and the drain on the light switch should be much lower. All in all, I'm really happy with this new system.


Oh, and just one more precaution: if you actually build a new harness according to these instructions and your car goes up in flames or some other damage occurs, do not blame me. You do need to know something about car electrics before trying this stuff :)