New Gauges

My fuel gauge had let out a puff of black smoke during my cars electical troubles. After that it has been, umm, slightly unreliable. When there's gas in the tank, the needle shows well over the full limit. When the tank is almost empty, the needle suddenly drops to zero. I hope that the problem is only in the gauge so I bought a new one. Well, used but working...

While at it, I also bought a voltage gauge. I know this model comes to use in the -77 model but I think it's much more useful than the old one. I heard that I'll have to drill a new hole to the back of the gauge panel and run some new wires but that should be pretty easy. I hope...

Rebuilding the Holley Carburetor

Now it was time to rebuild my carb. The model number was 80457-S so it was a basic four barrel 600 cfm street carburetor with electric choke. It was working OK but there seemed to be some problems. We took the air filter off and checked how it was supplying gas. Some booster venturis were working correctly but some didn't atomize the fuel properly. Large drops of fuel came out instead of a nice spray. I hoped that a good cleaning and rebuild kit would fix this.

Starting point

Once again I visited US-Parts and they had the correct rebuild kit in storage. Armed with it, I began disassembling the carb. As this was my first carb rebuild, I searched for good online instructions. I found a few but the one on Chevy High Performances page had the best pictures I saw.

Float bowls removed

Metering block out

Carb disassembled

I didn't really run into any major problems during the rebuild. I took pictures during disassembly so I could reference them while putting the carb back together. I also had a piece of cardboard and I pushed many bolts and other small parts through it so I could get all of them back in the same place. Oh, and that I wouldn't drop them...

When the carb was in pieces, I sprayed it with some CRC carburetor cleaner. This got the dirt off but there was some oxidation on the surface that I could not get out. So the Holley didn't look like new but at least it was now clean.

Stuff in the rebuild kit

One small mistake that I made was that I took the choke cap off unnecessarely. Luckily this video advised how it should be set back. Rest of the assembly went quite smoothly. I just compared the old gasgets to the new ones in the kit and put everything back together. Finally I sprayed some lubricant to all the the joints and other moving parts and the rebuild was done!

Carburetor rebuild done!

Now I'll just have to test the carb after getting the engine back together...

Intake Manifold Out

My friend visited during the weekend and advised me on how to correctly remove and install the distributor. We removed the distributor cap and marked the position of the rotor to the firewall as it happened to be pointing straight rearward. Then it was easy to pull out the distributor and remove the intake manifold.

Everything seemed to be OK inside the engine so I just covered it up so no dirt would get in. My friend took the manifold to a machine shop so they could plane the thermostat housing and media blast the old paint off. I'll paint it again when I get it back.

Next I will rebuild the carburetor.

Opening the Engine Again

To prepare for the coming projects, I decided to start by opening the engine. I labeled all the hoses and plug wires and got to work. First to come off was the carb. I disconnected the hoses while being careful not to spill any fuel and removed the nuts holding the carb in place. With the Holley in hand, I drained most of the fuel inside into a cup and left the rest to dry out.

Next were the valve covers. They were simple to just screw out and remove. Then I had to remove some of the cooling liquid so it wouldn't spill out while removing the intake manifold. After getting about 5 liters out, the water level was low enough and I removed the upper radiator hose and thermostat. I didn't remove the manifold yet as then I would also need to remove the distributor. I wasn't quite sure how to do that correctly so I'd do it with a friend.

I was on to a good start.

Winter Plans

I couldn't drive the Corvette any more so it was time to concentrate on projects I would do during the winter. All the major jobs were now done but there were a lot of smaller things and cleanup left to do. I went though my work list and it looked like this:

1. Sealing the windscreen.
2. Stopping a small leak from the thermostat housing. The intake manifold had corroded a bit and needen planing.
3. Changing the valve covers.
4. Cleaning the carburetor. It was not atomizing the fuel properly but hopefully would get better with a rebuild kit.
5. Changing the broken fuel gauge.
6. Fixing the passanger side window motor.
7. Buying the missing interior pieces.
8. Fixing and cleaning the spare tire cover.
9. Changing the steering wheel.

 That should keep me busy during the following months...

Lowering the Corvette

The front of my car had been too high as long as I had had it. The stance was plain wrong. Now it was time to correct at least part of that. I thought about buying lowering springs but decided to try the free option first: cutting the current ones shorter.

I began by measuring the current height of the fender in each corner. The results were:

- Front left: 74,5cm (29,3 inches)

- Front right: 74,5cm (29,3 inches)

- Rear left: 71,5cm (28,1 inches)

- Rear right: 73cm (28,7 inches)

It was surprising to see that the passanger side was higher in the rear when compared to the driver side. This would only get worse with the driver. I would have to tweak the suspension in the rear too.

Then it was time to go to work. I jacked the car up, removed the wheel and unbolted the brake caliper. I didn't want to disconnect the brake hose so I used some zip ties to hang the caliper from the fender. Next I removed the sway bar bolt so the lower control arm could swing down freely. Then came the ball joints. I jacked the lower arm to take the pressure off the upper joint. Now I could loosen the bolt but didn't remove it yet. Lowering the jack caused pressure on the joint and, after spraying it with some WD-40, it snapped out by itself.

The lower joint proved to be much more difficult. After fiddling with it for a while, I realised that perhaps I could get the spring out without removing it at all. So again I used zip ties to hold the spindle in place and just lowered the control arm carefully. The final piece holding the spring was the shock absorber. Once more I jacked the arm, removed the shock and was ready to get the spring out.

The spring was still a bit too long to get out easily. I used a spring compressor and finally got it out.

I cut the spring with an angle grinder and then it was time to put it back in the car...

Assembly was much easier than the disassembly. The spring was easy to place back and then I just jacked the lower arm up again. I did it carefully so I got the spindle to the upper ball joint. After adding the nut, there was no fear of the spring shooting out. Replacing the rest of the parts went quickly and the first side was done.

The driver side was done the same way. Only problem was that this time the upper ball joint was badly stuck. It just would not loosen with a hammer so I soaked it with WD-40 and left it for a night. In the next day it had popped out by itself. Strong stuff...

When both sides were back together, I took the Corvette for a short trip around the block so the parts could find their places again. It was quite slippery as the streets had frost on them. I survived and measured the front again. The result was 70cm (27,6 inches) so cutting a single coil dropped the front 4,5cm (1,8 inches). The difference was easily noticeable even behind the steering wheel and from the outside the car looked much more balanced.

Dear lord that's a bad quality photo...

After taking the test drive, it was time to park the car for the winter. I reported it out of traffic and started planning for the fixes I'd be doing during the long winter months...

Loose TH350 Shifter Shaft

UPDATE 10.01.2013: Seems that the loose bolt was not the only problem: Transmission fixing

There had been a problem in my transmission for a long time. I could not force it to first gear with the shifter. I tried adjusting the shifter cable many times but it just did not work. The shifter lever in the transmission felt somehow loose when turning it by hand and just didn't go to first gear. I searched the net for possible causes and found that a loose nut at the inner end of the shifter shaft could be the problem. Oh well, at least that's pretty simple to check and I needed to change the oil and filter anyway.

Unfortunately I had to work in my really small garage again. To get some room under the car, I bought a pair of ramps. With them, I had just enough space to remove the oil pan. So I drove the Corvette on the ramps, added some wedges behind the wheels and got to work.

I drained the old oil to a container and removed the oil pan. It was exiting to see what it would look inside the transmission. The last time that I opened it up with my friend, it had probably been standing for a while. We were a bit worried how much crap had been stuck in the fluid passages and if it had loosened up after the car had been driven for a few hundred kilometers. The oil didn't seem too bad but there was some crud in the pan. The magnet was clean so at least it was just dirt and not metal.

I cleaned the pan and removed the old gasget. Next it was time to crawl under the car again and check the filter. I removed it and couldn't see any dirt. Hopefully most of the crap was now out of the transmission.

Finally I got to the part that I wanted to see: the nut at the end of the shifter shaft.

I tested the nut with a wrench and it did feel a bit loose. There was not much room but I could turn the wrench enough to tighten it. I tested the shifter lever and the play was gone! Perhaps the transmission was now fixed!

It was time to put the transmission back together. I screwed in the new filter, used some silicone to keep the new pan gasget in place and finally bolted the pan to the car. Lastly I filled the transmission with new oil and took the car for a test drive.

And what a difference this small fix made! The shifter was no longer loose and the transmission was much quieter. Previously there had been a jerk and clank when changing gears between reverse and drive. Now the shifts were smooth and quiet. It was hard to even notice when the transmission went in gear.

I still could not get the first gear activated as I had forgot to adjust the cable. While doing that, I noticed a small mistake. When tightening the shaft nut, it had turned the lever a bit. This meant that the cable had to be adjusted to its maximum limit and even that was barely enough. I still could not always get the shifter to first gear. It worked about half of the time.

Oh well, I'll have to tighten the nut again during the next oil change. At least the transmission works much smoother now.