Graham's Corvette Blog and Studebaker bits 'n' bobs

One of the trans cooling lines rusted bad enough to start leaking. So I replaced two sections with rubber hose until I buy a new set of lines. I added a bit too much oil to the trans thinking I lost more oil than I did. So it had to go or the oil might start to foam in the trans. I’m using a brake bleeder setup to extract the extra oil.

I used the vacuum pump to suck out the extra oil. Worked a charm. I took enough out so that I would need to add oil when the trans was up to temperature. Which I did.

My old hood release cable that runs across the firewall had begun to fray (the outer cover) so I bought a new cable from a Corvette supplier. It fitted OK, but it kept stretching and would only release the left side. I had to reach under the hood to grab the cable and pull it until the right side popped. I then had to re-adjust it. After doing this four times or so the bracket on the left broke. The cable core also pulled out. When I released the cable tab on the right side it broke off. Seems the tab plastic is too brittle and breaks easily. Also, the cable stretches.

I wrapped up the old cable with dry vinyl (I don’t use regular electrical tape unless I have to since in a short time the glue turns to goop if it gets heated at all!). The old tabs are fine and the cable seems OK. Put it back on the car using the original adjustment hole and it is working perfectly.

Hoist up full height for this job. Good for working underneath, but the hood hits the ceiling so no engine access from the top.

Borrowed this socket from a friend who has an awesome tool collection. There just isn’t enough room to use a 5/8″ wrench without removing the spare tire and the whole spare tire assembly from under the rear.

Definitely a tight spot to get at.

A selection of tools to take with me under the car. In the end it came off with just the socket long extension and the ratchet.

The leaking rear shocks are pretty obvious. Same for the front so I expect that is why the car gets a bit ‘squirrelly’ when going over bumpy spots like railway crossings and rough bridge sections.

Using this ‘sucker’ I was able to get out about 1.5 quarts of oil from the differential.

I used this slender bottle with a squirt top to get the fluid into the diff. I put 4 oz of limited slip additive into about a pint of 80/90 hypoid gear oil and put that in first. after I was able to get another quart or so of oil before it began to overflow.

The oil from the diff was very black compared to the new oil colour (upper left).

Job done, but there is still about a pint of old oil in the diff. I’ll run it for the rest of the summer and then change it again. That should get rid of most of the old oil.

After a repair to the trans cooler lines (actually rusted through and began to spew oil everywhere!) I took the Chevy for a test drive and the chatter on sharp corners is gone 🙂

The extreme graphite spray didn’t work so I decided to try white lithium grease. First a spray to get inside the coils and then a liberal smear of grease on the outside. When re-installing the cable I ran it back and forth and spun it around. I noticed it grabbing a bit when I was spinning it. So that may be the problem – a bad casing. Underneath I pulled the cable casing back towards the trans giving it a bigger arc as it curved into the trans case. If this doesn’t work I’ll replace the cable and case as a unit. Maybe over the winter.

The window washer isn’t working. Time to pull it. The washer bottle is hidden beneath the left fender. It is in two parts – a neck and the main bottle. A bit of a bear to get at the mounting screws. I removed the neck and was able to twist the bottle around so I could get at the motor and electrical connection. There is no room between the fender top and the power brake unit to get the bottle out and I don’t want to remove the master cylinder and possibly damage a brake line moving it out of the way.

The little pump motor was seized. I pulled it apart and was able to clean up the motor, but it really didn’t want to work all that well. I can get a new unit from Car Quest for about $20 so a no brainer!

Time to open up the door again and adjust the window so it meets the rubber at the top and back of the body. I needed it to go up and back about a 1/4″, but no luck. The motor spins free before it reaches the top. Seems the plastic gears are stripped.

I need to remove the power window regulator unit and see what needs to be replaced. I checked with Corvette Depot and there are lots of repair parts – good thing about restoring old Corvettes is that virtually any and all parts are available.

The gap at the top of window is about 1/4″. I can live with that for the rest of the driving season.

Next I’ll be checking the diff fluid level and tomorrow I take it back to the alignment shop for more fine tuning.

All dash lights replaced by LED units and working. The brake warning light is still an incandescent bulb as I couldn’t tell which side was ground to test it on the printed circuit board. It’s bright enough and is not used for long periods.

The new tach board and filter works, but the extreme graphite I used on the speedometer cable didn’t. the needle is more jumpy than ever!

The old tach filter registered 30 ohms where it should have been only 15. It may have been the problem. I’ll save the old tach board to use should the new board fail. I understand that some boards are made in China and are not reliable.

Before I replaced the clear plastic instrument cover I gave it a cleaning with Novus plastic fine scratch remover. It also cleaned out the fogging. I have also used it on modern car headlights to keep them bright.

I replaced the missing parts for the horn in the steering column and installed the new horn I got from Corvette Depot. It works fine, but I’m a bit disappointed as it is a universal brand with an adjustable flat mounting bar. It still fits OK. I would have liked an original style with the correct ‘L’ shaped bracket.

I installed a new headlight overriding valve that sits under the middle of the lower dash on the drivers side. The old one was broken off and I suspect that it was hit by the driver’s leg getting in or out of the car. I almost did it too so I cut it back so just enough of the pull arm was left to do the job. Hopefully I won’t knock it off. If I do I’ll have to buy a new switch and mount it elsewhere.

Next I’ll re-lubricate the speedometer cable and go back to the alignment shop for the 4th time. It still wants to head right and it doesn’t want to return to centre on right turns.

I removed the anti-theft horn. I tested it and it has 9.6 ohms resistance. Checking with the Google teck it seems horns should only have 1 ohm of resistance.

At some point on my test drive one of the anti-theft sensors must have failed and grounded out. This triggered the anti-theft relay which in turn connected the horn to ground via the anti-theft flasher. The service manual shows that the circuit from the battery is through the horn then the flasher, then the relay and then ground. A 20 amp fuse is between the battery and the horn. So I am fairly comfortable that the heavy draw through the horn caused the courtesy lights to flash and the fuse to heat up and finally blow. When I ran the test the fuse got hot to touch after only a matter of seconds.

I just got an email that Corvette Depot have mailed my second horn, ignition switch, lock and door set, and hot water shutoff valve.

Now it’s time to get the dash back together, test the tach, get the horn working and get the console covered and the seat back in place.

Easier to remove the console side panels and work under the dash with the seat out. Easy-peasy with only four bolts to remove.

The short caused the courtesy lights to flash through the anti-theft flasher and then burn out the fuse. I removed the flasher and the anti-theft relay under the console. With them removed the problem was bypassed and the courtesy lights worked without burning out the fuse. Still don’t know where the shorting problem lies.

I used shrink-wrap to isolate all the anti-theft relay leads. I plan to remove all the anti-theft components, but leave the wiring in place.

Dash removal wasn’t too difficult. It was easier with the steering wheel off and would have been even easier if I could have lowered the steering column, but it didn’t want to lower when I loosened the dash mounting bolts.

I need to replace the tach circuit board so it was also a good time to replace all the dash light – some weren’t working – with new LED bulbs. I tested the led bulbs and they do dim with a reduction in voltage. A bit tricky putting them in the dash since they only work one way being diodes. I had to run 12 volts through each bulb’s circuit to be sure they lit properly.

The new tach circuit board comes with three insulating washers, but no instructions on where to use them. I’m assuming on the metal back of the tach to isolate the circuit board – the new board’s contact points are on both sides of the board.

Dash out and easier to get at the headlight and wiper switchs for testing.

Switches out and now the testing can begin to find why the dash lights aren’t working. I don’t think the short is in the dash light circuit as the anti-theft horn relay, etc are all under the courtesy light fuse.

With the dash out it’s a good time to give the speedometer cable a good coating of graphite. The needle had been a bit bouncy.

I tried cleaning around the hood latches, but it just wasn’t working so I opted to remove the latches being careful to mark the edges so that they would go back in the exact same spots.

With the latches out it was much easier to clean. Notice the body plug just left of center at the top. This I believe is how you get the hood up should the hood cables fail. There is a plug on both sides. On the passenger side a screwdriver would be used to lift the latch trip lever and on the opposite side the driver would be used to press down on the latch trip lever. I’ve left the bits of gasket type stuff around a couple of studs to help locate the latch in the exact original position. On the other side I used a dental pick to scribe lines on two edges for the same purpose.

Everything cleaned up and a spray of white grease on all the moving parts of the latches.

The old cable was still working, but it was beginning to fray.

New cables in place and working well. I’ve also brushed on heavy rust check on the nuts and bare metal. May get to paint them later on.

Next: a dreaded electrical short.

Just a quick recap on the valve cover leakage. The cover on the passenger side was leaking badly a the back bottom corner where the oil gathers before draining back down the block to the pan. It was getting on the exhaust pipe, smelling bad and leaving a trail of blue behind the car. On the advice of a local mechanic (Chevy MacDonald!) who is a Chev racer too, I bought a set of 3/16″ composite FelPro cork gaskets.

I have coated both sides of the gasket with anti-seize paste. That way the gasket will come away from the block and the cover without breaking if I have to remove the cover for any reason. The old gasket was a rubber compound and should have worked fine, but…

I use two small removable studs on the lower side to hold the gasket in place and then align the valve cover.

I only use a 1/4″ drive extension with a driver handle to install the valve cover nuts. That way I won’t over-tighten the bolts. I’m also using spreaders under the bolts to distribute the pressure along the cover lip.

Success! Only the lightest misting of oil at the back of the valve cover. After letting the engine cool I again snugged down the bolts again – not as tight as I could, just a bit now that the gaskets are warm and there is some looseness.

Next some parts arrived and I can replace the hood release cross-engine cable.

Painted brackets in place with a new tie-down bolt. I took the opportunity to spray heavy Rust Check fluid on all the surface rust I could see.

Cleaned out years of crud in the well.

New used tire in the well. That’s a 205/70 R15. There’s lots of room in the well so I’m thinking I’ll look for a used 225/70 R15 that will match the tires on the car.

All neatly tucked away – hopefully will never see the light of day!

Next I’ll need to stop a bad valve cover oil leak before I take it for a 100 km trip to the windshield shop.

Back from the alignment shop. They did both front and rear. Took them three tries to get it right so that with the steering wheel centred it would go straight and not veer to the left. Hard to get it right with these old steering boxes.

Borrowed this too from a friend. Better than trying to line them up in the garage or going out at night to some level spot with 20′ of so to a clear wall. I couldn’t think of any spot locally that would do.

First I disconnected the vacuum hoses to the headlight actuators.

That allowed me to manually raise the headlights. They can be pushed up from under the lower grille.

I removed the headlight surrounds to give better access to the adjusting screws. Three of the screws had stripped the plastic mounts – poor setup! I managed to get a fitting on the screw where it extends behind the plastic mount.

First thing is to measure the slope of the floor with this transit device. The dial at the top has level at 0 and plus and minus sides. With it on the floor you look down an opening in the device at a split mirror. The screw on the bottom is used to align the marks so that they are in a straight line. Then you turn the dial on the side until the bubble level in the top sits in the centre.

The plus or minus number reading from the transit is then used to set both headlight aimers. This is the left. The verticle lines are viewed through a split mirrorin the aimer on the other side.

With the aimers in place the headlight screws are adjusted to get the correct readings on the aimers.

The side to side is correct when the alignment bars line up in the view hole (between the two gauges). The up and down is correct when the bubble gauge (far left) in centred. If you can’t get things to line up properly you can use the white buttons to get things lined up. The readings from the white buttons tell you whether the final adjustments are in tolerance. If not then you need to make modifications to the headlight mounts to get it correct or within tolerance.

Final job it to re-attach the vacuum hoses to the actuators.

Headlight surrounds back in place. The headlights will have to stay up until I next start the engine. The Service Manual give directions to manually raise the lights and states clearly that they must not be pushed down. Once the car starts the vacuum system will do it’s thing and they lower.