1989 C4 Functional Restoration

[SirReal63]

I am interested in duplicating my CorvetteForum build thread on this old car, as a backup in case something happens and I lose over a years worth of work there. I have done several build threads over the past couple of decades, all but two have gone away with the forum going away. This place is stable and unlikely to go away and I seem to spend as much time here as anywhere else.

If there is any interest in seeing my obsessive disorder on restoration in the cheapest way possible, I will dupe it here if I can figure out an easy way to copy it without messing it up.

 

[Big Mama]

There are lots of Vette enthusiasts here. Copy and paste my man. If it’s not acting right on your phone do it on your computer.

 

[SirReal63]

Thanks, it isn't a phone problem, but a BBS software issue, I use my PC, I have a phone, I look at it at least once a day.

This will be a functional restoration, not a Concourse restoration. I will refurbish what I can rescue instead of just buying new or re-pop. The value of these cars just does not warrant a full on restoration.

I have been wanting a C4 since 1983, it didn't happen since there wasn't an 83. When I saw my first 84 I wasn't exactly "in love", more like eh, technological advancement I can do without, that changed with the L98 which I was truly impressed with. I got my first real job in 1976 doing whatever my mechanic boss wanted, usually that meant under a car doing what his fat old body didn't want to do. I had just turned 13 and was actually hired to clean dead alternators and starters and rebuild them, which was my boss's real business. The time I spent there was educational, though my family had been drag racing since the early 60's my Dad wasn't much of a teacher and the mechanic that hired me was a good friend of my Dad's. I learned a lot, in fact I can count on one hand the number of times I have hired someone to work on my vehicles. I am not a mechanic, my career was as far from that line of work as imaginable, but I still enjoy turning wrenches when have time. I have restored many vehicles over the years, never show quality but good driver quality. This brings me to the C4, a car I have wanted for a long time but never bought for some reason. Having just sold my restored 1994 F350 4wd CCLB IDI Turbo 5-speed I needed something to keep my hands busy. (Not really, my wife and I are retired and have a small hobby farm with the 3500 sq ft 2 story Barndo I built with my own hands, I stay plenty busy.) Time to find another project.

I have been searching for a C4 for over a year now, I had decided on a 91 with a 6 speed. Turns out that is a hard find, it seems a lot of people want the L98 with the updated interior and exterior, not just me. I found several but the condition was not good or the price objectionable. I found one here in Texas but the transmission was a huge question mark, I did not want to be dealing with needing a rebuilt ZF right off the bat. The rest of the car was in decent shape but owned by a kid and I avoid buying kid owned vehicles, I was a kid once, I know what I did. The next possible option was an 89 or 90 but it was mostly the same story, too expensive or in too bad of shape. I was trying to talk myself into flying to Vegas for a beautiful 89 six speed car that had a lot of performance goodies on it but driving back 1300 miles with an untested car was asking a lot, and the car owner agreed, he and my wife eventually talked me out of it. I kept looking and one turned up 30 minutes from the farm, a, 89 six speed convertible. I wasn't looking for a convertible but I also wasn't not looking for one. The price was the same as the one in Vegas but the condition a little worse. I did the math, a flight from Austin to Vegas, gas, hotels, tolls and the huge question of if the car would make it made the decision. It was vastly cheaper to get the one I could drive home and put that extra money into the car, both needed interior work and paint work. Turns out the vert was a good buy, mostly. The engine is strong and the tranny shifts right, just a little sloppy. I should not have to pull this engine, a huge plus.

Here is what I started with...

 

[SirReal63]

The good, and there is some good. One of the 6 previous owners loved and cared for this car, perhaps more than one, but at least one. When I started working on the convertible top, which is original including the rear vinyl window falling out of it, I noticed a huge sub woofer box and 6x9's taking a lot of space. Somewhere in the late 90's a really nice and expensive stereo system was installed. There was a Kenwood KDC-PS7009 head unit, a Rockford Fosgate Punch 360.6 and Boston Acoustics drivers, front and rear. This was excellent equipment at the time and everything worked except the head unit. I removed the huge box, all the wiring started over. The top just barely fit so the box and sub needed to go. I moved the amp to the rear wall, the 6x9's to the cubby holes after removing the Bose pieces that were still there. Looks much better, and neater with actual room to put the top and/or the usual small overnight bag.

The amp was kind of a big deal in the day, it had configurable crossovers that could be adjusted with changing the resisters on the X-Cards. Low tech today but not when it was made.




I did not clean the carpet, it will get replaced with "something" before long.

 

[SirReal63]

The car itself is nothing special, no special handling packages but it does have tire pressure monitoring that does not work. It is a late year model build, with a few nice features. I really wanted a better rear axle ratio, but the 3:33's will be just fine.

 

[SirReal63]

The paint is great from 75' away but closer and you start to see the flaws. At some point it was repainted...mostly. The hood and rear of the car had been repainted but somehow the doors were not. How does that even happen? I do not understand the decision to not paint the doors, but they were not painted. The paint job were it was repainted was not very good work. There are bubbles, cracks, orange peel and a few whiskey scrapes and bumps. These will need to be fixed and I have never done auto paint in my life. I have corrected paint, but never applied it. I may have to attempt it.

Some of the worst areas...



I have a decent compressor, drier, gun and sanders, polishers and buffers. There are some fantastic videos from Paint Society that make this look doable for someone with limited experience.

 

[SirReal63]

The convertible top was a bargaining chip I used to my advantage. I got the price significantly lower because the rear "glass" was coming out and it was raining when I picked up the car. I researched how to repair the vinyl window and clean the horrid haze off of it. I ended up going with Weldwood Contact Cement after failing with 3M VHB double sided tape and adhesion promoter. The double sided tape failed because the cloth portion was disintegrating, nothing sticks to powder but the powder does come off and stick to the tape rendering it useless. The contact cement allowed adhesion by soaking in to the cloth fiber that was still intact. This method worked beautifully while it was cool outside but one day in the sun and it began to let loose in some areas.

It was always my intention to replace the top, I just wanted to buy some time as there are so many areas that need attention. I could leave the car in the "shop" though it was full of our farming related items, numerous 3-point implements, cement mixer, table saw, welder and accessories, the 97 Suzuki Carry that needs clutch work etc. etc. It took me a week to clean out and organize the shop enough to get the C4 in there and have room to work on it. Many items went outside until I can ***** a shelter for them. I have never done a convertible top before so I researched that.

I am a frugal man at heart, I built our house instead of writing a check, I fix our vehicles when they need it instead of writing a check. We rarely hire anyone to help with the farm chores and infrastructure construction, well, at least until I had my heart attack, now some of that gets "farmed" out to a high school kid. When it came to the top I knew I would be doing it myself, without a clue of how. I hated the thought of putting a vinyl window and top back into this car but learned a glass window version from a newer model could be made to work, they even made a kit for it. Off shopping I went, the kit, no longer available, the actual cloth top much more expensive than the vinyl one and there is very limited C4 specific instructions and tips on doing this job. While browsing FB ScammerPlace for vehicles in the past I knew there was a Corvette specific wrecking yard a couple hours away from me. He actually had a 91 vert on his lot he was parting out. I asked him about the top and it's real condition, but it was about the same as what I had. He did however have a black top off a 95 that was in good physical condition but dirty and faded with the frame still attached. The price was right, more than right. I fired off an email to Mirrock to see if this was as easy as it appeared, they assured me it was a direct bolt on. Now we have a plan, remove the entire frame and top from an 89 and replace it with the entire frame and top from a 95.

The problem...



The solution...as it was before I got it home, really dirty.



I ended up with it for less than asking price which was about a third of the price of just the canvas cloth top. I cleaned this top like a piece of cloth that was dirty, Woolite, OxyClean and a horse brush. I managed to get all of the dirt out of it but it was still faded and stained. I have ordered some Renovo Reviver and Ultraproofer to make it black again. I am keeping my fingers crossed it works. If it does work, then I have the glass window I want, on a frame designed to work with it and mostly my labor as an expense. I went ahead and ordered weatherstrip from Top Flight for the top and Corvette Rubber Latex for the A-pillar. The weatherstrip was bad, on the car and both top.

An interesting thing to me...the top from the 89 appears to be original. The correct screws, placement and length of screws, correct adhesive and the hinges only show one set of witness marks. I don't believe it has ever been replaced. The 95 top by contrast has a mix of hardware, some even correct but most not, 4 different adhesives and the actual fabric is still firm and not worn and looks to have been replaced. I swapped the headliner out of the 89 into the 95 as it was in near perfect condition and the 95 one was tattered.

I do not mind the color change to black, I think it looks better than the Saddle top.

 

[SirReal63]

It took me a week to clean off the old glue, weatherstrip adhesive, contact cement and silicone off the 95 weatherstrip channels. It is done as of today and weatherstrip gets delivered next week. I rust converted the screws and painted them, where the screw holes were wallowed out too big for screws I used black pop rivets, though they will never be seen. I used as much of the correct hardware from the 89 as would fit though many of them had to go back with the incorrect screws I took out.

The agenda for when the top is finished is to figure out a speedometer and hope it is the charred wiring in the console and not the discontinued parts like VSS and plastic gears. I know I will be calling for help when that time comes as though I can handle mechanical things, electrical is not as easy for me. I did get a new shop manual and it will be immeasurably helpful once I learn the layout of it. It does not seem very intuitive at first but I will learn to use it.

 

[SirReal63]

The replacement top is on! Putting it back in the car was about as easy as it gets. I had read it was a difficult task but I found it easy. The weatherstrip were not so easy, they were actually difficult. The rear bow went on like a dream which gave me a false sense of hope when it came to the other 6 pieces. I glued in the rear bow after a test fit and it popped right into place. I did not glue all of the side pieces, I did the risers for the window because they slipped right into place. The two top side did not want to be pushed into place doing the test fit. I wasn't sure I would be able to get them in the channel properly with the adhesive on them. I did manage to force them into place with no adhesive to hold them in, but I do not believe the adhesive would make any difference, these 4 pieces cannot fall out, I am not sure I can take them out without destroying them. The A-Pillar weatherstrip came in today but I am going to wait a little while before putting it on.

The 95 top appears to have shrunk a lot since it was removed from the car it was originally on. I am sure my washing it and letting it dry while not stretched out on a car helped with shrinkage. It took a lot of pulling, tugging and cussing to get the rear pushed down and the top fastened. The hinge plates have a good amount of adjustment so I loosened them up and managed to get the top in place.

I need to find instructions for adjusting the convertible top, and hoping I can find some.

My car is equipped with the proper dash switch and wiring for the rear defroster/side mirrors defrosters but there is an additional harness that I do not have. If anyone knows what it looks like or can snap a pic of theirs, I would appreciate it.

The Renovo should be here this weekend and I will get the top dyed next week. It is actually in good condition, but I cannot get the stains out. I was trying to figure out how to get the canvas to stretch when I remembered we have a really nice Euro-Pro steamer. I steamed the top, in hopes of lightening the stains and loosening the drum tight canvas. It didn't really work on the stains but it appears it did loosen up the canvas.

From 10 feet away you cannot see the stains but the camera really picks them up. It is still wet in these pics and looks worse than it really is...




After drying from several feet away...needs to be dyed.

 

[SirReal63]

I had a perfect day to dye the roof, it rained this morning to settle the dust and then the sun came out and warmed everything right up. I ordered a liter of the Renovo Restorer, thinking I would need all of it, perhaps I will need a second treatment but i only used about a third of the container for the first coat. The first coat really soaked in so if I need subsequent coats it should not take as much.

Getting everything masked off, probably overkill but easy enough to do so why not.



This stuff is amazing...





I will check back when it is dry and determine if a second coat in needed.