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John McM 10-16-2015 05:57 PM

My 964 ownership goes back to 2001, when I bought a '93 Turbo 3.6.

Despite that car's qualities I found my needs changed and bought a C4 for a new found passion, the track. This two year old thread details my initial ownership experience

The C4 saw a lot of track use after that and the Turbo 3.6 languished in the corner of the garage. In the end I decided to sell it. It went to the UK and had a glass out bare metal respray

With the sale proceeds in my hot hands I decided to be very deliberate on my next car choices. I bought a Cayenne for long distance family trips (great decision) and a Cayman R for track duties.

It should have stopped there but I still had to decide on the future of the C4. For a number of reasons still not entirely clear to myself I couldn't bring myself to sell it. I think it's a mixture of being underwater on the investment (full engine rebuilds don't add much value in NZ), the fun I had had with it, a need to 'play' with my cars, and that the R is too perfect.

In the end I sold the R for the same price paid for it, a testament to how sought after those cars are, and rightfully so.

With the C4 my sole sports car, and money in my pocket it was time to give it some love, which it needed.

John McM 10-16-2015 06:09 PM

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A few pics

John McM 10-16-2015 06:15 PM

"Herman the German" was starting to show some gearbox wear. It was becoming almost impossible to shift from 2nd to 3rd gear at higher rpm without graunching gears. I could have shifted slower on the track but it just wasn't in my nature when chasing or being chased.

The plan was to take the car off the road for a few weeks, fix the box, complete a 20,000 km service, fix bonnet dents from the previous owner overfilling the frunk and driver door damage from an over extension somewhere in its past.

Already aware that each dollar spent was 'gone' I didn't intend to 'invest' much e.g. The door and bonnet would be the extent of any new paint.

I posted my intentions on our NZ thread (possibly the biggest thread on Rennlist at 30,000 + posts) and received a fateful call from a fellow Rennlister saying I had well over estimated the cost of a respray and should do the whole car. Thinking of the end result with the Turbo 3.6 I said ok.

John McM 10-16-2015 06:25 PM

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Despite the potential cost of any more amateur hour stuff ups I was determined to do as much on the car as I could. I decided to drop the engine and box in my garage, farm out the gear box repair, then prepare the car as much as I could for the respray. Along the way I would learn how my car works and sort out the items that mechanics see but can't justify sorting out, because we owners don't appreciate big bills.

First up was dropping the engine and gearbox myself. A shop books 5 hours to drop an engine and box, I took a lot longer! First up Is accumulating tools. I already had 4 Esco stands and a couple of low profile jacks! but needed to buy the following to do the job: AC Jack - a fantastic piece of kit. ATV Jack 32mm spanner 36mm spanner Hex sockets

I made a plate to hold the torque tube when the transmission is disconnected and a wooden support for the engine case to fit on top of the ATV Jack. I also made planks to fit under the front wheels, which raise it and allow the rear of the car to be lifted without the front bumper hitting the ground. Before I had even started work I had spent more than a mechanic would charge to drop and refit the engine and box. Goodbye cheap option.

John McM 10-16-2015 06:39 PM

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The instructions to drop the engine and box were in Adrian Streather's book, supplemented by the factory workshop manual. Some steps were easier than others. There were a few moments where I had to look at the steps a few times to get it right.

The biggest obstacle was the driveshaft bolts, where four hex heads were badly mauled. The reason is that the CV rubber joint cover makes it difficult to get the tool squarely in the head. Use a power tool on an angle and you will maul the heads. In the end I had to cut the bolt heads off. I then pulled the assembly apart and unscrewed the bolts with pliers in the gap available. I ordered all new bolts. No mechanic will get their hands on these joints in my ownership.

When working on the driveshaft I noticed that an inner CV joint boot was torn and CV grease leaking. I ordered kits to do four CV joints as I figure one is likely the start.

The only other casualty of the engine drop was a hard clutch line that loops under the transmission. It appears to have seen a few hits in its life and an attempt to make it straight ended up cracking the line. The part took two weeks to source. It doesn't appear on PET with an associated image or part position. In the end I took a punt on a part number with nothing next to it and got lucky.

The actual engine drop was 'relatively' smooth. It helped having some helpers who could think through problems like how to get the rear to 94cm to allow the engine and box to be wheeled out. That's where the AC Jack comes in very handy with its long reach and lifting capacity. Note that when the engine is out of its mount you have few options to lift the body as the lifting points are limited.

John McM 10-16-2015 06:47 PM

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With the engine and box out it was time to separate the two. That was relatively easy. I then made a platform to keep the box upright during its transport to the repairer. Two relatively strong people can lift the box easily. Don't let it tip as oil comes out. Don't ask me how I know.

The repairer opened the box and a list of required parts came back:

2nd, 3rd and 4th synchros.
3rd gear set
3/4th gear guide sleeve.
Complete diff lock assembly

Subsequently I was told that the dog gear on 4th was also stuffed. Oh joy.

I got online and started pricing them up. Wow those items are expensive. I obtained all but the guide sleeve from Rose Passion. They were 2/3rds the price of other suppliers. However they couldn't source the guide sleeve. Neither could anyone else I contacted. It was on back order everywhere from Germany. In the end the mechanic sourced one from scargo (sp) when returning from Rennsport. I also sourced a used one from Cogscogs. Be aware that used guide sleeves should be a matched set.

One piece of good news is that the planetary gear weld was holding up.

John McM 10-16-2015 06:56 PM

With the box on its way to being sorted I turned my attention to the body. My original intention was to do just the door and bonnet but as mentioned above I was easily convinced to do a respray as I had the time to do it right and the car was partially apart from the engine drop so labour costs would be lower.

Be aware that the best respray is a glass out bare metal respray and anything else is a compromise. You just have to decide what level of compromise you will make.

In the end I realised that I could live with a full glass out respray with a gun finish over the existing paint. I had to be convinced over the front and rear glass, but as the windscreen had been replaced recently I knew it wasn't urethaned in (the factory did that with some) and the rear screen is apparently very tough. Long story short I took out the rear quarter Windows and the body guy took out the front and rear screens.

I also took off all lights, both bumpers, dissembled the rear bumper into three pieces, removed the door cards and side sills, and door sill covers. The body guy did the mirrors, door handles, washer nozzles, sunroof and wiper bases.

John McM 10-16-2015 07:28 PM

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Just like Men's health, what you don't know about your body can't hurt you! I hate rust and was reticent to pull windows etc out and find something I didn't want to know about.

In the end we found no rust anywhere apart from the drivers sill, under the cover. Just a couple of spots to deal with and surface rust around the sill inspection plate. All easily dealt with. The hyper extended door took more work but the body guy did a great job.

The rear bumper had a split where the previous owner had hit something, plus there was a melted area at the exhaust outlet area. Off to the plastic repair man who said it needed epoxy and mat as traditional plastic repair wouldn't work on the material.

While working around the door area the body man found a piece of accident damage. It's a 2cm crease where the body tub starts. It appears that the car has hit something low, like a kerb. If that's as bad as it gets after 25 years I will accept that gladly.

John McM 10-16-2015 07:40 PM

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Before the body went, I inspected the carpet. There were two obviously sad pieces 1. The driver sill area where feet had been dragged across it, and my repair of the resultant hole looked bad and 2. The area next to the throttle.

I tracked down a source of the original Sliverknit, bought 3m2 (it is 1.5m wide) and will get those pieces redone. I possibly have enough to do the transmission tunnel and other sill as well, plus the door cards. Apparently a full carpet replacement takes 7m2. This rabbit hole is getting deeper by the day :(

RAASpeedster 10-16-2015 08:09 PM

John Your car looks great. I just received a ducktail for my 1994 C4 Widebody coupe and need to find a grill for it. Do you know what year grill you have on the engine lid? Thanks

Boeing 717 10-16-2015 08:19 PM

Looks like a lot of fun man!!! Keep the pics coming!

John McM 10-16-2015 08:30 PM

Originally Posted by RAASpeedster (Post 12677942)
John Your car looks great. I just received a ducktail for my 1994 C4 Widebody coupe and need to find a grill for it. Do you know what year grill you have on the engine lid? Thanks

You're in luck. I documented it

John McM 10-16-2015 08:54 PM

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Doubling back. Before the car went to the body shop, I tackled the front control arms. At a track day, a mechanic said he thought that they were on their way out. They looked OK, but there would never be a better time to do this. It was labour intensive but I got them sorted. BTW the grease supplied is exactly the same as Copper grease I already had.

John McM 10-17-2015 04:54 AM

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With the body and box being sorted, I moved to the engine. It was fully rebuilt recently so I only intended to do the valve adjust and look at sources of oil leaks.

The engine drop process highlighted that the crank reference sensor plug was melted/fused so I bought a replacement.

The oil leaks look to be coming from each end of the crankcase, the 964 version of a bad curry. I am going to take off the clutch and flywheel then replace the RMS. On the other end I have a leaking nose bearing. I researched options and am going to try the Tom Amon sleeve fix

The valve covers came off for the valve adjust. One of the top ones showed evidence of corrosion. A talented Rennlister has put the dimensions on Solidworks and we will fit his billet design. The lower covers look fine.

When I adjusted the valves I used the Kirk tool. Relatively easy when I got into the rhythm of the process. As I first had to check the crank was at TDC by lifting the distributor caps I had a chance to look at the caps and rotors. They looked well used so I'm replacing them.

I also saw that the rear oil breather pipe was hard and decided it was worth replacing that while access was so easy.

Finally, I have been monitoring a 2cm crack in the face of the alternator fan hub. My mechanic said it was likely coming from the back of the fan so I ordered a replacement.

This is getting expensive :(

John McM 10-17-2015 05:13 AM

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The while you are in there disease is starting to take hold. The engine tin, while fine, is off for powder coating. I'll likely do the intake runners as well. The engine carrier is getting a Rennline reinforcement kit fitted and I'm replacing the transmission mount. I'm also fitting speed bleeders to the diff locks and clutch slave cylinder. Finally, the heat exchanger hoses are being replaced.

With the replacements come the need for specials tools. I pre measured the tension so I can replicate it on reassembly. It was at 35kgs.

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