Picking up this car on Sunday. http://desmoines.craigslist.org/cto/1392577716.html

I need opinions on getting this thing to move on it's own, so plan A starts with making the clutch work. Will replacing the slave cylinder cure the clutch problem most likely? Or are there other problems like lines/master cylinders that fail just as often? Hopefully the pressure plate isn't frozen to the flywheel like in one of my other project cars was. That was a pain.

Also, current owner has got it running, but it runs rough. He's done new plugs/wires it looks like from some other pics he sent me. Plans for this part: I want to replace the vacuum hoses that are old or missing for certain, but I also want to remove/replace/repair the fuel system as well. My thoughts are to drain the tank, clean/replace the fuel pump, replace fuel filter, remove/replace/repair all of the O-rings in the fuel distributor and injectors. Is there anything else I'm missing here? Any additions to my plan?

All of this is based on a good compression check and a good turbo inspection. If either don't pass as "good", or if anything pisses me off too bad, then plan B may go into effect. Plan B is an Iron block aluminm head 6.0L Chevy engine sitting in the corner of the garage.

 

Also, the starter only starts the car when you "jump" from terminal to terminal on the starter itself with the key in the "on" position. Is there a starter relay that has gone bad most likely, or do the key switch/boxes typically go bad first?

 

First off, grats on your new ride! It sounds like you have a good game plan, but i would really recommend going to 924board.org and posting there. All the early 924/924 turbo gurus hang out there.

 

Right on, thanks Arominus!

 

des moines craigs list?! your lucky i didnt see that thing where are you located? i dont have experiance with 931s but can turn wrenches.

 

www.924board.org will have all the information you need...much more useful than this site.

 

Nice find, I just posted that one over in the 931 rescue thread on 924board!

1. Register at 924board.org
2. DO NOT start the car again until you replace the timing belt and tensioning roller. It's less than $30 in parts and a relatively easy repair requiring no special tools adequately described in Haynes. If the timing belt strips or the tensioning roller siezes, you will incur thousands of dollars of damage to the head since the 931 has an interference motor.
3. The clutch problem is most likely to be one or both cylinders. Change them both at the same time. They're not expensive, and it's a relatively easy job.
4. The one other major thing to inspect (besides the turbo) before buying is the part number on the exhaust manifold. If it ends in "594" you can pretty much be certain that it's cracked and needs replacing. The ONLY option for replacing is to find a salvaged series 2 unit (part number ending in "596") from another car.
5. Read this thread.

If you have any follow up questions, feel free to post here or send me a PM.

 

You can't weld the cracked manifold?

Could the starter problem be the ignition switch on the back of the ignition assembly?

 

Many have tried. I'm not aware of anyone who has had this approach work. The S1 design is flawed to begin with, which is why they crack. The S2 manifold has reinforcements that make it much less susceptible, so it is really the only viable solution.

The ignition switch probably needs replaced. It is likely that this could be contributing to the rough running conditions as well, if the signal is being intermittently interrupted due to a faulty ignition switch. Common (and cheap and easy) problem to fix. The switch is literally $5 and takes about 30 minutes to replace.

 

I can vouch for that - I replaced the ignition switch on my '84, which should be the same as a 931, in just about an hour and I was working really slowly. And the part was very cheap.

As for the manifolds - that sucks. So an S1 owner has to search around and get lucky and find an S2 being parted out and buy those manifolds? Is there any aftermarket manifold available? It just seems like a really important part with no readily available fix!

 

Welcome to the world of the 931!!! Many parts for these cars are NLA from Porsche, and were never available on the aftermarket. We've been fortunate in recent months to finally bring enough pressure from the global 924 community that we now have things like rod bolts, main bearings, and other basic items being produced in the aftermarket that are NLA.

We haven't been so fortunate with the exhaust manifold. To compound matters, it has a completely unique 3-bolt flange where the turbo attaches, so turbo upgrades require a bit of ingenuity. A lot of this info is covered in great detail over at 924board.org in the 931 Tech section. But yeah, the only option is to find a used uncracked series 2 manifold. I've been known to hoard them.

 

Where are you located? I'm in northwest Iowa.

 

im in pella iowa, used to live in sheldon however. i still have family up in that area

 

Yes, the DSM craigslist. He had it advertised as trade for a motorcycle. I remember seeing it and thinking that it was far enough away that a trade couldn't be made. Then I posted my bike, he contacted me and made an offer I couldn't refuse.

Thanks for the tip about the timing. Another source says the 924 is non-interferance though, unlike the 944. Who's right? Cheap insurance for a car that sat for so long either way.

See below.

Is the manifold a cast design? The trick to welding cast material is to get it cherry red with a torch, then hit it with a MIG/TIG/Arc welder while it's still cherry red. The pre-heating lets the cast material flow out into the weld media. Reinforcing beyond the stock design would keep it from cracking in most cases. And of course it would need to be torqued to spec and "seasoned" to avoid warping and cracking during and after the welding process.

The ignition switch will be bad IF voltage doesn't get to the starter in the "Start" position. If there is voltage in the start position, then it's the starter solenoid/relay. Are the solenoids/relay integral to the starter, or are they external? I know how to troubleshoot the basics, just looking for what happens most on these cars as a starting point.

West Des Moines, IA

Thanks Everyone!!!

 

924 Turbo is interference
924 normally aspirated is non-interference