I'd be listening to Sam.

 

So why would it wear the oil pump side? Not arguing, im trying to figure this out. The machine shop had never seen anything like it.

 

The throw out fork presses against the diaphram which is solidly connected to the flywheel, which is solidly connected to the crank, pushing it (crank) forward against the front (oil pump) thrust face.

I once had a crank worn out in less than 2500k's by a driver who'd bang the clutch to the floor. Had the bearing remetalled for not much $$$ and no problems afterwards once the pedal was pressed with some sympathy. What Sam's advised is also correct. The face is only oiled by splash feed so holding the clutch in especially in traffic jams can also accelerate the wear.

 

Ahhhhh ok its all clear now, I was looking at it the wrong way for some reason. Thanks. Dumb moment on my part, I was too busy looking for a hidden problem I guess

Well, looks like this is from the POs. I dont hold the clutch down for more than 5 seconds give or take, when I know the light is changing. Havent since day one, and im the only one who drives my car except for a few lucky people who got to take it for a quick spin in a parking lot. I also try and always be smooth and gentle on it (I wanted to avoid these kinds of issues )

 

Sent you an email Brian.

 

I know somebody in Calgary, has a 3000ish mile crank, with a bad #2 journal. Needs 25 taken off to be perfect again. I think he's asking a pretty reasonable price. I could pick it up, and ship it greyhound, would be pretty cheap.

All other journals are fine. I don't even know for certain that the #2 rod journal is bad, but he says it's questionable, so I'd start off presuming it's bad, and if it's not, then you got lucky

Let me know if you're interested. It looks like shipping from me to you would be around $40CDN.

 

And, FWIW, the info about the crank is accurate, it's the oil pump side that wears out first, always. Although, I've never seen 1mm of axial play before, that's pretty extreme. Either there was a very stiff pressure plate on there, or some PO liked to hold the clutch in for extended periods of time.

 

Yeah, the oil pump side makes sense now. I was looking at it backwards I guess

When I took the clutch apart, it was all stock parts except for a Cup disc (which became the standard I think). Now the pressure plate thats going on.... Ohhh baby

 

Before getting another crank check out where you could have the thrust bearing remetalled. Have the crank machined, measure the now excessive clearance and work out how much thicker the bearing's thrust face needs to be. Give these specs to the remetaller.
Alternatively, there might even be a non OEM bearing supplier who does oversize, ie beyond factory specs. If so the crank can be machined to suit. This might save you the effort and expense of getting another crank. Years ago I was able to salvage an Alfa crank getting quality, non OEM bearings oversized one grade beyond factory max oversize.

 

You might be able to oversize...

I just noticed that it was Mike B who offered another crank. I didn't even check the name, just saw the avatar and thought it was Skip, lol. I guess we're both just as close. If Mike's doesn't need to be turned, maybe it's a better bet?

I'm pretty paranoid about having a crank built up, I wouldn't be okay with doing that, but that's just my opinion.

Brian, if you're not interested in Mike's crank, I may be...

 

I thought he was Skip too Im a bit paranoid about it too, and the machine shop basically said they generally keep it as a last resort as well. Im keeping him in mind, if I dont buy his ill let you know.

 

I assume remetalled is where they weld it?

They also checked all their supply books and couldnt find another source for bearings asides from Porsche, and Porsche didnt have one big enough to make up the difference. I know they have a second oversize (Paragon or Pelican has it I *think*) and ive heard of a third oversize that you sell your first kid for or something.

Im used to this, dont worry. This is Murpehys Law and How it Affects Brian. I should write a book. Hrmmmm maybe ill name my car Murphey.

 

OK, just went through this with my 87N/A and here is the scoop. The .25 over bearings have the thrust bearing sides (flanges) built-up and assume that the thrust bearing sides on the crank are machined. In effect you have the option of machinig the main bearings (oil journel and also thrust bearing) .25 and using stock .25 bearings. These will not fit unless the sides of the thrust bearing on the crank are also machine. Suggest you buy .25 main bearing set and take the thrust bearing to the machine shop.

 

This seems trivial, but....
If you had 1mm of axial play, shouldn't you need bearings that are at least 0.5mm over? So that the total width of the bearing will take up the extra 1mm? Really, I guess they should be 1.0mm over, since the wear is all on one side?

I could be wrong, it's not a bad idea to try getting an over-size bearing, and taking it in. Perhaps the 25-over bearings are only 25 over on the bearing surface, and are even wider than that.

 

The crank surface where it meets the thrust flange was heavily grooved. To fix that, he figured 10 thou had to be machined off at least. Now to keep it centered, 10 thou would have to come off the other side, making 20 thou or 0.5 mm beyond original specs. That would mean I would need bearings that had that much extra on the thrust flanges. First oversize is 0.25mm, second is 0.5mm. Now thats best case, if more than 10 thou had to be take off, then it would be beyond 0.5mm oversize, I would be looking at third oversize. Thats how he explained it to me, prior to measuring it up.

He and SCAN (shop I go to) put their heads together, and the Porsche bearings do inscrease the flange size for oversize (that was the machinists initial worry, that they didnt do that), but there was too much damage to the crank for simple machining+oversize bearings, and they advised sourcing out a good used one rather than go the welding route. The welding like I said was going to be at least $350CDN. I suppose that means more than 10 thou had to be taken off to fix the grooving (and going by the feel, id say it was a LOT more than 10 thou).