M20 Clutch Life?

[Jimmy Lewis]

My car's clutch is toast. To make a long story short, the shaft between the selector rod and the transmission sheered off leaving me stranded in a movie theater. After much thought, I concluded that driving the car home the short 2 miles in whatever forward gear it got stuck in would be better than having it towed. Turns out the car was stuck in 4th gear, and by the time I barely made the majority of the lights on the way home my cabin reeked burnt clutch. Eric, aka 1991 E30 M42, sold me the part super cheap and I had the car back on the road. It has been a few months now and the clutch is finally slipping beyond what I can stand.

Ok, now the questions. What is acceptable mileage when buying a used M20 clutch and pressure plate? How long do they tend to last when driven reasonably for an E30 driver? I have an offer over on R3V for a flywheel and clutch/pp for $125 shipped. The seller says the clutch has 67,000 miles which seems within reason. I feel that this is a rather stellar deal because I could have my M20 flywheel swap done for roughly $250. I know that I need the 323i TOB, an M20 starter, and some M20 flywheel bolts, but this seems like a good alternative than keeping with the lead weight dual-mass and just purchasing a new clutch. Thanks guys.

[D. Clay]

Mine went 200,000 miles. The car I got my transmission out of had 86,000 miles and had just had the clutch replaced. That's quite a range but it's about as close as you can get. You could check the thickness of the disc. You could also measure a new one. Minimum thickness is 7.5mm for a E30 318is.

[Jimmy Lewis]

Yeah 67K doesn't seem too bad at all. I might have to finalize a deal by the weekend. Anymore input?

[strad]

My M20 cabrio has the original clutch in it as far as I know (I know history back to 70k miles).  Car has 158k miles.  Clutch works just fine.

[m42mccabe]

I would just buy a new clutch and clutch housing. I doubt you need a new flywheel or pressure plate so it should only cost about $200. I'm about to do the same thing myself and that's what I was told.

Go to http://www.bmaparts.com
Here's the part number: BMW051399

[Jimmy Lewis]

But the idea is to have an excuse to swap for the M20 flywheel. I think the deal is too good to pass up and I'm pretty committed.

[AL GReeNeRy]

But the idea is to have an excuse to swap for the M20 flywheel. I think the deal is too good to pass up and I'm pretty committed.

do it.  the m42 will never have enough power stock (even with a chip) to really wear that 6cyl clutch out

[Wise Old Dog]

You are rolling the dice on the used clutch with 67K. How much are you saving with the used clutch? If you have to replace that used clutch in the next couple of years, you'll be cussin your decision.You should lighten and balance the M20 flywheel, and get the shop to machine the mounting surface where the starter ring mounts so it will accept the M42 ring. The ring comes off real easy. That way you wont have to do the starter mod. Performance Unlimited in Norfolk did a good job on mine. How much is a new clutch and PP? All you need is a stock Sachs kit. Spend a little extra now, and you will not have to worry about the clutch for a long time.

[Jimmy Lewis]

Yeah I know it is probably isn't the wisest choice in the end but $125 just seems too cheap. I really don't have a problem with the actual job of dropping the tranny and replacing the clutch, a buddy of mine has a full shop and its the kind of thing that makes us tick. I probably could buy the sachs clutch and pressure plate new and not spend a whole lot more and probably be happier, who knows. You are very convincing, haha. Tell me more about the deal with the starter, if I brought my stuff to the shop you listed would they know where to remove material, because I sure don't.

It's funny because only a few weeks ago I was swaying towards selling my car and buying an M20 car, but this car has a mind of its own, it just makes me happy. I think at the same time as the clutch job I'm going to replace all of my shifter bushings and parts and hopefully get my hands on the tall X5 shift selector. Any other ideas on parts to replace, tranny seals, what else? I think I'm going to keep this car a very long time, long live the M42.

[Jimmy Lewis]

Wow I just realized the sachs clutch and pressure plate without the TOB and other included parts comes out to out around $150 and say I spend $50 shipped on the flywheel; I've got a brand new clutch for only about $75 more. Sounds good to me, thanks for the convincing! I don't know if you are Eric or Eric's dad, but thanks a bunch. When do I get to drive out and get a ride with the rebuilt motor? haha.

[Wise Old Dog]

If you can get the flywheel for $50 shipped, thats a steal. The machine shop caters to a lot of local racers and they have this older machinist there that knows his stuff. They charged me $100 to lighten and balance my flywheel (M40). I figure another $25 to cut the ring gear mount surface. What you have when you're done is the same as a Metric Mechanic flywheel. MM charges $750 for the whole kit including the throw out bearing. Eric just put one on his car with the new engine. Revs up pretty quick. But he hasn't really pushed the engine much. So I don't know how it performs.
Some people recommend to replace the rear main and front tranny seals while you have them exposed. Do replace the pivot pin and inspect the fork for cracks. Don't forget to replace the pilot bearing, there are 2 sizes, depending on your build date. You're really not going to find a much cheaper way to install a nice clutch setup than this. Figure around $400-450 for the works.