Pilot Bearing - s50 + getrag240

[psyber_0ptix]

OK folks, I have a couple questions as to which Pilot Bearing to use. A lot of people have said if using a getrag240 with m20 flywheel/clutch/pp to use the m20 pilot bearing (12x32x10)

"You use the M20 single mass flywheel, pressure plate, and disk and a euro 323i throw out bearing with a m20 pilot bearing."

http://www.r3vlimited.com/board/showpost.php?p=1996571&postcount=11

"use pilot bearing that was meant for your motor"

http://www.r3vlimited.com/board/showpost.php?p=832781&postcount=4

from what I gather these bearings come in two flavors....

12x32x10 and 15x32x10


Why would you use the pilot bearing that belongs to the motor when the outer diameter and depth is the same. Shouldn't it be matched to the input shaft of the transmission being used?

I don't understand the logic of running say... a 15x32x10 where an input shaft is 12mm when the shaft would never sit contacting the bearing. why have the bearing at all?

That being said, which bearing would I run for the getrag240 for a 91 318i if using an M20 single mass flywheel/clutch/pressure plate mated to an s50?

[blackhawkimpact]

I used a Euro 323i throwout bearing part # 21-51-1-204-525 on my 318is with s50 and m20 setup
edit: thought i read throwout bearing....use the m42 bearing that's what i use since the m20 bearing is too small for the input shaft (m42=15mm hole, m20=12mm hole)

[mega_t2008]

It doesn't matter what kind of clutch are you using... Pilot bearing MUST be in there, and must be matched to input shaft of gearbox... So if you use newer gearbox(M5x,S5x) then inner diameter of the bearing should be 15mm, and if you use older gearbox (M20) then inner diameter should be 12mm...

And, no... You're wrong... Input shaft will be nested in pilot bearing all the time...

[psyber_0ptix]

When talking about the input shaft and pilot bearing....it was more a rhetoric of why have a smaller input shaft hovering concentrically in a larger inner diameter bearing where it wouldn't touch unless some serious deformation were to occur. Not so much that it wouldn't be positioned at the center of the bushing. This is the picture I get of those who are using the wrong pilot bearings for the "motor" application. Obviously the input shaft SHOULD be nested in the pilot bearing. But when is it actually useful the input shaft never contacts?

i'll use the m42/getrag240 pilot bearing (which also happen to be 15mm from 9/1990-on) contrary to previous members' experience. thanks blackhawkimpact for the insight, I have the euro throughout bearing all itching to be installed.

and thanks for the responses clarifying misinformation

[e30s50dan]

I am also installing an S50/g240 and mine measures 12mm. Iam using am20 fly/clutch sport pp Hopefullllly it will be in next weekend

[blackhawkimpact]

I am also installing an S50/g240 and mine measures 12mm. Iam using am20 fly/clutch sport pp Hopefullllly it will be in next weekend

Your pilot bearing is 12mm? Your transmission will not go in/fit.. It has to be 15mm if you're using g240.. ask me how I know.

[e30s50dan]

NO its 12mm for sure!! measured shaft 11.53mm to be exact

[psyber_0ptix]

the plot thickens....

[lifeiskaos]

I'm also using a 12mm pilot bearing with my m52 and g240. Ordered the 15mm by accident and it was way too big.

[psyber_0ptix]

What production date is listed on your 318i's?

mines 02/1991

Both Pelicanparts and RealOEM list 15mm for all post 09/1990

[lifeiskaos]

i dunno, came from a 91 318is so it may be a 1990 build date. I ran into the same issue, which is why I ordered the wrong one. I think realoem and pelican list the part for the e36 m42 which has a different transmission...

[psyber_0ptix]

gottverdammt

[blackhawkimpact]

Maybe thats why mines is 04/91 thats why i used the 15mm

[psyber_0ptix]

ok, I feel better

thanks guys lol