where is the pilot bushing?

[marckula]

where does the pilot bushing go? any chance it goes around the pilot bearing? that wouldn't make sense but is it possible?? i had my cluthch swapped and they said the pilot bearing 'just fell out' it should be a press fit right?

1995 540i 6sp btw...

[Gearhead]

I've never seen a vehicle use both. It's typically either a pilot bushing OR a pilot bearing. However, if the cage containing the bearing rollers fell out, the outer race of the bearing (looking somewhat like a bushing) would still be in the crankshaft. I'm not sure how BMW worked that part out, and I couldn't find it in the Bentley manual.

What exactly is it you're trying to do?

[yaofeng]

http://i21.photobucket.com/albums/b274/yaofengchen/DSC_1707.jpg

[joshua43214]

The car will have either a bearing or a bushing, cant remember off hand what yours has. the bushing goes in the crankshaft, the bearing goes in the flywheel. Sometimes the bearing will just fall out. They are not a tight press fit, often you can press them in with thumb pressure.

I have seen cars that have both a bushing and a bearing, but I am almost certain no BMW ever did.

[marckula]

I've never seen a vehicle use both. It's typically either a pilot bushing OR a pilot bearing. However, if the cage containing the bearing rollers fell out, the outer race of the bearing (looking somewhat like a bushing) would still be in the crankshaft. I'm not sure how BMW worked that part out, and I couldn't find it in the Bentley manual.

What exactly is it you're trying to do?


this is part of an investigation into the cause of an abnormal amount of vibration. i had the clutch replaced last month and, being a cheap-ass, i only had them resurface the flywheel. i think the flywheel is not balanced anymore so I have a new one for them to install now.

but along with this, I am trying to figure out if theres another problem, this time where the trans input shaft meets the crankshaft via the pilot bearing. when the trans shop pulled the trans to install the new clutch, they said the old pilot bearing was loose and just fell out of the crankshaft. my thought was that the pilot bearing might need to be INSIDE the pilot bushing then press-fit into the crankshaft.

[marckula]

http://i21.photobucket.com/albums/b274/yaofengchen/DSC_1707.jpg

wow thanks for the picture, i can see that the pilot bearing wouldnt fit INSIDE the pilot bushing.

[Bill R.]

You aren't supposed to resurface the dual mass flywheel either.
I don't know if a new flywheel will help or not though. Usually when an engine is balanced you balance the crank,flywheel,pressure plate and the harmonic damper all as one unit bolted together. With appropriate bob weights bolted on each rod throw also. If your getting an abnormal vibration i would inspect the pressure plate itself as well as the clutch disc. Or possibly a bent input shaft from hanging the transmission on it...Any number of possibilities




this is part of an investigation into the cause of an abnormal amount of vibration. i had the clutch replaced last month and, being a cheap-ass, i only had them resurface the flywheel. i think the flywheel is not balanced anymore so I have a new one for them to install now.

but along with this, I am trying to figure out if theres another problem, this time where the trans input shaft meets the crankshaft via the pilot bearing. when the trans shop pulled the trans to install the new clutch, they said the old pilot bearing was loose and just fell out of the crankshaft. my thought was that the pilot bearing might need to be INSIDE the pilot bushing then press-fit into the crankshaft.

[yaofeng]

wow thanks for the picture, i can see that the pilot bearing wouldnt fit INSIDE the pilot bushing.

That's my 525i. Haven't opened up my 540 yet so I don't know if it is the same.