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Crankshaft end play

582 Views 4 Replies 3 Participants Last post by  Peter1255
Hello
I am trying to figure out a strange rattling sound in my 3800 and F23 trans combo


Pulled the engine, removed trans. 2 of the flywheel bolts were loose, and the flywheel seems to have slightly touched the bellhousing. HTOB, clutch and everything else seems OK

However, there seems to be play in the crankshaft when I pull back and forth on flywheel (not a loose flywheel). I know there is supposed to be "some" motion, but I cannot find the info on how much play is normal.

Can someone please let me know where I can find this info so I can try to measure it? Perhaps there is too much play, and this is causing my flywheel to touch the bellhousing? Don't know what else could cause this noise.

Thanks
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I just talked to one of my coworkers about this yesterday. When troubleshooting, and you wind up looking at something you're unfamiliar with for the first time, don't hop on the Jump To Conclusions Mat without having a frame of reference for "normal" condition, first. I know you're asking specs, which GM published in the service manuals for 3800 cars, but it's a red herring that will undoubtedly distract you from fixing your noise (sounds like flexplate bolts came loose, which happens on hard shifting setups, and should get Loctite and put back in).
Thanks Dave. The rattlling sound goes away when I depress the clutch. I am trying to get consensus ( as I do not know) whether a bad HTOB would go quiet when the clutch is pressed in. My motor is low mileage, well maintained, so I am more inclined to believe that the issue is in the HTOB/Flywheel
I just talked to one of my coworkers about this yesterday. When troubleshooting, and you wind up looking at something you're unfamiliar with for the first time, don't hop on the Jump To Conclusions Mat without having a frame of reference for "normal" condition, first. I know you're asking specs, which GM published in the service manuals for 3800 cars, but it's a red herring that will undoubtedly distract you from fixing your noise (sounds like flexplate bolts came loose, which happens on hard shifting setups, and should get Loctite and put back in).

Thanks Dave. The rattlling sound goes away when I depress the clutch. I am trying to get consensus ( as I do not know) whether a bad HTOB would go quiet when the clutch is pressed in. My motor is low mileage, well maintained, so I am more inclined to believe that the issue is in the HTOB/Flywheel.

** I should add, found out that 3 of the flywheel bolts were loose- my installed re-used the old bolts which I did not know. So if the issue is a loose flywheel, would that cause the noise to STOP when I press the clutch? There is some rubbing of the flywheel inside the bellhousing, but I don't understand why pressing the clutch would make a loose flywheel noise stop .**
Hello. I pulled the belt off and trying to measure how much crankshaft play I have to try and eliminate the thrust bearing as the potential problem. Could someone tell me if this is a "normal" amount of play?

Thanks

3800 crankshaft play - YouTube
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