crank bearings via oil pan?

[luket]

Has anybody attempted swapping out crank bearings via the oil pan? I've got an rpm dependant rumble in my shifter knob and I'm pretty confident I've got some play in the crank shaft. It would be nice to avoid pulling the engine and this isn't a show car or anything. Any advise would be great.

[kilrwail]

The crankshaft has to come out in order to replace the main bearings. If they're shot, you should be hearing it (and shutting it off!), not just feeling it through the shifter. I would look elsewhere.

[ClarkTheShark]

The crankshaft has to come out in order to replace the main bearings. If they're shot, you should be hearing it (and shutting it off!), not just feeling it through the shifter. I would look elsewhere.

Are you sure? I think it may possible to change them. Not ideal, but possible.

Anyways, I agree with kirwail. main bearings probably aren't your problem. I good way to check it take the oil filter off, cut it open with a pair of tin snips. unfold the filter element and hold it up to the sun, if you see glitter, then your bearings are shot.

[vandor]

I've done that on an Alfa.
However, I doubt that is what your problem is.

[fiatfactory]

.

[kmac33]

Sounds like either the flywheel or clutch pressure plate are slightly out of balance.

[DanD]

Generally speaking, if you had a bad bearing you would have either low oil pressure or a rod through your block. You can inspect your bearings by pulling the pan, but you have to unbolt the pan, lift the engine, and then get in there and unbolt the oil pump. I have done this a few times, and it isn't really fun, but once you get the pan off, it is easy to pull the caps.

I have never seen a rod bearing fail on a Fiat unless the engine ran out of oil or the pump failed. It does happen however. Main bearings rarely, if ever fail unless you run them dry. Did you do a compression check ? Also check your manifold bolts and make sure they aren't loose.

HMM. How about you get a piece of fuel line and use it as a stethoscope to listen to the bearings in the water pump, the alternator and especially the timing belt tensioner bearing. Failing tensioner bearings can be real rumblers, as can the others. Check your clutch adjustment, and make sure your release bearing isn't constantly riding on the pressure plate. That can kill them and could also cause a rumble on the way out.

[racydave]

Check your Guibo and universal joints. It is a bit pricy, but here is a alternate source for the Guibo or flex disc. http://www.spruellmotorsport.com/drive- ... -4655.html

[luket]

i dont think its the drive shaft bearings because the roughness is very dependent on RPM, it instantaneously smooths out when i pass 2200 rpm, with the clutch in, or out, in gear or in neutral, hot or cold. I pulled the valve covers today and found that the lobes on my exhaust cam were a bit scored, while the intake ones were not. I measured the valve lash at .016 on 2-4 and .020 on 1. Also, the sound seems to be a bit louder on that side and theres slightly more vibration on the exhaust valve cover than the intake.
I wonder if ive got a bad cam bearing, or if the slightly tight valve clearances could cause the issue...

[ScotcH]

Check your Guibo and universal joints. It is a bit pricy, but here is a alternate source for the Guibo or flex disc. http://www.spruellmotorsport.com/drive- ... -4655.html

Interesting ... that looks a LOT like a BMW part, but is probably the same for many other European cars.

What are the specs (diameter and bolt center distances) for the FIAT Guibo?