noise from flywheel housing?

[scatterling]

Ok so I'm stumped.
The long version - I rebuilt the truck, had it inspected and have driven it about 60 miles.

There is a klacking noise coming from the flywheel housing. It only makes the noise under load and it makes it regardless of whether the gearbox is engaged or not. If I go down the road and coast with everything in neutral there is little to no sound. If I hit the gas it klacks loudly and then fades as the revs go down. I have been under the truck with a stethascope - not engine noise or gearbox noise.

Took the gearbox out and saw that the split washers for the bolts holding the clutch cover to the flywheel had opened up and were no longer round but the clutch cover was not loose. There are no score, rub marks or shavings in the bellhousing.

I know I should have, but I never checked the runout on the flywheel after having it resurfaced. Checked it this morning and it is 0 - .006" out. Bible says it should not exceed .002" ( not knowing anything about such tight tolerances I'm not sure if that is creating the problem)

Also I noticed slight scoring on the bronze bush in the center of the flywheel.

So Monday I am going to take the flywheel to get re-surfaced as well as get a new center bush.

My question to all guru's is: am I possibly on the right track?

Has anyone else experienced any similar klacking?

[Terrys]

six thous is alot of runout. That will definately lead to failure of the pilot busing, wear to the friction plate and input shaft slines.
Check your pressure plate for broken springs.
If you're going to have the flywheel refaced, have it blanchard ground, not turned.

[jac04]

.006" is too much runout. I don't know if it would cause noise, but I suppose it could cause noise at the interface between the clutch fingers and the throwout bearing.