riderdog

What provides return spring function in this hydraulic system? Is there a spring inside the cylinder, or a valve that "floats" the cylinder when clutch engaged? Reason for asking is that in attempt to lessen noise in Neutral at clutch engaged, I loosened cylinder mount nuts allowing cylinder to back off lessening throwout bearing "drag" pressure. It worked to the point that no further "adjustment" was possible (studs too short). Clutch pedal travel became less to eliminate noise (by about 2/3), while maintaining good shifting. It almost appears that the cylinder "start point" is too far into the clutch disengage cycle that it is not allowing the throwout bearing to unload completely from the clutch diaphram fingers thereby causing "rattley" noise that is common in bearings that are not fully loaded or fully unloaded.
Any helpful comments?

FMB

The Pressure Plate.

Valv

There is no spring inside the cylinder, it's just a piston.
Only spring in the system is the pressure plate. I would re-tighten the cylinder and leave it alone, it's $ 250 for a stock replacement ,

riderdog

Thanks, if PP is providing return pressure (I agree), then it is loading T.O. bearing partially at all times against cylinder residual force causing noise and wear. Also if force to displace T.O. bearing (dirt/dust buildup) is greater than force P.P. can generate (at end of it's travel) it will cause some disc slip and wear (reducing PP spring force).
Valv, mine is tight to OE position, but am thinking of buying second one and modifying rod to be length adjustable and/or installing pullback spring to completely isolate T.O. bearing from diaphram springs at clutch engagement .This will eliminate noise and should reduce self induced wear.

Valv

I replaced my bearings at 211k (truck #7 and 189k (truck # 8), never had a problem, overfill your transmission by 2 quarts and you will have better results than adjusting the cylinder rod