EICSB100 – SBU Pressure Plate Problem

Application

U1300L Camper – Also applicable to most SBU models

Problem

Severe vibration between 1100-2300 RPM’s

Cause

Worn Pins on the pressure plate allowed the clamping surface (plate) to shift in the housing. At higher RPM’s the plate would center itself and the vibration would go away.

Detail

This one had us stumped. Engine oil clean as can be. Injectors/fuel system working properly. Harmonic balancer in perfect condition. Next step was removal of the bell housing/pressure plate assembly. Even with these items removed, all looked good. Clutch disc had minimal wear. Pressure plate looked good. Upon examining the pressure plate we noticed that we could shift the plate with a screw driver. The first 2 pictures show this movement. Once we found the movement, the pins were the obvious culprit. Had we just visually inspected the pressure plate we would not have found the problem. It actually required us to pry the plate over with a screw driver.
It makes sense that at lower RPM’s the plate would stay off center, causing the bad vibration. Due to the centrifugal force as the RPM’s increased the plate centered itself, hence the vibration went away at higher speeds.

Notice how close the pressure disc is to the housing.

 
Compare to the above picture – obvious how far out of round.

The culprit – Warn pins. Their should be NO STEP on Pins.

 
All 4 Pins had varying degrees of wear.