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Topic: Bad pilot bearing? (Read 1416 times) previous topic - next topic

Bad pilot bearing?

Alright, well a few months ago I swapped a t-5 into my car and now I'm having troubles.  Here's the symptoms, tell me if you think this sounds right:
-Tranny chirps like a bearing is bad.  It does it at all times, not just when the clutch is depressed, which makes me believe that it is the pilot bearing and not the throw out bearing.
-When I let off the throttle fast the car jerks a lot.  I've read that since the pilot bearing holds the input shaft, if the bearing is bad it will give some play in the input shaft, causing this.

I've also read that a bad tranny mount could cause too much pressure on a pilot bearing, causing it to "break"/go bad.  I just had a motor mount replaced after doing the swap, so could the twisting from the bad motor mount have caused this to happen?

Bad pilot bearing?

Reply #1 –
did you use some sort of alignment tool?

to me, a pilot bearing has its own sound and you collect a slight vibration that would always be present.  Its a little more violent then just a cherp ,,, unless its just now getting ready to go bad.

Bad pilot bearing?

Reply #2 –
The pilot bearing really does nothing unless the clutch is depressed... With the clutch out the input shaft turns at the same speed as the crankshaft. I had one literally disintergrated on a Turbo Coupe and never knew it was bad, untill I pulled it down to replace a slipping clutch...

If its jerking on decelleration, you have some type driveline problem, maybe the trans itself.

Bad pilot bearing?

Reply #3 –
I went and got it looked at today.  The chirping is some sort of body noise, coming from the shifter possibly?  Not sure, but it's tough to tell.  The jerking is from a bad sensor, I'm thinking maybe the TPS.  I pulled codes 63, 87, and 34.  I already replaced my egr valve and it's sensor, so I know it's not that.  Could a vacuum leak cause these codes?

Bad pilot bearing?

Reply #4 –
Quote from: BIGmeat15071;111347
The jerking is from a bad sensor, I'm thinking maybe the TPS.  I pulled codes 63, 87, and 34.  I already replaced my egr valve and it's sensor, so I know it's not that.  Could a vacuum leak cause these codes?


From Technical Bulletin #89
Ford service codes 1983-1990

34-PFE-- Exhaust backpressure is too high. Check Exhaust system and voltage to ECA.

34-MEM-- Pressure feedback EGR signal out of limits. Check voltage to ECA.

34-RUN-- EGR flow is too low. Check for carbon or obstruction under EGR valve.

63-ALL--Throttle position sensor voltage is too low.

87-ALL--Fuel pump circuit has a problem. Check voltage and amp draw at ECA output.

RUN=KOER
MEM=Continuous codes/KOEO
ALL= Displayed in all test sequences
PFE= Specific to engines with Pressure Feedback Exhaust type sensor.

Not sure about the '88 but most of these cars use the EVP (Egr Valve Position sensor)

Bad pilot bearing?

Reply #5 –
I would suspect the throwout beraing for the chirp if it comming from that area. Is the free play on the pedal set right? If it is too tight, the fork will leave the TO bearing in partial to full contact with the pressure plate diaphram (fingers) which will wear the bearing out very fast. Damage can also be done to the "fingers" as well.
 

Bad pilot bearing?

Reply #6 –
After trying to adjust the TPS that was on the car, I caved and bought a new TPS.  For about a day or two my car was running great, had no problems at all.  When I would let off the gas pedal, my car would continue to drift comfortably like it should.  But now, the problem is coming back.  I changed the TPS out on Sunday.  What would make my car do this?  Should I try bumping the idle up and resetting the TPS?