15 replies to this topic

[RHDmini74]

So I recently started this new rebuilt motor. Kept idle up around 2500-3000 to break in bearings. I pressed in the clutch to go into first to pull the car back into the garage. When I pressed the clutch the car didn't want to go into gear and the idle dropped and killed the car. I know this could be thrust washer issues. I checked the clutch adjustment and everything seemed okay. I tried again and same thing. Yesterday I took the clutch and flywheel out to see if everything looks okay and it did. I changed the clutch and backing plate to another new one I had and put it all back together. Started the car and the car still didn't want to go into gear, and the idle dropped when i went to press the clutch in again. So i turned off the car. Im ready to pull the motor and tear it down to check it out. I found it weird that the car didn't want to go into gear with the clutch pressed down. Is there something else I should check before I pull it out and tear it down? Or would the bad thrust washers not make it go into gear also? I also pressed the crank pulley with a pry bar and there was no movement in or out, i read that thats a way to check if the thrust washers are wrong. Thanks!

[nicklouse]

who build the engine?

 

if the thrust float was measured and the correct ones fitted it should not be an issue.

[Bat]

Hi,

Have you adjusted the two big nuts in the middle of the clutch cover (wok) to stop the clutch traveling too far?

Cheers 

[RHDmini74]

who build the engine?

 

if the thrust float was measured and the correct ones fitted it should not be an issue.

Me and someone else about 8 years ago. I honestly can't remember. The engine was sitting for about 30 years prior before we rebuilt it

[RHDmini74]

Hi,

Have you adjusted the two big nuts in the middle of the clutch cover (wok) to stop the clutch traveling too far?

Cheers 

Its a pre verto. I have it adjusted with the set screw in the wok and the two big nuts

[Bat]

Hi,

Try screwing the big nuts in another turn just to see if it makes a difference?

Cheers 

[Retroman]

Sounds like a centre main bearing issue,

 

Can you measure the end float on the crank ?

 

Could also be the primary gear binding on the crank...Could the primary gear be new or have had new bushes fitted ?

[RHDmini74]

I would have to take the engine apart to measure the end float though right? Also the primary gear spun freely around when I had the clutch apart yesterday.

Sounds like a centre main bearing issue,
 
Can you measure the end float on the crank ?
 
Could also be the primary gear binding on the crank...Could the primary gear be new or have had new bushes fitted ?

[nicklouse]

you could do it with the engine still in the car. measuring the movement on the crack pulley end.

[RHDmini74]

Where would I put the feeler gauge? Do I use a pry bar or should it move by hand?

you could do it with the engine still in the car. measuring the movement on the crack pulley end.

[Spider]

Where would I put the feeler gauge? Do I use a pry bar or should it move by hand?

you could do it with the engine still in the car. measuring the movement on the crack pulley end.

 

 

You'd insert a Dial Gauge in to the Timing Hole and land it on the Flywheel, then with a suitable bar, lever the crank from the Damper end, however, be careful not to damage the Damper.

 

Or, you could remove the starter motor and lever from there, however, be sure what you're measuring is crank float and not flex in the flywheel if doing it this way.

[Rorf]

I think you are going to find that your clutch has been set up incorrectly - too much force required to have it disengage which then puts that force onto the crankshaft which then damages the crank thrust bearings.

 

Did you skim the pressure plate and clutch friction faces, is the ear height of the pressure plate correct, are the 3 clutch straps parallel to the flywheel etc/

 

And what clutch plate do you have.

[RHDmini74]

I think you are going to find that your clutch has been set up incorrectly - too much force required to have it disengage which then puts that force onto the crankshaft which then damages the crank thrust bearings.

 

Did you skim the pressure plate and clutch friction faces, is the ear height of the pressure plate correct, are the 3 clutch straps parallel to the flywheel etc/

 

And what clutch plate do you have.

I tried two different new clutches. one was borg warner. The other I'm not sure. Also tried two pressure plates. same thing happened. One of the clutches and pressure plate was in my old motor which were working fine. only had 100 miles on it in the other motor before I pulled it out.

[Retroman]

I would have to take the engine apart to measure the end float though right? Also the primary gear spun freely around when I had the clutch apart yesterday.
 

Sounds like a centre main bearing issue,
 
Can you measure the end float on the crank ?
 
Could also be the primary gear binding on the crank...Could the primary gear be new or have had new bushes fitted ?

 

   Soz meant to say you need to use a dial gauge as per how Spider and Nicklouse suggest...

 

There is nowhere to measure it with a feeler in-car

 

If its 0.003 to 0.006" you can say it should be OK and look for something else.

[Sprocket]

I’ve hear this happen when the thrust bearings were installed with the bronze face towards the block. The crank just grabs the plain steal back of the thrust bearing and the idle speed drops off significantly if not stall the engine.

The shape of the thrust bearing bronze face allows the oil escaping the main bearing to pass between the thrust bearing and the crankshaft were oil gets drawn in by hydrodynamic action onto the thrust bearing face. With the plain steel side towards the crank, oil still escapes the main bearing but does not lubricate the thrust faces anywhere near enough to stop metal to metal contact under the thrust load of clutch disengagement.

Please note, this is only one possibility.

I’d agree that if the pre verto clutch has not been properly set up it can cause excessive thrust loading.