Worn Thrust bearing ............again

[ProPower engines]

It’s not the transmission’s fault when the cooler circuit is restricted by a plugged cooler, a kinked line or a fitting with a restricted orifice that found its way into the car out of the junk drawer in someone’s tool box…..

A common deal is the add-on cooler retained with those zip-ties through the radiator which has slipped down and kinked the rubber hoses which are used to splice it into the system. Or, a chunk of the deteriorated hose has made a flapper or shredded itself into a fitting.

The torque converter slippage is the source of nearly all the heat in the transmission. The source of oil to the cooler is the converter exhaust. If the cooler circuit is restricted the back pressure in the converter makes the area of the stator support a piston in the hydraulic jack which pushes the converter forward. It is just that simple.

In this case the car uses the OEM style cooler in the bottom of the rad. Now this rad was suposed to have been redone by the installer of this engine but I have not got a report from the rad shop yet with respect to the condition of the cooler.
There was no external cooler used on the installation and I bet the rad shop did not replace the cooler if they just replaced or cleaned out the original core.
I will have that info monday morning.

While I did have a talk with the guy that did the trans and installed the engine he swears there is no way the trans can affect the thrust bearing in the engine which I expected to hear from him but his customer is pissed at him anyway and wants an independent inspection to be sure as he was way overcharged for the job

[Kevin Johnson]

Or, a chunk of the deteriorated hose has made a flapper or shredded itself into a fitting.

VERY good point. I think the market is full of counterfeit hose of all types that deteriorates and this goes back many years.

[BrazilianZ28Camaro]

It’s not the transmission’s fault when the cooler circuit is restricted by a plugged cooler, a kinked line or a fitting with a restricted orifice that found its way into the car out of the junk drawer in someone’s tool box…..

A common deal is the add-on cooler retained with those zip-ties through the radiator which has slipped down and kinked the rubber hoses which are used to splice it into the system. Or, a chunk of the deteriorated hose has made a flapper or shredded itself into a fitting.

The torque converter slippage is the source of nearly all the heat in the transmission. The source of oil to the cooler is the converter exhaust. If the cooler circuit is restricted the back pressure in the converter makes the area of the stator support a piston in the hydraulic jack which pushes the converter forward. It is just that simple.

Tuner, do you know the trans lines minimum I.D to flow adequatelly?

I ask because I installed in my car few years ago a trans cooler after the radiator oil cooler and new high pressure hoses. They are rated to 3000psi and the I.D is about 1/4".

All the fittings have this same I.D or bigger. No sharp bends.

Sorry to be slight off topic

[Tuner]

I think ¼” is OK, if it doesn’t get any smaller in a bend or a fitting. I don’t know for sure, but I think most all the OE cooler lines are 5/16” OD tubing or metric equivalent. There are several articles about this thrust bearing problem and the restricted cooler as a cause on commercial engine and transmission rebuilder’s websites. I think we went around this a few years ago on this forum so some searching in here should find some links, otherwise search the web. I think the procedure is to measure the pressure at the cooler outlet from the trans case so as to get an idea of the restriction of the cooler circuit. You might try the transmission section in the YB. http://www.yellowbullet.com/forum/forumdisplay.php?f=30

[BrazilianZ28Camaro]

I think ¼” is OK, if it doesn’t get any smaller in a bend or a fitting. I don’t know for sure, but I think most all the OE cooler lines are 5/16” OD tubing or metric equivalent. There are several articles about this thrust bearing problem and the restricted cooler as a cause on commercial engine and transmission rebuilder’s websites. I think we went around this a few years ago on this forum so some searching in here should find some links, otherwise search the web. I think the procedure is to measure the pressure at the cooler outlet from the trans case so as to get an idea of the restriction of the cooler circuit. You might try the transmission section in the YB. http://www.yellowbullet.com/forum/forumdisplay.php?f=30

Thanks!

[cfm]

I think ¼” is OK, if it doesn’t get any smaller in a bend or a fitting. I don’t know for sure, but I think most all the OE cooler lines are 5/16” OD tubing or metric equivalent.

I replace alot of lines (PS, Brake, Trans, and Fuel) on pickups due to rot. Many OE tranny lines are 3/8" OD. I'd have to find an old fitting to measure min ID.

[toddcalo]

Check to make sure the thrust surface on the crank is 90 degrees from the bearing surface if it is touching at the top first where the oil enters no amount of polishing or fancy oil slots will help. Its nice if you can have a slight angle or clearance ( where the oil enters the thrust surface) to help form a oil wedge Years ago in a circle track car we took two thrust bearings out before catching on to this. Check it with a nice precision square. Good Luck

[user-z68766209]

Dave
Do you know if the the block and tranny have been the same since day one?

[ProPower engines]

The block is the original but the trans I have not got a straight answer from the customer about he can't say for sure.
I think is is but can't positivily comfirm it.
But when testing the trans with the rad used it had 60-80lbs of pressure through the cooler.
The converter fluid is exhausted to the cooler supply and returned to the trans from the other side of the cooler and on both sides there is large amounts of pressure.
Next is to diesect the trans aftsr flow testing the cooler in the rad

Dave

[fdicrasto]

Just a thought. Could the pilot bushing for the stick shift app be causing the convertor from seating properly in the crank. Phil D.

[ProPower engines]

No pilot bushing was left in crank.
At this time we are waiting for the cooler to be replaced in the rad.The restriction was the cooler!

[TMSJoe]

I had an issue with a thrust when the drive shaft was too long. Basically everything was fine until the rear suspension was switched to a ladder bar. When the car was up on jacks the drive shaft looked to have plenty of clearance. When on its wheels the yoke pushed into the tail housing.

[hodge]

I just went through this two months ago if the back of block is parallel that is only part of it. I use a good known standard bell to check dowel location centering the trans.I then gutted the trans then recheck with the auto trans. The engine I was working on was out of parallel by .018" and of center by .014'

[ProPower engines]

The dowel location is good enough that it won't be an issue and the rear belhousing flange was squared to the rear crank
thrust location the 1st time around but the cooler has been the issue all along.

Turns out the rad was done about 10yrs ago and the original cooler was reused and when I cut it in half today the crap still trapped inside was incredible.
An external cooler is going back into the car when the engine is ready again

Dave

[Kevin Johnson]

The dowel location is good enough that it won't be an issue and the rear belhousing flange was squared to the rear crank
thrust location the 1st time around but the cooler has been the issue all along.

Turns out the rad was done about 10yrs ago and the original cooler was reused and when I cut it in half today the crap still trapped inside was incredible.
An external cooler is going back into the car when the engine is ready again

Dave

A picture would be fantastic. Other shops could show it to their customers. I was talking with a local Vette shop owner on Monday and saw a poster put out by a tire manufacturer with all the tread wear patterns. When people are asked to replace something expensive that is hidden away, based on a professional opinion or experience an actual photo of what can happen is worth a lot of hand waving.