I know they make off set dowl pins to correctly locate the transmission imput shaft with the crank. How would this be checked to see if the input shaft and crank line up correctly. I have the motor and trans out of the car.
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Mark,
I posted this very same question in long form in the ZF forum, here is the link ZF thread. I never did get a response. I too would like to know how the shade tree mechanic can accurately make this calculation. When the day comes when I need to do this, if it comes down to it, I'll take the short block assembly and the ZF down to my place of employment and set them up on a surface plate, establish a centerline plane through the output shaft and crank and do the math. I have this terrible feeling that this is an item that has been over looked in many Cleveland rebuilds and could be the culprit in promoting bottom end failures and wear.
So Mark, after you have read the thread I linked to above, does making sure alignment correct seem as critical to you as it does to me?
Ron
I posted this very same question in long form in the ZF forum, here is the link ZF thread. I never did get a response. I too would like to know how the shade tree mechanic can accurately make this calculation. When the day comes when I need to do this, if it comes down to it, I'll take the short block assembly and the ZF down to my place of employment and set them up on a surface plate, establish a centerline plane through the output shaft and crank and do the math. I have this terrible feeling that this is an item that has been over looked in many Cleveland rebuilds and could be the culprit in promoting bottom end failures and wear.
So Mark, after you have read the thread I linked to above, does making sure alignment correct seem as critical to you as it does to me?
Ron
I have read that it becomes more important with increased horsepower on drag type cars. With the sometimes sloppy factory specs and blocks that have been line bore seems to be a valid concern for both the long term life of the trans and engine.
Mark,
you wrote the magic words, align boring. Thats why off set dowels are manufactured, as well as "short" camshaft timing sets. They correct for the same problem, at different ends of the crankshaft.
With the flywheel & clutch removed, the trans pilot shaft should slip into the pilot bushing in the end of the crank witout binding or bending.
If after align boring the crankshaft journals you determine a "short" timing chain set is required, then you should expect to compensate the other end of the crank as well. If you run a standard timing set, you shouldn't need to use off set dowels, unless ZF or Ford screwed up their machining to begin with. If that was the case, you would have been experiencing clutch engagement/disengagement problems or the tranny input shaft bearing would have failed prematurely. Make sense?
With the crankshaft installed into the bare short block with main bearings installed & main caps torqued down, and the pilot bushing mounted in the end of the crank, the crank should not require any additional force to turn with the tranny & bellhousing installed than without (sans flywheel & clutch). If so, then the pilot shaft is obviously binding in the pilot bushing due to mis-alignment.
That's how this mechanic would empiracally verify the alignment of crankshaft & pilot shaft.
since you mentioned high horsepower drag racing, I'll mention that I would expect this alignment is much more critical in the world of high rpm racing, just as every other dimension is equally more critical. But that shouldn't apply to you & your Pantera.
Of course, we talked about that at the PI BBQ, you like going fast! lol ...
your friend on the DTBB, George
you wrote the magic words, align boring. Thats why off set dowels are manufactured, as well as "short" camshaft timing sets. They correct for the same problem, at different ends of the crankshaft.
With the flywheel & clutch removed, the trans pilot shaft should slip into the pilot bushing in the end of the crank witout binding or bending.
If after align boring the crankshaft journals you determine a "short" timing chain set is required, then you should expect to compensate the other end of the crank as well. If you run a standard timing set, you shouldn't need to use off set dowels, unless ZF or Ford screwed up their machining to begin with. If that was the case, you would have been experiencing clutch engagement/disengagement problems or the tranny input shaft bearing would have failed prematurely. Make sense?
With the crankshaft installed into the bare short block with main bearings installed & main caps torqued down, and the pilot bushing mounted in the end of the crank, the crank should not require any additional force to turn with the tranny & bellhousing installed than without (sans flywheel & clutch). If so, then the pilot shaft is obviously binding in the pilot bushing due to mis-alignment.
That's how this mechanic would empiracally verify the alignment of crankshaft & pilot shaft.
since you mentioned high horsepower drag racing, I'll mention that I would expect this alignment is much more critical in the world of high rpm racing, just as every other dimension is equally more critical. But that shouldn't apply to you & your Pantera.
Of course, we talked about that at the PI BBQ, you like going fast! lol ...
your friend on the DTBB, George