TF727 Torque Converter/ Engine Interface Issue

C

cbmind

Member
Hi there, need some help.. My vehicle is a 1980 IH Scout II traveler with an 82' model 345 v8 out of an IH bus. Recently installed due to issues with former motor (stuck valves). To my knowledge the automatic is original to the Scout, only rebuilt. The engine that came out of the bus was bolted to a 5 spd direct drive transmission. I unbolted my old (at) flywheel, the crank hub spacer, and reinstalled on the 82' bus motor. No problems. The issue comes up that when trying to mate the tranny to the engine, the torque converter mates up to the flywheel, leaving a 3/4" gap between the tranny/ engine bolting interface. I can not get them flush with each other. I separated them, took measurements in several places using a straight edge and engineer's square. I have 1/2" from the bolting surface of the flywheel to the face of the mating surface of the engine. I have 1/4" from the bolting surface of the torque converter to the face of the transmission case. I cannot get the torque converter any farther up inside the transmission case. The final time I removed the torque converter, I notice the transmission input shaft seal rubber was slightly deformed, I couldn't reshape it, so I popped it out, thinking it was preventing full engagement of the torque converter with the input shaft. No difference in measurement, still 1/4". Ideas? Other areas to check? I cleaned out the torque converter, looked down inside the engagement collar, nothing appears to be amiss, same thing with the input shaft of the transmission. I think a new torque converter May be the solution, but don't want to start throwing parts at it. Need help... Thanks guys.

1980 IH Scout traveler w/ 82 IH 345 bus motor (originally Scout 345)
tf 727 believed to be original to truck
Scout d44 front axle
GM c&c 14 bolt rear
Scout Dana 20 transfer case (swapped out d300)
fuel injection
GM disc brake system (8 lug)
Holley distributor w/ GM 8 pin hei module.
 
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Found this by searching... Imagine that. Didn't notice it had alignment tabs, will check when I get off work:)

from scoutboy74:
"the most important, critical, vital, crucial, monumental thing about installing the torque converter, is making sure the alignment slots are properly engaged with the tabs on the pump drive gears, and making double damn sure that the converter is fully seated in the case before you attempt snugging the case to the engine. When you have it in all the way, there will be very little finger space between the back of the converter and the bell shape of the case. Another way to tell is by holding a straight edge across the front machined surface of the case. The converter should be inside the straight edge. Why is converter seating so important? Because you'll either destroy the case while snugging the bolts down...major bummer, or you'll shear the alignment tabs clean off the pump gears the first time you crank the starter...medium bummer. Replacement drive gears are available from several online vendors and are not that big of a deal to replace, but still, you're better off not breaking them. As easy as it is to get this wrong, its damn near as easy to get it right. You just need to mind your p's and q's and take your time. Check yourself before you wreck yourself.

Yes, the rotating assembly should rotate clockwise by hand when the selector is not in park. The one-way clutch will only allow rotation in one direction, hence the name.
 
So how did it go? If you read that thread further, I think you would have come across a measurement I posted from the fsm. There should be a generous half inch gap between the converter mounting surface and the leading edge of the trans case.
 
scoutboy74 said:
so how did it go? If you read that thread further, I think you would have come across a measurement I posted from the fsm. There should be a generous half inch gap between the converter mounting surface and the leading edge of the trans case.
Click to expand...

Yup, worked fine. Glad I found your post, great resource, thanks!
 
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