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I've always ran manual transmissions in my Rock crawlers and can install clutches and such with my eyes closed...

I am now building a rig with an automatic transmission (details in signature below...). I have never installed an automatic before, and I was told that I should have a little bit of in and out movement in the torque converter when it is bolted to the flywheel. Is this correct? If so, how much is correct, and how do I measure it?

The mounting bolts that came with the torque converter do not have an unthreaded section next to the head, and they do not bottom out before pulling tight against the flywheel. Do I need a different set of bolts?

Sorry for all of the questions, but I don't want to destroy a custom built $400 torque converter...
 

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with the converter bolted to the flex plate there should not be any movement. it should be tight. but when you install the transmission to the engine there will be a small gap between the converter and the flex plate until you tighten all the bolts. it is a very small gap. hope that helps
 

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with the converter bolted to the flex plate there should not be any movement. it should be tight. but when you install the transmission to the engine there will be a small gap between the converter and the flex plate until you tighten all the bolts. it is a very small gap. hope that helps
Thanks for the reply. So I bolt the converter up tight to the flex plate and use locktite on the threads. Then, when I bolt the transmission to the engine there should be a little space between the torque converter and the transmission. Is this to keep from damaging the input shaft seal, or what?
 

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I've always installed slushboxes with the Torque Converter already on the input shaft, got the trans bolted into place, then bolt the TC to the flexplate. ;)
 

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I've always installed slushboxes with the Torque Converter already on the input shaft, got the trans bolted into place, then bolt the TC to the flexplate. ;)
MUCH MUCH easier way of doing it. Plus, that way you know the pump slots are properly lined up.
 

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Exactly. Your torque converter goes on the input shaft of the trasnmission in a certain way.

Put it on wrong and you torque coverter will not and transmission will suffer do to lack of fluid flow.

MUCH MUCH easier way of doing it. Plus, that way you know the pump slots are properly lined up.
 

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Most of the ones I've worked on you have to push 'em on, turn them, push further, etc. to get all the elements locked on.

Oh, and don't forget to clean all the rust, etc off the flexplate / center hub, especially the cone area in the middle where the TC centers up...
 

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Most of the ones I've worked on you have to push 'em on, turn them, push further, etc. to get all the elements locked on.

Oh, and don't forget to clean all the rust, etc off the flexplate / center hub, especially the cone area in the middle where the TC centers up...
Just for clairification, after the T/Q converter is on the trans ALL the way and the trans bolted to the engine, there should be a gap between the T/Q converter lugs and the flexplate. about 1/6" or so. you should be able to spin the converter with your finger and push it into the crank until the lugs touch the flexplate. this makes sure that the pump gears are not in a bind. now install the bolts. use loc tite and screw `em in till they just touch the flex plate. after they`re all started, then go arround and torque `em to spec. it takes a while ,but it`s not too hard. hope this helps. :beer:
 

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On the snout of the converter,there are two slots cut to engage the pump.You must put the converter(with some trans fluid on snout to protect lip seal) on the input and align as well as possible by sight(so you dont damage the new ft seal you just put in) and rotate the converter while gently pushing it towards the pump.You will feel those slots drop into the pump recess(its a male female slot arrangment unless you building in S.Francisco).Then rotate the converter by hand 360 degrees to be sure the slots found a home.Then after bolting you trans to the motor,you should be able to slide the converter snug against your flexplate relatively easy. Most will let the converter slide forward and back 3/16 s or so.Do not use bolts to pull the converter towards the flexplate,do it by hand.Just rotate slightly back and forth and it should slide right up against you flexplate.If the converter doesnt have those slots properly lined up and seated properly in the pump,it will cause the converter to stick out too far.If this happens,sometimes bolting the motor to the trans will force the not seated converter back and damage the front pump assembly.Also,as noted above,all rust should be removed from crank hub/snout.I was told it could cause the flexplate to crack.
 

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I didn't see this mentioned, but don't forget to add a couple of quarts of trans fluid to the torque converter before putting it on the transmission.
 

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Discussion Starter #11
Thanks Everyone. Y'all saved me from an expensive mistake...
 

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You must make sure the converter is fully engaged, something like three clicks. Clicks= as the hydraulic pump, turbine and stator are engaged.



What they said before as about 1/16" clearance after the housing if fully engaged.

Don't ask me about when the converter is not fully installed and just torque down the bolts the the transmission. :eek: i.e. buy new converter/pump. I started up the engine an it made the most horable wine.... OH shoot!!!
 

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and another leason i have learned in the past put all the bolts in before you tighten them up. it makes it alot easier to get the others in. you will have to thread the bolts in tilll they are almost tight but you can still get movement with the converter if you dont the bolt might get jamed against the block.
 

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torque converter drain

all above is correct. Don't know about 700r4, but some converters have a drain plug, and it has to be aligned with the slot in the flex plate/flywheel to clear. If you don't, you get to replace the front pump and clean the metal out of the transmission like my first install went. I use hi temperature self locking nuts on the converter instead of locktite, available in boxes on order from auto supply but not individually. they have six cuts on the top and are pinched in a little there to hold. Low temperature self locking nuts are cheaper, but have nylon inserts that might melt. If your auto supply doesn't have the dorman or rockwell fastener book, mcmaster.com or fastenal or lawson supply can get the nuts.
 
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