Torque Converter and Transmission Assembly Question - Help Needed

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Kilian

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Hey all, last night I was assembling my rebuilt TH400 with new Torque Converter to the engine and in my first attempt I did not have the torque converter seated completely in the front of the transmission. I didn't realize this until I had attached the transmission bell housing to the back of the engine and couldn't get anything to rotate. Knowing that wasn't correct, I quickly removed the mounting bolts and transmission and discovered that the torque converter could move in just a little further into transmission by turning rear transmission and getting some splines to align.

My question is did I mess anything up by installing things wrong the first time? I know that I had the pump tabs and torque converter slots aligned correctly, and I didn't turn anything in the torque converter/trans because it was too tight for movement, so hopefully what extra pressure was applied didn't mess up torque converter internals. Thanks.
 

Vbb199

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As long as you didnt turn it over, which it seems you didnt , i think it'll be ok.

It puts a mess of pressure on the pump gear doing that, but as long as it didnt rotate, it wont hurt the pump
 

Kilian

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As long as you didnt turn it over, which it seems you didnt
Correct, didn't rotate anything in engine/transmission because of the tightness.
 

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Same transmission
 

Ricko1966

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Okay going back to my first post. My first concern was a cracked pump rotor. Then went back and read you had the tabs engaged. Uncertain if once the tabs are engaged you can create enough pressure to damage the pump. My concern is a cracked rotor breaking in use and filling the transmission with shavings. Hopefully @nickstransmissions will chip in here. I did damage a pump once 20+ years ago,and I didn't turn it over,but I did pull thectransmissiin back out and inspect the pump,yes I caused a crack. It was not a turbo 400 it was some fwd Nissan or Mitsubishi minivan at work.
 
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Kilian

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It seemed like there was a set of splines that hadn't engaged, once I had the engine and transmission separated again, I turned the output shaft of the transmission and then the torque converter slid the last bit into the transmission.
 
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Kilian

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Scared me so bad i took the pump apart to inspect it for damage
Exactly, hate having an oh sh*t moment when putting things together
 

NickTransmissions

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My question is did I mess anything up by installing things wrong the first time?
Not sure where you are with this but if you fill the converter with a quart or two of fluid, install it so it's fully engaged on both sets of splines and the drive gear then start spinning the converter, you will begin to see fluid dribbling out of the supply line fitting on the trans. That tells you the pump is working and everything is mated correctly. Periodically spin it as you move the trans closer to the engine and spin it again once the two have been remarried. If it still feels nice and smooth snd fluid keeps coming from the supply port, you're good.
 

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Not sure where you are with this but if you fill the converter with a quart or two of fluid, install it so it's fully engaged on both sets of splines and the drive gear then start spinning the converter, you will begin to see fluid dribbling out of the supply line fitting on the trans. That tells you the pump is working and everything is mated correctly. Periodically spin it as you move the trans closer to the engine and spin it again once the two have been remarried. If it still feels nice and smooth snd fluid keeps coming from the supply port, you're good.
... had a little trouble with your R&R guys I see huh?

ANY person installing a transmission --- well, let me say this: they are the Numero Uno reason why transmissions fail.

A good R&R Guy is worth a lot of $$$.
 

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