How hard is it to crack an input pump when installing a 700r4? There isn't any leakage from the tranny but i called a tranny shop and they said to check the pressure in the line and if there isn't any then that is my problem.

I have another 700r4 in our barn are they interchangeable?

 

Though Ill say i am not expert with 700r4s i have to say i have never heard of an pump cracking. Ive heard of pump vanes sheering but the pump itself no. Usually seals blow out (causing a noticeable leak) which would require the pump itself to be rebuilt which isnt the end the world I would guess a shop would charge $250 for something like that. I totally agree with them though that a line pressure test is in order. Would the pump from the other 700r4 interchange? Depends on the year of both 700r4s.

 

Ok thanks for the help...how would i tell what year it is?

 

there's a date stamp on the passenger side of the trans above the transmission pan's rear corner.

 

Cool I'll see what i can do

 

You say "when installing". Does this mean you just put the trans in and now you have no pressure? It is easy to break off the two "teeth" that slip in to the two notches on the convertor. If you dont have them lined up and you try to bolt the trans and motor together they can break off. Ask me how I know I did have to take my trans to a shop to get the input shaft shimmed. This was on my TH350. I'm assuming the 700 is the same. When I put the new pump in, I couldnt turn the input shaft. I also had to make a tool to get the pump out. I couldnt tell you what it looked like or how I made it now though as this was about 5 years ago. I do remember it was simple though.

 

Yes when i was installing it into the car. I'm not sure if it has pressure or not I had to order a pressure gauge to check it. Im going to pull a line on the cooler to make sure its pushing fluid thru the lines.

The input shaft is necked down on the front from a smooth smaller to larger then split up by space between 2 splines. Hard to explain ill see if i can find a photo. I'm guessing if it broke then there would be some noise nor my bell housing would mount tight against the motor.

Thanks

 

Well i pulled the upper tranny line and it didn't push any fluid thru the lines were all dry. This leads me to think bad input pump.

Also If i turn the smaller diameter shaft on the input shaft by hand it turns the shaft at the rear as long as its in gear. When turning the input end i can stop the output end of the shaft from turning. Is this normal? This was all with the tranny pulled. Is this normal?

 

I forgot to add when i turn the tranny by hand it kind of makes a squealing/rubbing sound (not sure where exactly its coming from) but when it was in the car with the engine running it doesn't make any noise.