700R4 leak

[Melitta]

Anyone have information about a 700R4 transmission?   We had the transmission pulled to replace the front seal, put everything back together and now have another leak. Can't see exactly where it is coming from, but seems to be between the flywheel and transmission.  Have had a suggestion that it could be the o-ring on the pump.  Is the pump easy to get too and does it entail taking the pump apart or is the o-ring on the outside of the pump?  Any help would be greatly appreciated!

[tomslik]

yeah, there's a o-ring and gasket BUT you have to pull the trans and then remove the pan and filter, TCC (torque converter clutch) soliniod, bolts around the pump and then, i use a screwdriver, and push the pump out from the inside.

just as well replace the converter bushing too.....

[Dennis the Menace]

Check the area where the dip stick goes in. I had problem with the dip stick tube leakng. I have talked to other people that have had the same problem.
Dennis

[enjenjo]

If the seal was replaced without replacing the convertor bushing, it is probably leaking again.

[Melitta]

OK, at the risk of sounding like a complete idiot.  Where is the convertor bushing?  Is it part of the torque converter?  Is this bushing hard to change or pretty straight forward, just pull the old off and replace?
   
As you can probably tell, this is the first time doing anything more than replacing a back seal.  We don't have access to a tech manual, so while we can do this job, we have never done this before.  Gotta learn somehow, right?

[Crosley.In.AZ]

OK, at the risk of sounding like a complete idiot.  Where is the convertor bushing?  Is it part of the torque converter?  Is this bushing hard to change or pretty straight forward, just pull the old off and replace?
   
As you can probably tell, this is the first time doing anything more than replacing a back seal.  We don't have access to a tech manual, so while we can do this job, we have never done this before.  Gotta learn somehow, right?

it is obvious you do not know what you are doing.  You can make some very expensive mistakes with this 700 pump removing it , trying to replace bushings.

I would suggest finding assistance locally or purchase a repair manual like a ASTG book.  The Haynes type of manuals are useless IMHO.

The bushing of the pump for the converter should be driven out the back side of the pump... Pressed back in using the proper bushing driver tools.

the pump halves must be lined up properly when bolted back together.

As mentioned the pan must come off first to remove the pump... the filter , lock up solenoid must come off.  there may be a transfer tube attached to this pump too.... it must come off also.

[Melitta]

Yes, we do know what we are doing.  We have enough common sense to post on here and ask questions before we get into something we can't get out of.  We are fully aware that we can totally screw this up.  Hence the reason for asking questions on here.  We are trying to get a feel for what we might be getting into.  None of our local auto part stores carry a transmission manual, so instead of just sitting around and waiting for a manual to come through the mail, I thought I would ask on here and see what kind of information I could gather.

We have already pulled the tranny again, checking to make sure that we didn't mess up the spring on the front seal.  This is definitely a trial and error for us, but if we take it to a shop, what will we learn?  Nothing, except being a few hundred dollars lighter in the pocket.  If we totally screw this up, then yes, it will cost us more, but at least we tried.  We have lined up other transportation, so we have to ability to take our time doing this and "hopefully" do it right.

Thanks for everyone help!

[enjenjo]

Changing a convertor bush in the pump is kind of a picky thing to do. It must be done exactly right, or the bushing will move destroying the seal, and damaging the pump. Many transmissions have been destroyed doing this wrong. I would say pull the trans, and have a professional repair it, before reinstalling it yourself.

There are several updates, and fixes that can be done at the same time, that make it less likely to fail again.

[Crosley.In.AZ]

Yes, we do know what we are doing.  We have enough common sense to post on here and ask questions before we get into something we can't get out of.  We are fully aware that we can totally screw this up.  Hence the reason for asking questions on here.  We are trying to get a feel for what we might be getting into.  None of our local auto part stores carry a transmission manual, so instead of just sitting around and waiting for a manual to come through the mail, I thought I would ask on here and see what kind of information I could gather.

My reference was to the job at hand for the transmission repair  work. You are a DIY that has no knowledge of the pump you are about to open up.

When the vanes , rotor and guide rings fall out......... look for pictures to guide you for reassembly.

When you check the side  clearance as you reassemble the pump internal  parts, that clearance is .0015. I would suggest you stake the bushing in place IF the pump is of the early design without a retaining lip machined into the pump bushing area.

I've professionally worked on automatics for decades. Be careful , mistakes are expensive on these modern automatics

Yes,  gather all information you can , good luck.

[Dave]

OK, at the risk of sounding like a complete idiot.  Where is the convertor bushing?  Is it part of the torque converter?  Is this bushing hard to change or pretty straight forward, just pull the old off and replace?
   
As you can probably tell, this is the first time doing anything more than replacing a back seal.  We don't have access to a tech manual, so while we can do this job, we have never done this before.  Gotta learn somehow, right?

it is obvious you do not know what you are doing.  

Yes, we do know what we are doing. We have enough common sense to post on here and ask questions before we get into something we can't get out of. We are fully aware that we can totally screw this up. Hence the reason for asking questions on here. We are trying to get a feel for what we might be getting into. None of our local auto part stores carry a transmission manual, so instead of just sitting around and waiting for a manual to come through the mail, I thought I would ask on here and see what kind of information I could gather.

We have already pulled the tranny again, checking to make sure that we didn't mess up the spring on the front seal. This is definitely a trial and error for us, but if we take it to a shop, what will we learn? Nothing, except being a few hundred dollars lighter in the pocket. If we totally screw this up, then yes, it will cost us more, but at least we tried. We have lined up other transportation, so we have to ability to take our time doing this and "hopefully" do it right.

Thanks for everyone help!

Humm ..
At the risk of sounding like a richard here it seems they have good intentions and a little gentler kinder more helpful answer would make this whole thread look better..

learning is fun but sometimes asking questions really helps to learn..  A simple straight to the point answer without criticism sure helps..
I learned 2 new things last week..
Dave

[Melitta]

Just wanted to say Thanks to all who replied.  We had a suggestion, by a friend, that  maybe we had damaged the front seal by messing up the spring inside of it.  We replaced the seal again, put everything back together and lo and behold....we still have a leak.  We were also able to finally purchase a techbook and get to see some pictures of what all is involved for this transmission.  YIKES!  While I feel we could do this job ourselves with the techbook, the thing is...we still don't know WHAT is leaking.  So, I will take the truck to a transmission shop on Tuesday and let them have a look.  If it involves doing anything that we haven't already done, ie: taking apart the pump...then the shop can have it.  

What we did notice is a very fine mist spraying from around the torque converter.  Hopefully the transmission shop can help find the problem without breaking the bank!

Thanks again everyone!  I will post again once we find out what exactly the problem is.

[Melitta]

I promised I would post what the outcome was on our transmission.  Many of you were dead on in your suggestions.  We had a leak at the pump seal and a hair line crack in the torque converter.  They reconditioned the pump and resealed it, replaced the torque converter and put us all back together.  We are running like new again!  Thanks to all who responded, I really appreciate it!

Melitta

[enjenjo]

We try. We may not always be right, but we are never wrong

[slocrow]

We try. We may not always be right, but we are never wrong

Except for that one time we thought we were wrong,...................but we were really right!