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-   -   700r4 converter leak (https://67-72chevytrucks.com/vboard/showthread.php?t=388409)

85burb 02-23-2010 01:23 AM

700r4 converter leak
 
Ok so i just replaced my old 700r4 due to a junk reverse and blown out tq coverter seal.. Now my New one is seaping a little..... How much is to much of a leak.. It is not dripping but has collected at the pan seal. What could cause this to happen? It has new coverter too. It is a performance rebuild also if that matters. Dont think this is normal. Any info?

cableguy0 02-23-2010 04:36 AM

Re: 700r4 converter leak
 
The seals leak when the pump bushing is worn out and sloppy or the torque converter hub is torn up. There is no acceptable amount of leakage. Small leaks turn into big leaks and you will destroy the new trans in a matter of minutes if that seal busts loose and dumps the fluid.Did the rebuilder put in a new pump bushing?

bamabaxter 02-23-2010 09:36 AM

Re: 700r4 converter leak
 
I remember reading on the PATC website that when that seal starts leaking or gets blown out, it is due to a bad pump just like cableguy said. If a shop rebuilt it for you, I would take it back to them.

85burb 02-23-2010 11:42 AM

Re: 700r4 converter leak
 
They put in a teflon bushing to handle extra beating is what the site says. I blame it on my old wore out engine that is wearing the seal out. I have only drove it less then 1000 miles. i only get to drive it 2 days a week. My engine does not make the hot oil psi it should any more. I was thinking maybe wore out main bearings or messed up flywheel or something. I beleve the trans people did what they say.

clinebarger 02-23-2010 04:45 PM

Re: 700r4 converter leak
 
Quote:

Originally Posted by 85burb (Post 3819685)
They put in a teflon bushing to handle extra beating is what the site says. I blame it on my old wore out engine that is wearing the seal out. I have only drove it less then 1000 miles. i only get to drive it 2 days a week. My engine does not make the hot oil psi it should any more. I was thinking maybe wore out main bearings or messed up flywheel or something. I beleve the trans people did what they say.


If your main bearing was wiped out you whould hear it. The converter centers on the crank so the flywheel whould not cause this. you put the converter in right? were you careful not the beat the bushing up? Too much pump pressure can cause this. When i build a 700R4 i drill a larger return hole in the pump so the fluid has somewhere to go instead of bypassing the seal, I also Loctite the seal so the fluid can not seep between the pump housing & seal.

85burb 02-23-2010 04:51 PM

Re: 700r4 converter leak
 
Quote:

Originally Posted by clinebarger (Post 3820233)
If your main bearing was wiped out you whould hear it. The converter centers on the crank so the flywheel whould not cause this. you put the converter in right? were you careful not the beat the bushing up? Too much pump pressure can cause this. When i build a 700R4 i drill a larger return hole in the pump so the fluid has somewhere to go instead of bypassing the seal, I also Loctite the seal so the fluid can not seep between the pump housing & seal.

the company that built it put the converter in. they shipped it to me with it in. they said to not remove it if i dont have too. so i didnt.. My motor does make some extra noise. not sure what it is coming from. It has better pump in it than factory. the link is the exact trans i have.

http://racetransmissions.com/store/p...products_id/30

clinebarger 02-23-2010 05:38 PM

Re: 700r4 converter leak
 
Have you contacted them about your problem? I checked out the link, a sales pitch and everything has a catchy name, not saying they cant build a transmission, but the ad doesnt tell me much.

tqlspec 02-23-2010 08:51 PM

Re: 700r4 converter leak
 
Are you certain the leak is from the tranny, and not the engine?

85burb 02-23-2010 11:15 PM

Re: 700r4 converter leak
 
I am certin it is trany fluid. It is coming from behind the converter. i jammed my finger in there and it came out with red fluid on it alittle.

Ya i now know to not buy trans from online places. I could not find a place in town that would do it for neer that price. No i have not told them yet. was hopeing it is trans pan gasket. that is where it is collecting. after i put in lock up harness they sent me and it is still leaking i will call them. but they just going to send me a seal i bet. The seal is only 3 dollers think i can handle that. but theywill be told about it. i has not dripped on to where i park yet. and is not spraying on to my headers yet....

bamabaxter 02-24-2010 08:44 AM

Re: 700r4 converter leak
 
Good luck talking to them. I hope they actually try to help you out.

85burb 02-24-2010 08:53 PM

Re: 700r4 converter leak
 
They have ben helpfull so far. They sent me the right lock-up kit and i did not have to fight with them. we will see.

gchemist 02-24-2010 11:17 PM

Re: 700r4 converter leak
 
There is a brass bushing on the input shaft. You can pull it out and replace it yourself. When the bushing is worn or improperly installed it will leak.

85burb 02-25-2010 12:19 AM

Re: 700r4 converter leak
 
Thanks for the info. They said i think they put a teflon one in for strength. It only has very few miles on it like under 800 i would guess. It did not leak from day one. I will admit i have been giving it a pretty healty beating the last few weeks. But could not give a date i first noticed it. maybe 3 weeks ago. I only drive it two days a week at most for the last 6 months. No long trips at all. I would hate to pull trans out and replace all that stuff and have it leak again in 3 weeks.

Is there any test i can do to see if it is my crank moving too much? My engine does make funny noise like timing chain is hitting the cover or some thing like that. does not really sound like a valve tic... not to say they dont. but it is a different kind of noise. some one told me it is a wrist pin. any ideas??

cableguy0 02-25-2010 08:58 AM

Re: 700r4 converter leak
 
There shouldnt be a teflon bushing there. It should be a brass bushing. If they put the bushing in crooked or marred it up it would wear weird and allow the converter to wobble. Its also possible the seal wasnt fully seated and is leaking. The only way to find out what the problem is would be to yank the tranny out and remove the converter and check everything

85burb 02-25-2010 09:41 PM

Re: 700r4 converter leak
 
Dang it.. not what i wanted to hear.:waah: Dont have a place or time to do that again. thanks for the info.

85burb 03-02-2010 08:31 PM

Re: 700r4 converter leak
 
So i did some work today on my trans. I put new pan on and installed the new lock up harness ans stuff. After i filled and started it a noticed the flywheel moves front to back about 1/8 to a 1/4 inch like it is bent. the converter follows the flywheel in same movement. It looks like the flywheel may be bent a little. If i am not mistaken that would eat the seal out right? maybe slap new wheel on and seal and it will be good?

cableguy0 03-02-2010 08:55 PM

Re: 700r4 converter leak
 
if the flywheel is that bent the bushing in the pump is likely trashed due to being egged out from the wobble. you need to verify if its the flywheel bent or is the crank is actually moving in and out because of a bad thrust bearing.

85burb 03-02-2010 09:58 PM

Re: 700r4 converter leak
 
Ya that is what i was thinking all alone. so i could just pry on the flywheel or the dampener and see if it moves right?

cableguy0 03-03-2010 12:45 PM

Re: 700r4 converter leak
 
I would pry a whole lot. If you grab ahold of the balancer by hand you will likely be able to feel play if there is any. most times when its to the point of being that loose theres not a lot of resistance to moving it in and out. The other check would be to drop the trans and pull the flywheel and just set it on a surface you know is flat or use a straight edge to check it.

85burb 03-03-2010 08:29 PM

Re: 700r4 converter leak
 
I will pull on the balancer and see if i can move it. The guys i work with will tell you i am not allowed to use a pry bar much. I am 6foot 5 and about 300 lbs. They have seen me break alot of stuff. better not try it. thanks for the info will let you know what happens when i go home monday and am close to it.:metal:


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