700r4 Housing leak.

[Loco Mechanic]

What’s up everyone.

I have a 700r4 transmission and after starting the truck (K10 4x4) transmission fluid starts to bubble out of the square part that sticks out from the case. It’s on the driver’s side of the vehicle up above the square electrical harness.
Have any of y’all seen this before? Can I just weld it closed or maybe epoxy it? As far as I can tell it’s not a “high pressure” point so maybe it’s not a big deal? I’ll attach the picture so you can see what I’m talking about.
Thanks in advance for any help and input.

 

[Loco Mechanic]

Here’s the picture

 

[Chevy 88]

I would clean the hole and the area around it with rubbing alcohol, and then coat a screw threads with some Permatex gasket sealer, install the screw with a screwdriver, and then create a thick "patch" over the whole area with the gasket sealer (about the size of a quarter).

 

[Loco Mechanic]

Sounds like a solid idea. Lol



I guess someone along the line put a screw in there to hold some kind of bracket and cracked it?

Like I said before, it shouldn’t be high pressure. It doesn’t start to leak until a minute or so goes by and it’s not a heavy stream of fluid, it just barely bubbles out.

 

[Ricko1966]

Sounds like a solid idea. Lol



I guess someone along the line put a screw in there to hold some kind of bracket and cracked it?

Like I said before, it shouldn’t be high pressure. It doesn’t start to leak until a minute or so goes by and it’s not a heavy stream of fluid, it just barely bubbles out.

It's a control pressure test port. It should have been threaded factory,It is probably 1/8th npt. Problem with npt is it gets 1/8 bigger in diameter per 1 inch of thred,suppose to tighten just over hand tight. It doesnt tighten like a bolt. Its suppose to wedge,to stop leaks.Problem is people don't understand this and try to tighten the fitting tight,it never gets tight,it just cracks breaks or strips. 1st choice ,Id aluminum braze it, cheap and easy with propane and I'd try a 1/8 npt pipe plug screwed in just barely beond snug,with blue locktight after. If you still have a leak ,don't want braze etc.Id still use blue locktight and pipe plug,plus clean everything and cover with JB Weld.Gasket sealer,permatex is not the right sealant,and gasket sealer is not designed to be a patch especially over pressure. I wouldn't hope for the JB weld to be permanent,but it may outlive the the transmission,if not,it is easy enough to occasionaly.

 

[Loco Mechanic]

Ricko,

The test port you’re referring too is towards the front of the transmission case.(I think).The hole in the pic I posted is up above the square electrical connector closer to the rear.
I’ve seen what happens if the “test port” is unplugged…There will fluid EVERYWHERE, EVERYWHERE!!! Lol
One of my friends found out how that happens.

 

[Ricko1966]

Ricko,

The test port you’re referring too is towards the front of the transmission case.(I think).The hole in the pic I posted is up above the square electrical connector closer to the rear.
I’ve seen what happens if the “test port” is unplugged…There will fluid EVERYWHERE, EVERYWHERE!!! Lol
One of my friends found out how that happens.

My bad,I just looked at your pic. I really should have done that first,instead of assuming what was going on. Sorry. Probably shouldn't post after drinking all day either, Budwieser makes Rick dumber.

 

[idahovette]

^^^^^^^UGH, bud makes everybody dumber^^^^^^^^

 

[Loco Mechanic]

I understand that for sure!

It always seems like a good idea to start with. Lol

 

[Matt69olds]

That’s the mounting point cast into the case for the electrical harness. Originally, it had a self tapping screw threaded into it.

Either the hole is drilled deeper than it should be, there is porosity in the case, or someone threaded the wrong screw into the hole and cracked the case. Whatever the cause, it’s no big deal.

Clean the aluminum throughly, mix up some JB weld, fill the hole. If the hole is still needed for the harness, thread in the bolt before the epoxy completely sets up. Problem solved!!

 

[Loco Mechanic]

I was hoping someone would say that. Lol

I’ll get her cleaned up.

Thanks