My baby has a leak.

by **mo-is-beta** » 05 Jun 2009 19:40

My tranny (727) has started leaking, its coming from the front inspection plate. I know its probably a seal or leaking converter. does the front seal stop fluid from the tranny or keep the fluid in the converter? anyway I know the tranny will have to come out to fix it. The funny thing is I just replaced the neutral safety switch. is there any other reason for the leak that I should consider before I get crazy and drop the tranny? No the new switch isn't leaking, and No its not overfull (unless the dipstick is wrong)
Thanks in advance, Andy

by **dave-r** » 06 Jun 2009 9:01

It will be the seal around the converter neck and input shaft.

I am replacing that very same seal this morning on mine.

by **Jon** » 06 Jun 2009 14:17

Sounds like a fun job. :disbelief:

That would take me a couple or mornings. :s008:

by **mo-is-beta** » 06 Jun 2009 18:50

so would the leaking fluid be coming from the converter or out of the tranny? The last time I drove it, I had a vibration I never felt before and was wondering if the converter was out of balance because it was leaking. is this a crazy thought, not sure if its even possiable.

by **dave-r** » 06 Jun 2009 20:38

The fluid in the converter and the trans is the same thing. It circulates. You can't loose oil from just one or the other.

The neck of the converter fits into the transmission through a seal. It is this seal that has gone. Because the converter also drives the hydraulic pump in the front of the trans there is a lot of oil in that area.

Don't ever try to remove the trans and leave the converter on the engine. You could damage the converter or pump. Always take the converter out with the trans.

by **dave-r** » 06 Jun 2009 20:41

Jon wrote:Sounds like a fun job. That would take me a couple or mornings.

I dropped the trans out a few days ago. I am installing it tomorrow. Today i was just fitting the new seal and flex plate. :wink:

by **mo-is-beta** » 08 Jun 2009 1:44

wow, thanks for the pics, thats a big help. so drain the converter and trans before I remove it, but do I need to re-fill the converter before I re-install or will it fill itself through the trans. probably another stupid question.
Thanks again, Andy

by **dave-r** » 08 Jun 2009 8:32

Put a pint or two in the converter before re-installing it.

Actually I never bother draining the converter unless the oil needs changing.

Don't forget that the converter is tricky to get back on. It pushes on in two distinct movements. The second one is sometimes a bitch to get lined up. But you can tell the converter is on correctly because the outer edge with the teeth on will be about 1.25 inches back from the front edge of the trans bellhousing. :s017:

by **transman** » 11 Jun 2009 3:10

When you remove the converter, make sure that the hub of the converter is as smooth as a babys' butt. If there is any indication of a grove or marking where the seal rides on the hub, your baby will be leaking again. If there are deep groves in the hub (can come as a result of a bad pump bushing also), you'll need to replace the converter, as the hub is a non replaceable item, unless the converter is cut open. If the converter is cut open, all converter rebuilders I know, rebuild the converter. Under no circumstances purchase a sleeve to place over the hub. :s021:

I've seen them used in the past, a total waste of your time and money. The clearance between the pump bushing and the converter seal is measured in the thousandths.

Good luck.

Transman :s002:

by **mo-is-beta** » 05 Jul 2009 20:56

okay-i've been putting off dropping the trans to change the seal intill after a july 4th car show I like to take my car too. its about a 250 mile round trip. I checked the leak after I got there, and found almost no leak at all, when I got home checked again and know there is no leak at all. am i going crazy? can the seal warm up and re-seal? could it have been over filled with fluid and coming out around the converter somewhere? I'm not complaining and am very happy I didn't drop the trans, but still would like to know whats going on. any ideas??

by **dave-r** » 06 Jul 2009 7:40

There is a vent up above the seal behind the converter. Normally this would be well above the fluid level but it is possible that fluid will come from there if you overfill it or the oil is foaming for some reason.

Leaking Baby.