Manual Transmission Vent

[catimann]

Checked the forum and my Bentley manual but can't find a description on how to re and re the transmission vent.
I assume it has an O ring and just slides in or out but just when you think you have it figured and engineer steps up to the plate. Nice guys but they designed our differential mounts and body. Thus we needed Randy.
No. 15

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[Randy Forbes]

Why do you want to take the vent out? If it was sealed, per se', it wouldn't be much of a vent!

That's it, on the top of the xmsn case (right-center)



I did have a need to seal a vent temporarily once, while to a smoke-generator to detect leaks.



Factory remanufactured exchange unit__it's like they didn't tighten any of the bolts!

[catimann]

I don't want to "remove it" but remove and replace it ("re and re") with a new one. Unless it can be tested to function. I suppose i could blow air (low pressure) into the fill hole, now that you pointed out the test you used.

[Vintage42]

What might be the symptoms of a plugged transmission vent?

[Randy Forbes]

What might be the symptoms of a plugged transmission vent?

Excessive oil being pushed out the shaft seals, though historically, it's much more common with differentials than xmsns (neither seem to be much of a threat to our cars though).

[catimann]

Um how is this vent installed? Am I right to assume it just pushes in?

[rf900rkw]

Pressed in is a better description. You are obsessing on something that simply does not fail.

[djb2]

My experience is with e30 transmissions. There it is a plastic cap over a steel sleeve forming an imperfect one way valve. Unlike a pinhole vent, it's very unlikely to clog. Any pressure build-up lifts the cap a bit, clearing any forming clog. The shape and location keeps out water for anything short of long-term immersion.

It's difficult to see how it could go bad, except by crushing it when the transmission is out of the car.

[rf900rkw]

That is the getrag vent. The ZF vent is a piece of pipe that has the outer end closed off and a small hole drilled at 90 degrees.

[catimann]

Back at it again finally. This vent looks like the one in the picture Randy provided. (based on the tiny mirror view I can manage to see with.)
My question: Is the vent nothing more than a hole into the trans? If it has a one way type of valve function then I will have to replace mine as the smoke test tells me it is plugged.
To expand on this and give further details as to what I have done and found out. I took my shop vac and attached a hose which I molded to the shape of a 8mm socket (same dia as the vent) Gave it some suction. Then I made smoke generator.
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This works well (got the idea from Utube and it uses a sock and mineral oil with a soldering iron) but it is not really necessary. To have absolute proof that even slight pressure would work I fully covered the vent with some baking soda. Then used the hose through the fill plug and gave it a large puff of air with my mouth. I watched with a mirror as the baking soda blew out of the way. Vent open.
To access the vent, located on top of the trans) You need to drop down the back end. So disconnect the drive shaft, exhaust just after the cat. and the cross member that holds the rear of the trans.

All that said I still have a leak. That will be for another post once I get to the bottom of it.