Nipple on Clutch Case, Any Ideas?

[Dustin Matheny]

I picked up a 93 Civic Coupe with a JDM B18C GSR. There is a nipple on the clutch case and I am clueless where it should go. I assume it is a vacuum line, but to where? I have no extra nipples anywhere to connect this too. I took the photo awhile go since then I put a small air filter over the nipple to keep things out. We have run the car with it open and closed and see zero difference in performance. The transmission fluid stays at 185F - 187F during a drive and leaving this nipple open or covering it closed doesn't change the temperature any.

I have tried searching but to no avail. So, I made an account to ask for help. Thanks in advance for any advice you might have. It clearly doesn't seem to be anything important but they wouldn't put a nipple there for no reason. I would like to connect it to its home even if I have to get an adapter.

 

[civteck]

Its a vent that gets a plastic cap to keep water out

Sent from my boujea ass phone

 

[Dustin Matheny]

Thanks for the reply, first chance I had to check this site. So then the simple air filter (breather) I put on should be good enough? This isn't the same product but its close to what I put on https://www.amazon.com/BQLZR-Intake-Crankcase-Breather-Filter/dp/B00RUQNYIM

If that isn't good enough do you have an idea what I should put in its place? I have had quite a few JDM engines (first B18C) but have never run across this nipple. So is this rare or have I been somehow overlooking this nipple on other transmissions? I went to all 3 auto part stores in town but none of them had any kind of cap that could possibly fit it, so the breather will have to work for now.

Thanks again for the reply.