• Hello Guest, welcome to the initial stages of our new platform!
    You can find some additional information about where we are in the process of migrating the board and setting up our new software here

    Thank you for being a part of our community!

Catch can, breather hoses and excessive blowby

B20 oil cap with the pipercross style mesh in it and its own baffle not good enough for the likes of TB?

I've never even bothered with the baffle, just B20 oil cap and sharply bent hose and a Y. If you need more than that, time to look for a fresh engine, or, ( if you drive a 7 series in the USA where they are among the top picks for "most worthless cars") another car.

Works to get the average blowby-special B230FT to keep its oil in the pan generally without puking it out of all of the seals or all over the intake with the oil drain tube from the breather box acting more as a fountain than as a drain on most of those by now. Like I said, for most people and those cars, no need to reinvent the wheel. If you need more, replace/rebuild/repair the engine.
 
Buying a B20 oil cap and swapping back to a valve cover without a vent will cost me close to $100 all up, when I factor in the cap, more hoses and fittings, and another valve cover gasket. Ideally I'd like to make my existing setup work if it can.
 
Dauntless said:
Buying a B20 oil cap and swapping back to a valve cover without a vent will cost me close to $100 all up, when I factor in the cap, more hoses and fittings, and another valve cover gasket. Ideally I'd like to make my existing setup work if it can.
Click to expand...

Just add a baffle to what you have, done.
 
Thanks guys. I temporarily removed the top breather hose yesterday as a test. After my 60km daily drive, I got about 30mL from the catch can. Previously I'd get more like 250mL, so I think I've found the problem.
 
Dauntless said:
Thanks guys. I temporarily removed the top breather hose yesterday as a test. After my 60km daily drive, I got about 30mL from the catch can. Previously I'd get more like 250mL, so I think I've found the problem.
Click to expand...

That is no surprise at all to anyone but yourself. Question is, what are you going to do about it?

Did you ever replace to stock breather box, BTW? They do clog over time & cause a restriction.
 
The breather box was replaced about 40,000 miles ago.

I'll run it as is for now. Eventually I'd like to replace the 12mm hose and fittings with 16mm, but they're difficult to find.
 
Dauntless said:
The breather box was replaced about 40,000 miles ago.
Click to expand...

Maybe you need to pull it off and clean it.

blocked.jpg
 
Dauntless said:
The breather box was replaced about 40,000 miles ago.

I'll run it as is for now. Eventually I'd like to replace the 12mm hose and fittings with 16mm, but they're difficult to find.
Click to expand...

Why not just add the baffle as previously discussed? Using larger ID hoses is not a bad idea, but that will NOT alter the oil flow out the cam cover if you reconnect it.

The breather box shouldn't clog unless the oil servicing is left overly long. 100k should be about normal interval for the box, if oil is changed every 3/4k- 3months
 
Hank Scorpio said:
Sounds like you've got it. Btw make sure you have a sealed system with one end tied to the pre-turbo intake still. I've found the vented to atmosphere setups to be worse for these motors than closed systems.
Click to expand...
Thanks Doug. Why do you say that? What specifically did you find?

tryingbe said:
Maybe you need to pull it off and clean it.

http://www.thelostartof.net/tryingbe/bigred/blocked.jpg
Click to expand...
Maybe, but it's had 3000mi oil changes and seems to be functioning.

lookforjoe said:
Why not just add the baffle as previously discussed? Using larger ID hoses is not a bad idea, but that will NOT alter the oil flow out the cam cover if you reconnect it.
Click to expand...
Because I don't live in the US, so a valve cover gasket is $50-60 unless I import one with other parts in a big FCP or IPD order. I didn't want to spend that, plus $50 getting the machine shop to weld in a baffle if I wasn't sure it would help.

I may forget about the valve cover vent, and just run a 16mm hose from the breather box to the catch can.
 
You must log in or register to reply here.
Back
Top