Took the car to Summit Point Main yesterday, driven there many times but first time in this car. First morning session, first hot lap, i notice coming out of 5 (a slow, sharp left through about 110 degrees that follows a heavy braking zone) that there's a bit of smoke out the back. I thought, hm, maybe this is what i have been warned about regarding the need for a catch can on a tracked Mk7? Next lap i get in there a little bit hotter and i leave a small cloud in the same spot... not sure whether the car bogged a little or i just lifted out of surprise at the amount of smoke, but i took it in the paddock and looked under the hood to see if any obvious leakage or hose blown off, etc but nothing of the sort, so back out. This time i warm up a couple laps and when i go in there 9/10 i leave a large cumulus cloud and get black flagged for being a vision hazard.
As i interpreted Hoon's excellent explanation of why a catch can is useful at the track, i figured this was probably the stock oil separator being overwhelmed under heavy braking and then dumping excessive oil into the TIP over a short period of time and while i'm accelerating out of 5. Figured my day was done since i didn't have anything laying around to improvise with, but a guy there offered a piece of hose that i could route the oil separator outlet to a makeshift catch can with. After finally getting that oil separator outlet fitting that satan designed off the TIP, whipped something up with gorilla tape, diet coke bottle, zip ties, and a few blocks of wood to keep this sweet catch bottle in place, lol, and what do you know, it worked for the last few minutes of the second session! Never threw a code either, hm. When i went back in, i also recalled that the right-hander turn 1-2 complex at the end of the front straight does not cause this poor behavior, it's just in that left hander. Seem to recall the Mk6 mill having oil starvation issues but that was with long right handers IIRC? Hm.
Third session, first hot lap, big cloud. Take it back in, check the bottle, the gorilla tape holding the factory fitting to the hose has let go of the hose. There's almost no oil anywhere, though, like one or two drops. Hmmm. I decided that fitting was stupid (it is) and cut it off, then held the little hose in the big hose with a clamp i found. Made sure the little hose wasn't getting crushed and wrapped it with plenty of tape to make sure it wouldn't leak. Went out into the open session, and it starts smoking like a mofo again! Flagger in the next station didn't throw the black flag again, though i could tell she wanted to behind that "you ought park that shit son" look, so i did. DIY CC was still all together and there still wasn't any oil in the bottle, so i hypothesize that the oil separator failed (though i'm not certain of how they fail) and wasn't venting at all... however i'm not sure how this would cause the big cloud if there is no oil being dumped into the intake tract... hmmm... any ideas? TIA.
As i interpreted Hoon's excellent explanation of why a catch can is useful at the track, i figured this was probably the stock oil separator being overwhelmed under heavy braking and then dumping excessive oil into the TIP over a short period of time and while i'm accelerating out of 5. Figured my day was done since i didn't have anything laying around to improvise with, but a guy there offered a piece of hose that i could route the oil separator outlet to a makeshift catch can with. After finally getting that oil separator outlet fitting that satan designed off the TIP, whipped something up with gorilla tape, diet coke bottle, zip ties, and a few blocks of wood to keep this sweet catch bottle in place, lol, and what do you know, it worked for the last few minutes of the second session! Never threw a code either, hm. When i went back in, i also recalled that the right-hander turn 1-2 complex at the end of the front straight does not cause this poor behavior, it's just in that left hander. Seem to recall the Mk6 mill having oil starvation issues but that was with long right handers IIRC? Hm.
Third session, first hot lap, big cloud. Take it back in, check the bottle, the gorilla tape holding the factory fitting to the hose has let go of the hose. There's almost no oil anywhere, though, like one or two drops. Hmmm. I decided that fitting was stupid (it is) and cut it off, then held the little hose in the big hose with a clamp i found. Made sure the little hose wasn't getting crushed and wrapped it with plenty of tape to make sure it wouldn't leak. Went out into the open session, and it starts smoking like a mofo again! Flagger in the next station didn't throw the black flag again, though i could tell she wanted to behind that "you ought park that shit son" look, so i did. DIY CC was still all together and there still wasn't any oil in the bottle, so i hypothesize that the oil separator failed (though i'm not certain of how they fail) and wasn't venting at all... however i'm not sure how this would cause the big cloud if there is no oil being dumped into the intake tract... hmmm... any ideas? TIA.
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