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Catch Can Filling Up Too Fast When Tracking

ZijinLi

Passed Driver's Ed
Location
Toronto
Car(s)
GTI Mk7.5
Hi all,
I would like to better understand blow-by, pcv and catch-can.
I know that some gas and oil vapours will pass piston ring and escape from combustion chamber to crankcase (aka blow-by), and pcv is designed to release crankcase pressure by re-directing blow-by to intake. And catch can is designed to catch the dirty stuff out of pcv so it does not go into the intake.
My car has the spulen v2 catch can. Under normal street driving, the catch can fills up pretty slow (about 50ml for 60km driving). And if I drain the catch can, the stuff coming out are light yellow and gooey. I assume this is normal amount of blow-by that got released from pcv.
But when I go to the track, the catch can fills up super fast. Last track day I drained about a quarter in total (I did about 50 laps of a 3km track). And the stuff coming out are dark, almost black, and not as gooey are the drain from street driving.

My questions are, what is the stuff coming out of the pcv when tracking? Is it blow-by or is it just engine oil? And why there are so much of it? Is it because when corning at high G, engine oil is shaken to the top and get sucked by pcv?

Appreciate if someone who understands this can give me an explanation.
Thank you!
 
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jimlloyd40

Autocross Champion
Location
Phoenix
Car(s)
2018 SE DSG
There's several guys experiencing this and I've yet to see a solution. Are you absolutely sure it's plumbed properly? Have you asked Spulen?
 

ZijinLi

Passed Driver's Ed
Location
Toronto
Car(s)
GTI Mk7.5
There's several guys experiencing this and I've yet to see a solution. Are you absolutely sure it's plumbed properly? Have you asked Spulen?

Hi, I'm not quite sure what do you mean by "plumbed"?
When I go to the track, I ran 7-10 lap sessions, and I drain the catch can and top up engine oil after each session.

Also, how can I contact Spulen?😂
 

jimlloyd40

Autocross Champion
Location
Phoenix
Car(s)
2018 SE DSG
Hi, I'm not quite sure what do you mean by "plumbed"?
When I go to the track, I ran 7-10 lap sessions, and I drain the catch can and top up engine oil after each session.

Also, how can I contact Spulen?😂

I mean the plumbing of the hoses so that they are connected to the correct place.

To contact Spulen go here and use the contact form.

http://www.spulengineering.com/
 

ZijinLi

Passed Driver's Ed
Location
Toronto
Car(s)
GTI Mk7.5
I mean the plumbing of the hoses so that they are connected to the correct place.

To contact Spulen go here and use the contact form.

http://www.spulengineering.com/
Thanks!

The install was done by a trusted mechanic so I'm quite sure it was done correctly. Besides it's just one hose from PCV to catch can, and anther hose from catch can to intake, not much to go wrong here.
My local performance shop says a baffled oil pan would help but I'm skeptical. That's why I'm trying to understand where all the oil are coming from when tracking.

I asked Spulen and if they reply anything useful to me I will post it here.
 

jimlloyd40

Autocross Champion
Location
Phoenix
Car(s)
2018 SE DSG
Thanks!

The install was done by a trusted mechanic so I'm quite sure it was done correctly. Besides it's just one hose from PCV to catch can, and anther hose from catch can to intake, not much to go wrong here.
My local performance shop says a baffled oil pan would help but I'm skeptical. That's why I'm trying to understand where all the oil are coming from when tracking.

I asked Spulen and if they reply anything useful to me I will post it here.

Yes please do post what you find out because there's several other guys experiencing the same thing when they race their car. One guy gave up and parted out his car because of this problem and is moving to a different brand of car.
 

JerseyDrew77

Autocross Champion
Location
Virginia & NC
Car(s)
2016 TR GTI S 6MT
I know I had to get my Spulen PCV plate replaced due to a faulty o-ring. It was slowly leaking out oil from the top and I believe there were a few other members that had the same issue. I think Quebster had the same o-ring issue with his. Not sure if that could cause the catch can to overfill.
 

aaronc7

Autocross Champion
Location
Clovis, NM
Yeah, it's probably straight up oil. The head fills with oil from lots of high rpm driving, high G scenarios. Then you get back into the power, there is some blowby pressure, that pressure has escape the head/crankcase, so out it goes into catch can, taking engine oil with it.

Baffles and PCV plate design help, but can only do so much.
 

Lord_Flexington

Go Kart Champion
Location
Syracuse
Car(s)
15 MK7 GTI LP PP
Hi all,
I would like to better understand blow-by, pcv and catch-can.
I know that some gas and oil vapours will pass piston ring and escape from combustion chamber to crankcase (aka blow-by), and pcv is designed to release crankcase pressure by re-directing blow-by to intake. And catch can is designed to catch the dirty stuff out of pcv so it does not go into the intake.
My car has the spulen v2 catch can. Under normal street driving, the catch can fills up pretty slow (about 50ml for 60km driving). And if I drain the catch can, the stuff coming out are light yellow and gooey. I assume this is normal amount of blow-by that got released from pcv.
But when I go to the track, the catch can fills up super fast. Last track day I drained about a quarter in total (I did about 50 laps of a 3km track). And the stuff coming out are dark, almost black, and not as gooey are the drain from street driving.

My questions are, what is the stuff coming out of the pcv when tracking? Is it blow-by or is it just engine oil? And why there are so much of it? Is it because when corning at high G, engine oil is shaken to the top and get sucked by pcv?

Appreciate if someone who understands this can give me an explanation.
Thank you!
Hey I'll try n shed some light.

What you are experiencing is actually pretty normal.

Normal street driving its fine, but under track it gets heavy. That is actual flowed oil being collected. I have been told that if I had to I could reuse it. I just so happen to always bring some extra oil with me for track days just in case.

What we do is empty every 2 sessions (15-20minutes per session) Into a bottle to see whats going on.
The unit is doing its job its just our cars really do collect that much under pressure.

Temperature does play a factor as does oil type.

Using Mobil 1I would be dumping every session with an almost full can.

Castrol was a bit better but not by much.

Liqui Moly 5w-40 with Mos2 additive does the best for sure. At the end of a 3 day time attack event we just under a 26 OZ
The mos2 does a really good job with its wizardry, i see your in Toronto I can reach out to the LM rep there and see if he can get a sample sent your way. (I race up in Canada too!)


https://www.amazon.com/gp/product/B07THD2BYT/ref=ppx_yo_dt_b_asin_title_o08_s00?ie=UTF8&psc=1

I use that to collect the drain.

Oil temps were down as well which leads me to believe there may be a correlation with Oil types and performance.

When did you purchase your can? I can get you in contact with them to see if they have any updates. My v1 was certainly not as good as the v2 version I currently have.

I hope this is helpful and thanks for sharing your input! Need more Mk7 on track!
 
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ZijinLi

Passed Driver's Ed
Location
Toronto
Car(s)
GTI Mk7.5
I got reply from USP:

"It sounds like the catch can is operating normally. You are correct, when tracking the car and cornering the with higher G forces allow some oil up into the top of the engine. When daily driving your car the catch can pretty much only catches sludge from the blow by. I do not have the exact volume size of the can unfortunately."

If this is true I think a baffled oil pan would indeed help prevent oil from shaken to top, thus make the catch can fill up slower.
 

Gvazquez

Go Kart Champion
Location
North Carolina
I got reply from USP:

"It sounds like the catch can is operating normally. You are correct, when tracking the car and cornering the with higher G forces allow some oil up into the top of the engine. When daily driving your car the catch can pretty much only catches sludge from the blow by. I do not have the exact volume size of the can unfortunately."

If this is true I think a baffled oil pan would indeed help prevent oil from shaken to top, thus make the catch can fill up slower.
I've recently heard that a baffled oil pan does not help with this either. Sounds like theres no remedy for this issue here besides just keep emptying it and stopping off oil
 
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