IntegraR0064

Just want to make sure I'm not missing something. My car is raced and like all s2000s it fills the oil catch can quite quickly if there are any sustained sweepers with throttle input. The catch can is installed in between the PCV and the intake manifold. I want to make draining it as easy and quick as possible.

I have a oil filter sandwich adapter lying around, I was considering putting it on the car, putting a ball valve on one of the ports, then running a line from the catch can drain to the ball valve on the sandwich adapter. I may put another valve on the catch can itself just for redundancy to make sure the valve isn't accidentally opened.

Of course I will only drain the catch can with the engine off, when the engine is on the valve will stay closed. And of course the valve and line will be rated to handle 100 psi and 275 degrees, or more.

Am I missing anything?

My main potential worry is whether there is residual pressure at the oil filter after turning the engine off (which would make draining not work)? Anyone with a gauge have any input on that?

Thanks for any input.

aresk3b

Hi,

When the engine is off, there's no oil pressure. So no residual either.
You can use a braided line...

Or you can empty the catch can in a JDM plastic cup and pour at the engine oil cap.

IntegraR0064

Thanks. What I do currently is drain it into a empty USDM Costco brand water bottle and pour it into the valve cover. If I had a JDM plastic cup maybe that would be better but funds are limited and overnighting plastic cups from Japan is out of my budget.

I have the catch can mounted by the battery though, which is a small space so the bottom of it doesn't have any space under it, so in order to drain it into something I need to take it off which requires having tools on me, plus I need to have something clean to drain into. It's kind of a problem when you're doing it with 5 minutes left to run and your truck is a mile away and I want to minimize how much stuff I need to carry around grid. That's why I'm thinking about this....a solution that doesn't require tools or accessories to drain it.

Good to hear it should work. Yeah I was planning on using high temperature braided PTFE line like this: https://www.pegasusautoracing.com/is...sp?RecID=18636. Should be way overkill .

afzan

The stuff in the catch can is nasty stuff, oil and fuel vapors mixed together IIRC. You don't want that going back into your oil system/motor

IntegraR0064

I appreciate you bringing up this concern but I've thought about it and in my specific case I've decided it's not really a big deal. What happens in a racing environment is it basically just pumps oil through the PCV as oil sloshes up to the PCV valve and it's under vacuum. I agree there's still a little bit of fuel, etc, but it's a very minor part. When I drain the catch can and inspect the oil, I wouldn't be able to tell the difference between that oil and the oil in the pan. I'm draining it multiple times per day.

This is very different than someone who drains their catch can every few months with street driving, in that case I'm sure it's a nasty mixture of stuff.

Plus I change my oil every 2k miles or even more frequently (with Amsoil signature synthetic), so other stuff doesn't really have a chance to build up.

Being honest though one thing I don't like about this is the fact that with the cup method I can take a quick glance at the oil that comes out and make sure it looks decent. This way it's all hidden from me. Definitely a downside but again I think it's worth it to me. Especially since so far the oil always looks fine so not sure why that would change.

aresk3b

LOL at the USDM costco Bottle.

Is the catchcan baffled?

You can also consinder to add an inline oil filter to the return line.

IntegraR0064

Yes, the catchcan is very well baffled. I was using the Saikou Michi but I have this one that I'm going to change to: 42 Draft ultimate catch can


The inline filter idea is brilliant, no idea why I didn't think of that.

aresk3b

I was about to buy the Saikou, but the engine blew...
Vey nice catch can (the ultimate one) maybe a little overpriced.

IntegraR0064

The Saikou works really well, it's just pretty small, only holds a few oz before needing to be emptied, which was obviously a problem for me. Main reason I went to the ultimate one is it's so much bigger. I agree it's really pricey, although I don't think they're making much money on it - the level of machining here is unreal.

CoolGuy094

I used to empty my catch can after each autox event and the amount of gas foamy liquid junk in the catch can would make me weary of ever letting that stuff drain back down into my crankcase.

Just because you are draining more frequently doesn't mean that the bad stuff isn't there. Whether you wait 2 months to drain it or you drain it every day, the same total amount of junk is going to be collected in the can.

Normally that gas liquid crap would be sucked through the intake and burned off. You're talking about putting that junk right into the crankcase. Its not a good idea regardless of the use of the car or oil drain interval.

If you're dying for a quick way to drain the crap out of the catch can, then put a valve on the drain and plumb the outlet of that valve through a hose that is zip-tied off somewhere towards the bottom of the engine bay. When you want to drain, stick a pan under the engine bay and open your drain valve.

Don't drain it into the crankcase.