I'm planning to redo this with a completely different setup over the winter, but since I'm sitting here with nothing to do at the moment I figured I'd snap a couple pics and post this up to see if anyone has seen this before, or an explanation of the results..

Got a basic catch can from GSC a few years back, it's pretty beat now but you get the idea, in/out and a drain on the bottom, plus a little "sight glass" type of clear hose on the side so you can see if it is full..




The basic idea I had was that, in the other projects I've worked on, removing vacuum from the top end was a bad thing, so I wanted to keep the PCV system in operation, but at the same time, I didn't want any of the crap going back into the intake mani. So, this made sense to do both:




I was immediately shocked at just how much was accumulating in the can when I run E85, which nowadays is most of the time... on pump, not too much in there at all. But, on E85, this thing fills up in 1000 miles, no joke, I can empty it twice between oil changes, more if I'm racing alot.

It looks like this:

95% clear fluid that smells alot like ethanol

5%... baby poop? (some oil residue probably)






I hear alot about guys changing their oil the minute it "smells" like ethanol (that's another topic for another thread) and talk of "condensation" etc. etc with ethanol.. but I'm interested to know if any of the gurus on here have an explanation for what is going on there.. like I mentioned I am going to change this setup over the winter... but I am wondering with the normal catch can setup, is all that clear fluid hanging around in the oil then?


and no I won't drink what's in the can, even for 50 bucks

 

I really don't understand the logic you have on the installation of your catch can. Why would you connect the intake manifold and valvecover together in a sealed system?

 

The original lines can remain per stock routing, you just need to splice a tank into each line. Or just the PCV, but that still allows oil to go into your intercooler.
*The only difference here is that the breather now vents to atmosphere.

 

That's how it works stock, when the intake manifold is in vacuum, it pulls vapor from the top of the motor using the back port on the valve cover, where there is a PCV valve (check valve) into the intake manifold (look behind the return end of the fuel rail) . When you go into boost, the check valve shuts and air cannot get back into the valve cover. (in stock form the side port on the valve cover is connected into the intake pipe itself to pull vacuum under boost conditions, which is suppose to be good for emissions but in turn causes the intercooler to fill with oil residue)

All I did here was to run the hose between the valve cover and intake manifold through a catch can, which will still provide the vacuum to the top of the engine, but trap out the oil residue from re-entering the intake manifold.

I'm going to redo this with a totally different catch can setup that allows drainback of oil into the crankcase along with venting both sides of the cover


my main curiosity is what all the clear fluid really is, and what will become of it using a normal vented can

 

The clear stuff is mostly moisture that has collected.

 

Wow, that is a lot of crap! I switched to E-85 about 700 miles ago, so I just checked my catch cans, & I only had a very small amount of black oil. None of the clear fluid that you are getting. I will keep my eye on it after seeing this thread. I don't think that I would want to drain that back into my crankcase.

 

If you get a good can that seperates air/oil, you should recirc back to the intake. This would require two cans since you like having the pcv setup (as do i), but would help eliminate the milk shake.

 

I've been running a catch can the same setup, on E85 since 2008, and never had that moisture. I think a lot of it has to do with the region your in (dry verses wet climate). Have you checked your PCV to ensure the Ball is moving freely?

 

Yea sure did, I do a fair amout of engine decel when driving so maybe that is something to consider since that would put the greatest amount of vacuum on the top of the engine. Nevertheless, I'm going to switch to a setup like STM and Buschur run, that connects to both the top and bottom of the engine as well as venting... That will also keep everything out of the intake manifold which should help some also. Of course then I'm going to still be wondering about all this fluid and where it will be then!

 

looks like the campbells soup i just had.

 

Did the can have a hole in it or something?

 

Do you do a lot of short drives?

 

Here's what comes out of my catch can from running ethanol. Looks exactly like the E I put in it too hehe. Posted in another thread around here too, I forget which one. I don't have any of that floating yellow turd stuff though

 

Sometimes, I daily drive it at the moment.. I usually try to let it warm up almost all the way before driving it though

 

How is your catch can set up?