Makeshift Oil Catch Can
 

This last January, our fellow forum member, GEE PASTA, posted a thread on a makeshift Oil Catch Can. He noticed that when working on the lower collector, there was a small amount of oil in the said. I had noticed the same when installing the MREV+ back in October. Subsequently, other members had posted about the same experience.

https://g35driver.com/forums/showthr...=oil+catch+can

At that point, I gave serious consideration to installing a Stillen Oil Catch Can. However, due to its size, I did not know where to install it.

Just recently, our friend, DaveO found a great thread in a FX forum,which dealt with this issue. DaveO posted his results and pics of his makeshift oil catch can for his Z.

https://g35driver.com/forums/engine-drivetrain-forced-induction/97246-catchin-oil.html

I took DaveO's lead and have done the same. Many have stated that this is not neccessary. That may or may not be true and I will not argue that point. Nonetheless, for those of you whom may have concerns with regard to this issue . . . Here is my makeshift Oil Catch Can DIY.

Attachment 224764

The parts needed and shown above are:

1. 2 - 1/4" dia. threaded (male) to 3/8" barbed fittings
**Edit: 2 - 3/8" elbows and 2- 3/8" x 1" nutted nipples
These additional parts are reflected in the pics in post #46.
A 16 gauge anodized Aluminum bracket was added, as well.
2. 2- 5/8" hose clamps
3. 2 feet of 3/8" dia. Fuel line hose **(edited: After some 3 days of using the fuel line hose . . . I swapped out the said for fuel injection hose. This new hose prevents the hoses from collapsing during idling rpm and may prevent the "Sucking" sound, which some have experienced.)**
4. 1- Mini All Purpose Filter with 1/4" dia. threaded female connectors

The 3/8" dia. fuel line hose was purchased at Kragen for $2.40. Everything else was purchase at Home Depot for some $17.00. So, this quick and easy mod cost me less than $20.00. ;) :D


Note: The filter comes with comments reading . . . "Avoid synthetic oils, chemicals, solvents, paints and fumes which may cause bowl failure."

Attachment 224765

The above 3/8" dia. hose needs to be removed. This existing hose connects to and from the PCV valve and to the fitting at the lower collector, which is shown.

Attachment 224766

This is what it looks like after the existing hose has been removed. Note the oil residue at the base of the yellowish PCV valve.

Attachment 224767

Apply some white teflon tape to the threaded portions of the 2 - 1/4" dia./3/8" dia. fittings and thread them into the filter. Note the "ARROW" stamped on the filter housing. The arrow is the side of the filter which will be connected to the lower collector.

When all is said and done . . . The following pics are the final product. This little project took all of 30 minutes including the snapping of the pics.

Attachment 224768

Attachment 224769

Attachment 224770

I reused the existing hose clamps at the PCV valve and lower plenum connections and used the new hose clamps at the new filter assembly.The glass bowl is easily removed. When removing the bowl, note that there is a thin rubber "O" ring, which can fall out. The entire assembly can be removed at the PCV valve and the lower collector connections in a matter of seconds, if one should wish or need to replace the existing OEM hose assembly.

Thanks to GEE PASTA for pointing out a potential issue . . . And thanks to DaveO for digging up the info to afford me a very simple and cost effective mod. ;) :D

Andy,

A great DIY. Are you planning on removing the (white) filter element? I would think it would become saturated with oil and end up blocking or at least limiting flow into and out of the bowl.

Your thoughts?


DaveO

Actually, Dave . . . That was a concern of mine. I don't want to prevent the oil from dropping into the bowl. I would assume that it either simply twist off or pops out . . . I'll take a look. Thanks again, Dave. ;)

Edit: That was easy. The filtering element simply twisted right off. Now, nothing should impede the flow.

Excellent instructions, Andy.

I'm gonna be doing this when I get my mrev++.

Thanks again!

You are quite welcome. The DIY was the natural progression of things. Having had the interest already and with all of the help from our buddies . . . I would have been remiss if I had not posted the said.

nice mod

I assume the G is setup similar to the Z. In that case, what about the other side? There is a vent tube from the other rocker cover that ties into the intake tube. Everybody blames it for depositing an oily film on the throttle body, intake tube & plenum neck. Shouldn't you put one there also?

Yes, that would be the emissions tube. I have taking my Z tube off and have had the opportunity to see the TB and the plenum neck a handful of times in the past year . . . I have not seen any oil residue yet, as such. I will be taking off the upper collector soon and will see if any residue has settled in the last 4k miles.

I totally agree Andy.

It's my opinion that the source of oil is from the PVC valve to the lower collector's oil gallery. I've never observed any oil in the vent hose to the air intake tube. Has anyone else?

The black gummy residue that collects around the throttlebody's brass butterfly comes from gas and oil vapors condensing on the internal or back side of the butterfly. That's basically a normal thing and provides the dealer and opportunity to sell you a cleaning service. If allowed to build-up over time the engine can idle roughly and surge under low throttle conditions.
(My thanks to JW for confirming my thoughts on this subject.)

DaveO

I didn't see any oil in the vent hose ever...

Some people report seeing the oily film in the intake/TB and others don't. According to the FSM, vapors normally flow through the PCV into the intake while fresh air is drawn from the intake tube into the crankcase. In "high load"/high RPM operation, the blowby can't be handled by just the PCV line so it actually gets drawn back through the line from the intake tube.

Andy great write up! After checking out my "cheap" setup from the past, I have discovered some oil in my filter setup. With the small amount of miles driven, IM surprised how much oil has built up. Your setup is sure a more permanent solution. Andy, DaveO Thanks

Dennis, you are the one whom started me thinking about this issue . . . And DaveO simply made it too simple for me not to investigate the matter more.

I drove a total of 24.1 miles, today. This was half/half mileage to and from work. As soon as I got home, I checked the catch bowl. There was a good 2 to 3 drops of oil sitting at the bottom of the bowl. Now, I am wondering how much oil vapor got passed through this set-up.

If nothing else, I know for a fact that this oil catch set-up is working and catching some of the oil vapors . . . Which if anything else, cannot hurt matters.

Might have to make one this weekend... great DIY

BTW is this for modded VQ's or is this suggested for stock VQ's as well?