Oil catch can for a Weber set up

[SynthDesign]

After driving the General for a little over 13k, I realized my plugs were quite fouled. It's also been running rich. The air filter for the Weber carb was covered in oil. It appears under high RPM, the oil breather tube is sucking in a fair bit of oil. My solution was to install an oil catch can to collect the excess oil that was being sucked into the carb. For about $30 and a bit of time, I had an easy solution.

I picked up the cheapest catch can I could find on Ebay, $15.00 shipped. It came with a viewing tube which I didn’t like so I simply deleted it with two pipe fitting plugs. I took it all apart and resealed it with FIPG.

catch can 1.JPG

I drilled out and replaced the rivets on the tanks, sandwiching the stainless steel plate between them.

catch can2.JPG

A few feet of 3/8” oil cooler hose and it came together easily and I think looks decent.

catch can 3.JPG

catch can 4.JPG

catch can 5.JPG

The test will be how much oil is collected after the next oil change. I'm sure this could be adapted to a stock carb setup as well. Let me know if anybody wants my template and I'll scan it.

[ARCHINSTL]

That's interesting - I've been thinking of that for a while, although more of as a "C" item to do - and actually on the PCV tube. I've had the breather tube hooked to the Weber cleaner (although not by its Micky Mouse plastic fitting) for 3 1/2 years now and have yet to notice any oily residue on the inside of the cleaner.
Tom M.

[SynthDesign]

I'm using a little K&N filter on the PCV valve and have never had problem with that leaking.

[Petros]

I have never had this problem with any car I have owned, usualy a new PCV fixed any issues. are you sure there is not something else wrong your engine? Excessive blow by perhaps?

[xirdneh]

I had it happen to one engine.
Had forgot to drain oil and added another round of oil.
Way Too much oil in there.

[danzo]

Like xirdneh, the only time I've ever had this problem was when I overfilled a motorcycle with oil. Sounds like you may have another issue.

[larry mcgrath]

synth: Looks like a compression test is in order (a broken ring?)

[Petros]

You might see if you can measure the pressure in the crank case (from the dip stick tube perhaps?). THere is a specification I think in the FSM for the max pressure in the crank case.

[SynthDesign]

Compression is fine. Engine runs great and pulls strong. Only issue is a slight exhaust leak.

The other thought is very few have engine that are rev'd around 6k plus on a regular basis. Could that be the cause?

So far it seems some of you guys think this is a useless item. They've proven to be very useful on AW11 MR2s using the 4A-GE. Without using one the intake runners look like this after 150k of driving.

4age runner 2.jpg

4age intake.jpg

[SynthDesign]

Ok, under paranoia I checked the compression again.
Max under hard 3 sec crank w starter
172psi
175psi
182psi
178psi

Max crank case pressure is just under 15psi @5,00 rpm
Max vacuum at air filter, unregisterable @5,00rpm

[Lil Beast]

I do have the problem sometime going 150+ in the curves, you can see huge thick blue smoke sometime! Especially in a long left curve, the head fills up with oil cause on the pressure and breather just sucks it in! A catch can is the solutions! 4age's are known for the head to over filled at high rpm! Same with 3a its the way the oil is fed! Some put a dry sump pump and feed from top to reverse the process and avoid the smokin blue high speed cornering! I always have one side of my air filter full of oil, bought a cheap can from ebay too, so I'll put it to the test too!

[Petros]

it has always been common practice on race cars to eliminate the oil sump, go to dry sump with scavenger pump. Oil is stored in large side tank in engine compartment. Often when oil sloshes in sump to side in high-g turn you foam the oil when crank strikes it. That will cause oil to go in all kinds of places it is not supposed to go, including the breather. Splashing up cylinders will cause extra oil to burn too and smoke like crazy. With transverse engine install this problem even worse than old standard install.

I have never owned a street car with enough cornering capacity to cause this, but many of the race cars I helped build did, but I would find it questionable to need it on any kind of street car (other than to show off to your friends the "cool" dry sump oil system). I am surprised Toyota did not accommodate this issue with the MR2, which has a very high lateral acceleration capacity even if fully stock form.

[Lil Beast]

Mr2's are bad this is the intake of the engine I got! Oily as hell, gas goes thru there kinda odd!

mr2%20intake.jpg

Seeing this makes me want to remove the head and clean, but I'm scared it will warp on me! I'm a rotary! No head to fool around! Should I ? And replace with a copper one?

[Petros]

you will not warp the head by removing it, just follow the FSM torque sequence. But I would just soak the combustion chambers in Gumout or Seafoam overnight, and than run it to blow out the softened carbon. Usually works. Even injecting water with the engine running at high rpms (use a spray bottle down the intake) also can clean out carbon.

lot easier than removing the head.

[Lil Beast]

Yeah that's what I was thinking at first try that seafoam stuff and see what happen after! My compression is at 165psi+/-2 all around! I used water too before on my rx-7 cause of the oil injectors in the rotary, I had mine adjusted to squirt a little more for high rpm lubing but the engine was getting dirty quick! I'll save the copper gasket for a high comp rebuilt in time!