Oil Catch Tank Smell Ideas

Hey all.

I have a whifbitz oil catch tank and have both cam cover breather lines going into it.

This causes a smell of fuel through the vents so I took the filter off and used some silicone hose to extend the filter under the brake servo.

Its definitely reduced the smell but remains when stationary once the car has warmed up.

Has anyone else experienced this or have an idea were to vent it to?

I know a lot of people have AN fittings welded onto the crank case and run lines to the back of the car but I don't ant to go down that route.

Thanks

Paul

I run a third AN line to the Airbox or you could run it to the Sump, but a smell of fuel? Is she running rich? Oil contamination ?

Sounds like oil contamination... Have no idea though

Hey all.

 

I have a whifbitz oil catch tank and have both cam cover breather lines going into it.

 

This causes a smell of fuel through the vents so I took the filter off and used some silicone hose to extend the filter under the brake servo.

 

Its definitely reduced the smell but remains when stationary once the car has warmed up.

 

Has anyone else experienced this or have an idea were to vent it to?

 

I know a lot of people have AN fittings welded onto the crank case and run lines to the back of the car but I don't ant to go down that route.

 

Thanks

Paul

I had this same issue. In the end I just removed the catch can and ran it under and back of the car. Like you mentioned you don't want that and the other options is what Jellybean mentioned.

Because I was going to vent it into the sump but I thought more hassle and there be more clutter in the engine bay, so I just ran it under.

I have never had any smell of fuel, no matter where I situated the catch can, I would either be looking into the cause, or it could possibly be as a result of removing the carbon canister and not relocating the fuel tank vent.

I have never had any smell of fuel, no matter where I situated the catch can, I would either be looking into the cause, or it could possibly be as a result of removing the carbon canister and not relocating the fuel tank vent.

You make a very good point. I don't think I did that when I removed my carbon canister, I might try this when I get some time and see if that stops the smell completely.

Like I said before Paul, we are always doing the similar things on the Supra

You make a very good point. I don't think I did that when I removed my carbon canister, I might try this when I get some time and see if that stops the smell completely.

 

Like I said before Paul, we are always doing the similar things on the Supra

lol supra menstruation cycle

Well it started once I added the inlet cam cover hose. And I assume that because the air pressure now going into the tank causing it to blow the vapour out of the breather.

I have read on-line its rather common for a oily fuel smell to come from catch tanks and as its right next to the scuttle were I believe the air is used for the vents.

When I drive its not there.. Due to natural winds I suspect. But before I moved the air filter breather the smell was always there regardless.

I have indeed had the canister removed but its not that as I have located it, and I can actually smell the vapour from the filter.

Thanks

You really have only three options.

1. Leave it as it is

2. Vent it under the supra

3. Vent it into the sump/oil return/ air filter (wouldn't recommend in venting into the filter which flows into the turbo but each to there own)

Do update us if you find another route and also which one you choose in the end

Option 3, but it should go back into the turbo intake, as this will make use of the normal high load PCV side of the system and not only eliminate any oily/fuel smelling odor, but help with ring seal at high loads, for some reason people seem to forget that if you add a proper sealed and baffled catch can, any oil vapor will drop out so its quite safe to plumb back into the turbo intake, and not get oil back into the intake, which was the whole point of fitting a catch can.

However I would still be investigating the cause of the fuel smell, as normally you shouldn't be getting that from a catch can unless there is serious over fuelling.

Thanks fellas. Really liking the idea of plumbing into the air filter. I have seen that before.

With the over fueling idea my afr is always in the 14's mainly 14.7 which is pretty normal...

I hope its not always 14.7 you should be seeing 11.2-11.8 under load/boost.

Take the oil cap off, have a smell for fuel ; you definitely do not want bore wash , eliminating the lubrication of oil from critical components like the trust, big end bearings

I hope its not always 14.7 you should be seeing 11.2-11.8 under load/boost.

lol absolutely the, numbers drop under boost.. As I said the fuel smell is mainly stationary when its at 14.7 and slow driving

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Take the oil cap off, have a smell for fuel ; you definitely do not want bore wash , eliminating the lubrication of oil from critical components like the trust, big end bearings

Thanks mate will check that out, during my oil change a week or 2 ago no fuel smell coming from the sump..

Hot oil smell, yes, so long as it wasn't showing excess blow by or smoking at all. Fuel smell? That would concern me.

I never like asking an engine to breathe its own fumes, and would put up with the smell on a high power, modded unit. Mid eighties cars used purge valves to run fumes into the exhaust using a venturi effect, but it's more to go wrong and probably you'd be as well using the stock PCV valve set up if it bugged you that much.

Rather than just point the breather pipe out of the back of the car, which I find abhorrent, would otherwise be feasible to run it into the windscreen scuttle area?

You could do what Hodge did in the early days of his build. Put a custom catch can in the inner wings.

Thank fellas.. I've ordered a 19mm silicone pipe to run into the air filter pipe.

No smoke at all from the filter. I think hot oil and fuel smell I could be getting mixed up. Just smell fumeu.

Thats awesome Dim Sum will see how this 19mm goes

Quick update on this, My friend welded on the 19mm connection under my air filter intake pipe and I routed it all up with the oil catch tank.

So far no off smells

And some pics..