Thread: Burning oil smell

Originally Posted by 110Landy86

As the title suggests.

I can smell burnt oil after driving. Never had this prior to fitting the turbo. I'm thinking oil is being burnt in the turbo/ dump pipe.

Minimal exhaust smoke visible.

I have a flow reducer in the turbo feed line - perhaps oil is passing through turbo seals - need to reduce flow further?

Turbo oil return via 1/4" BSP tube is to pump housing (as others have done)

Any ideas as to how I can fix this?

Much Appreciated

Which pump housing?
If you mean the vacuum pump housing then thats a known bad idea as it doesn't drain fast enough.

Steve

1/4" BSP is very small for a drain.

Sorry I mean oil pump cover. Definitely not the vacuum pump oil return.

I'll confirm the oil return size.

Had a chance to measure the turbo oil return pipe today. ID is approx 13.5 mm. Is this too small for oil return?

Thanks

Originally Posted by 110Landy86

Had a chance to measure the turbo oil return pipe today. ID is approx 13.5 mm. Is this too small for oil return?

Thanks

That's plenty for the pipe, but from memory its not physically possible to get that diameter into the oil pump cover - so its likely to be restricted to whatever size fitting you have there. From memory mine was 3/8 BSP and I couldn't go any larger.

Have you got a photo of the fitting and where it goes into the pump cover.

Steve

Hey Steve, I have brass 3/8 BSP 45deg fitting into the oil pump cover. I have replicated the entry position w.r.t the oil pump cover, as shown in various threads on here. I figured there would be a small increase in flow restriction at the fitting so I enlarged the annulus marginally by drilling it out.

As you mentioned, with the 3/8 BSP fitting there isn't much wall thickness at the critical point (say ~3 mm).

The turbo was purchased brand new and has done ~8000 km. AFAIK there isn't any/ very minimal turbo shaft play.

Basically, I get the smell after its been working hard.

I was thinking of doing one of the following:

1. Further reduce the turbo oil feed flow rate (already have a flow restrictor installed in turbo feed); or
2. Install a Y-piece directly after the turbo and run two 3/8" (ID) outflows. One to the oil pump cover and one into the sump through a one-way valve. Are there any locations that are more favourable/ easier to access?

Appreciate your thoughts.

Cheers Joe

Sure you don't have any external leaks onto the turbo, manifold or exhaust?

Hey Ben, not that I know of but I do have minor oil residue visible at the charged-air side at the mating surface between the turbo and the intake pipe.

This suggests to me that either I have some oil-rich passing through to the intake manifold or simply heating up to a point where the oil burns (and consequently smells) when the charged air plumbing gets hot.

Just bouncing a few ideas around

Cheers