Smoke Problem

[Ashy]

Hi... Right any advice on my little problem...

Following on from THIS thread I've fitted a new engine (of unknown origin, I rebuilt it about 4 years agn but can't remember what I replaced or why). I did a leak through test with petrol in the bores before fitting and it was spot on. Clocked the head for flatness and used an uprated gasket.

So First I ran it with the original turbo and it smoked badly so I got hold of a known good T2 turbo and fitted that. The smoking improved but it was't right so I stripped it and re-built it. The rear oil seal had compressed so i thought a new one would sort it. It was much better, only smoking on gear changes and idle, no smoke whilst cruising. But I wasn't happy so fitted the old T3 off my old 172 engine... I knew that was absolutely spot as I'd recently rebuilt it and it never smoked on the 172.

Anyway the flipping thing still smokes.

Ive done a compression test and I get 151psi +/- 1psi on each cylinder.

The breather setup isn't standard, the non return valve in the inlet manifold is blocked so It cant be sucking oil vapur back into the inlet manifold. Theres very little crank case pressure at idle and I've had rings wear out on me before and this is a different type of smoke.

The think is i have removed the core of a T2 and blanked the front off so I could run without a turbo and I didn't get any smoke at all...

So I'm now totaly confused... Am I just having a run of bad luck? Could all the turbos just be knackered? could I have too much oil pressure (seems spot on on the stadard gauge) I'm running out of Ideas.

Current symptoms are, it smokes a little on boost but then theres a puff of smoke as I change gear... Also sometimes smokes at idle, not always, but it will smoke then stop for no reason then start again.

What should I try next?

Cheers Ashy.

[Scoff]

when you take the turbo's off, are they oily inside the turbine exit ?

if you're sure crank pressure is ok then stop/start smoking at idle is the turbo, no 2 ways about it!

[Fordy]

Is the Turbo oil return blocked?

[Brigsy]

Oil return to sump not blocked or kinked?

[James5]

when you take the turbo's off, are they oily inside the turbine exit ?

if you're sure crank pressure is ok then stop/start smoking at idle is the turbo, no 2 ways about it!

Looks like turbo Ashy

[Ashy]

I've made sure the oil reurn isn't blocked or kinked, only bit I havent checked is the metal part, guess some crud could be stuck in there?...

Each turbos always been primed plenty before use... I can't see how the turbos are always fine when they've come off one car and no good when fitted to mine (OK they've been stood a while in between use).

[GTphil]

Also Might be worth checking out the oil return pipe that bolts onto the gearbox, I had a bent bracket/pipe that was actually causing the oil from the turbo to back up as it wasn't flowing compleatly downwards.

I had a similar issue, my turbo was smoking so i replaced it with a bran new item and that smoked, sent it off to turbo developments and they said it was still as new and wasn't the problem.

I eventually stumbled across the problem when i held the pipe upto a spare one i had, it must have been pinched of knocked or something when i took the engine out.

Might not be your issue but worth a try

[Ashy]

Also Might be worth checking out the oil return pipe that bolts onto the gearbox, I had a bent bracket/pipe that was actually causing the oil from the turbo to back up as it wasn't flowing compleatly downwards.

I had a similar issue, my turbo was smoking so i replaced it with a bran new item and that smoked, sent it off to turbo developments and they said it was still as new and wasn't the problem.

I eventually stumbled across the problem when i held the pipe upto a spare one i had, it must have been pinched of knocked or something when i took the engine out.

Might not be your issue but worth a try

The metal one mate? I've got a spare on the red 5 so I'll whip it off and compare

[GTphil]

Yes the metal one

[TNT ANDY]

I feel this may resolve an issue for the masses

[Ashy]

I feel this may resolve an issue for the masses

Lets hope so

[Ashy]

Well I've swapped the oil return for a spare, both looked the same and I blew through them with no resistance...

The problems still the same.... So I'm gona take it all back appart and run it again (in the daylight the time) without a turbo just to make sure I'm not going mad!

I just can't believe that 2 turbos that were absolutely fine on two other 5's decided to smoke on old whitey....

[Sparkie]

just as a test before you take anything off. - completely remove the breather pot. and run the car for about 15mins. then take it for a drive and see if it smokes. without a blockage to the sump it may stop the smoke.

you also dont know what your oil pressure is.... maybe you have a low oil pressure turbo killer engine.... complete with added swarf...

[Ashy]

just as a test before you take anything off. - completely remove the breather pot. and run the car for about 15mins. then take it for a drive and see if it smokes. without a blockage to the sump it may stop the smoke.
.

Just the breather pot mate?

Aye, could be low oil pressure although it registers good pressure on the reno gauge... I'll get a seperate gauge setup.