Hope it's the Turbo !

[Jap-Car]

Hi,

Has anyone ever had a turbo fail but for play in the shaft to still be minimal (none axial, <1mm radial at end of shaft) and for it to turn smoothly by hand?

I'm thinking that the turbo seals have failed as once the engine is warmed and when revved, lots of white grey smoke from the exhaust. Also loads of oil in the exhaust at the exit from the turbo. The oil could be coming from the engine but i would have expected the smoke to be blue in colour. However, I expected to find loads of play in the turbo.

Thanks for any help,

Robert

[Jap-Car]

Thanks for the replies.

So nobody has come across a turbo with leaking oil seals but negligible play in the shaft?

I've just replaced the head gasket as the cooling system was being pressurised. Now it's not pressurised so I'd be surprised if it is steam.

Axial play in the turbo is negligible. Radial play is not enough for the wheel to hit the housing.

There is loads of oil in the exhaust at the exit from the turbo so I assumed that the smoke was vapourised but unburnt oil (it only happens once the engine is warm and then not at idle)

There's no oil on the glow-plug or injector tips (it's a diesel) which I took as a good sign of it being the turbo at fault rather than the engine itself. When I had the head removed to change the gasket, there was no oil in any of the cylinders.

Cheers,

Robert.

[Jap-Car]

Thanks guys,

I am going to get another turbo. I'll post on here to let you know if its fixed. (or if it doesn't, to sell a spare turbo!!)

Cheers,

Robert.

[Jap-Car]

Another symtom is that the sump is pressurised. If I remove the dip-stick, i get a flow of oil from the engine. Yesterday I dropped the oil pan and cleaned out the gunge (from when the head-gasket blew) from the pan and from the breathers.

I haven't re-tested the engine as the exhaust manifold and turbo are off but hopefully this will sort the pressurised sump. (I don't think this is piston rings as the compression test is good and there is no sign of oil in the exhaust manifold before the turbo).

A thought which has just crossed my mind though, could faulty turbo seals also cause a pressurised sump? Ie compressed air or exhaust gas being sent down the oil return pipe which feeds direct to the sump.

Anyone think this is plausible?

Thanks everyone.

Robert.

[Jap-Car]

Thanks for all the replies. I'll tell you the full story! This may be a long post - sorry.

The car is a Toyota Lucida 2.2litre turbo diesel.

I bought the car as faulty from the previous owner who I believe is entirely honest. He e-mailed me the following information (after I had bought the car so no need for hime to make up a story)

"The problem only appeared on one day when it overheated, and lots of steam appeared came out - we drove about quarter of a mile with the car overheating just to get it home. But that was the first time there was a problem, and the last time it was driven before the head was changed (the head was diagnosed as cracked - a common problem on these engines). When we picked it up after the change it smoked badly - probably drove about a mile and a half before it got so bad. Then we took it to the other garage who cleaned out the engine and did an oil change. We drove it about 60 miles with little or no smoke, then a few days later when we started it up it was bellowing again, and it was not driven again."

At this point I bought the car. I warmed the engine up and found dense clouds of white/grey smoke (no trace of blue) to be emitted from the exhaust when revved and warm (ie little or no smoke when engine cold or when at idle). I did a compression test (with engine warm) and found all cylinders to be good.

I noticed that the coolant system was slowly being pressurised so I replaced the head-gasket with a genuine Toyota item. The coolant system is now no longer pressurised. (I think the previous gasket was for a slightly different engine hance the leak). I re-ran the engine expecting the fault to be fixed but it still smoked just as badly.

Then I noticed that with the dip-stick removed, oil is slowly forced out of the dip-stick hole. ie a pressurised crank case.

Next I removed the exhaust manifold and turbo and found the exhaust manifold to be damp inside with a liquid which I assume was water as it has since evaporated and now just dry and sooty. Also the exhaust exit from the turbo was covered in oil. A similar unit on my friends car has no oil ie it also dry and sooty.

I have also removed the sump to find the oil to be OK ish but with about 1/2" of sludge at the bottom. (No metal particles in the sludge though). The breather (crank-case to air intake) was also filled with sludge and some water. The intercooler also has pools of oil and water within. Obviously I'm cleaning all this out.

I have ordred another turbo and am hoping the smoke was from oil leaking from it's seals into the hot exhaust. I'm hoping the water in the exhaust manifold was from all the water still in the air intake system from the previous head-gasket leak via the breather system. I'm hoping the pressurised crank-case was from blocked breathers.

Turbo should arrive Fri / Mon so will know for sure by the middle of next week.

Any more views??? Please don't tell me piston rings!

[Jap-Car]

I'm pretty sure the water in the intercooler is from the cracked head / blown head-gasket allowing water into the oil and then on through the crank-case breather to the intake air stream just before the turbo. I'm positive that the coolant system is no longer leaking so I'm sure the water is from previously.

I've ordered a 2nd hand low mileage turbo from a company that brings them direct from Japan. A friend has used them before and the stuff they supply is good. £150 all in seemed a good price also.

The most worrying thing is the pressurised sump. I just hope it was either blocked breathers or something weird with the turbo sending air down the oil return pipe (although I share the doubts expressed above). I would have thought that worn piston rings would have shown up on a compression test but I guess a crack in the head or leaking head gasket between oil channels and combustion chamber might be the cause. I would have thought I would have seen blue smoke though (ie burnt oil).

Thanks for all thoughts so far

[Jap-Car]

Too late jv It's on its way.

I guess at worst, I'll have a spare turbo and the chances of getting too with the same fault must be slim.

[Jap-Car]

As promised, an update.

I've changed the turbo, cleaned the oil pan, intercooler and associated pipes. New oil and filter. Car still has the same symptoms. Ie fine when cold but once starting to warm, pressure develops in the sump, white/ grey smoke from the exhaust and fluid (I now think an oil / water mix) dripping from the exhaust at a hole (where the turbo actuator arm happens to pivot).

Obviously, something is either wrong with the block (worn bores / piston rings / warped) or head (cracked / warped) or head gasket. Any ideas how I can tell which and also if water is escaping to the exhaust, why is the coolant system not getting pressurised?

Please help!

Thanks

Robert

>> Edited by Jap-Car on Friday 10th October 12:52

[Jap-Car]

I thought of that but can't understand why I should get lots of water in the exhaust from fuel when other cars don't!

Thanks though

Robert.

[Jap-Car]

Thanks for your thoughts. I ran the car some more at the weekend. As some of you guys suspected, the water turned out to be residual water in the system. It dissapeared after running for another 30 minutes.

Now the only symptoms are a pressurised sump and a some blue smoke (which is reducing, I guess as stuff burns out of the exhaust system). I believe this is probably therefore piston rings / bores, particularly as I did notice some damage to one of the bores when the head was off. (Although the compression test was good)

Question - has anyone come across this type of damage before? It is deep (2mm) erosion / pitting over the top 5 mm of the bore and for about half the circumference. I decided that it stopped just short of the top piston ring but maybe the damage was more extensive than I thought. The damage was in the cylinder where the head originally cracked which may or may not be coincidence. Thoughts?

Cheers,

Robert.

>> Edited by Jap-Car on Monday 13th October 09:57

[Jap-Car]

Yeah, piston looked absolutely fine. when I rotated the engine by hand with the head off, everything seemed nice and smooth. I don't think the engine has stood for very long with water in the bore but it's possible I guess.

I wondered if it was due to either erosion as water / steam entered and exited the cylinder or perhaps water encourages pre-detonation (I'm out of my depth on that subject).

Obviously, I wish I'd measured the bore but I didn't. Is there anyway of telling if the problem is with the rings or the bore without a strip down?

[Jap-Car]

Thanks Mike, but how does the wet / dry compression test tell me it's rings rather than bore?

Cheers,

Robert.

[Jap-Car]

Thanks,

I wonder if I could do a leak-down test at TDC and also at Bottom Dead Centre (or are one or the other valves open at this point?). My logic is that by comparing leak-down at top and bottom and across the cylinders, I might be able to tell.

I know that bores don't generally wear near the bottom and the volume of gas would be larger and therefore leak-down rate would be different. However, if say leak-down at top and bottom was markedly worse on one cylinder then that would imply rings. Whereas if leak-down is only worse at the top then this implies bore.

My reason for wanting to be sure before removing the head is that if it is the bore, I might just leave it as this would effectively mean a new engine which is a lot of work and money.

Is the inlet valve still open as the piston reaches the bottom of its stroke?

[Jap-Car]

Mike thanks again for your thoughts. I think my valve clearances are set by shims beneath the cam so back to the drawing board! I guess I could try and hold the engine in place half-way down the power stroke and make a leak-down test there.

I guess I'll try for an MOT first and decide what to do depending on if the emissions test is OK or not.

Thanks everyone.