mystery smoke...

[turbotommy]

I've had the joy of owning a UK '96 3.0TD for one year (after 6 years in US with an '86 4runner), and have recently been having much grief with white/blue smoke. Does anyone have any ideas ?

This vehicle has 75K on the clock and compression of 280-/+10 on each cylinder, i just had a new turbo fitted, and still there is some smoke though it got a lot better (and it accelerates much more...). What's really weird is that it seems to be variable and almost intermittent, suggesting that it is not a busted piston ring, or knackered valve guides. It is worse when cold, and seems to be mainly at idle or pulling away, not under deceleration or when accelerating while moving. It looks like the head has been replaced, as well, which is odd for so few miles (previous cracked head or stuck valve??). Also i've had the injectors cleaned/serviced as it was knocking a lot. I'm wondering if it might be the injector pump, or possibly the crankcase ventilation system.

Has anyone else had something similar ?

[Guest]

I've had the joy of owning a UK '96 3.0TD for one year (after 6 years in US with an '86 4runner), and have recently been having much grief with white/blue smoke. Does anyone have any ideas ?

This vehicle has 75K on the clock and compression of 280-/+10 on each cylinder, i just had a new turbo fitted, and still there is some smoke though it got a lot better (and it accelerates much more...). What's really weird is that it seems to be variable and almost intermittent, suggesting that it is not a busted piston ring, or knackered valve guides. It is worse when cold, and seems to be mainly at idle or pulling away, not under deceleration or when accelerating while moving. It looks like the head has been replaced, as well, which is odd for so few miles (previous cracked head or stuck valve??). Also i've had the injectors cleaned/serviced as it was knocking a lot. I'm wondering if it might be the injector pump, or possibly the crankcase ventilation system.

Has anyone else had something similar ?

White smoke indicates water, blue smoke indicates burning oil. Most Surfs have a small amount of oil blowby from the crankcase ventilation. You can check by removing the turbo to Airfilter and turbo to inlet pipes and checking for the presence of oil in the pipes. There will be some but there shouldn't be too much.

You may want to put an additive in the fuel (although injector blocakge is indicated by black smoke on acceleration and when starting). Redex or Wynns injector cleaner is good. 1 large bottle to 1/4 tank will give it a good blowout.

You may have a small amount of ring wear which depending on when the head was replaced and whether they did a full decoke when it was done, could mean that you are getting some pressure buildup in the crankcase causing more blow by or oil seapage into the cylinders. This often goes as the engine beds in after a decoke as it builds up the carbon ridge around the top of the bores.

It really depends how much smoke you have, all Diesels smoke to a certain extent, most diesels burn a bit of oil.

As long as the temperature stays OK, the power is good and the oil pressure is good then I wouldn't neccessarily worry too much unless you are using large amounts of oil. May be worth checking how much oil you use over 1000 miles, my 2.4 uses about 1/2 pint between oil changes.

Intermittent faults like this can be things such as valve guides, rings etc because as the engine warms up then the clearances change, things expand etc and generally leak less.

Cheers

[turbotommy]

Thanx, Andy, I'll see about measuring oil comsumption, but it does seem to use a bit. The numpties in the place that did the turbo overfilled the oil anyway, so i need to drain it and start again.

Once upon a time i used to do all my own work, but the arrival of a sprog and the lack of a garage have put an end to that. My local Toyota dealer had absolutely no interest in checking the compression, and claimed that they didn't have a gauge that went high enough for a diesel. Can you believe it ? Of course, all garages love it when you ask key questions like 'so exactly why do you think it is....' My first experience with a garage (arnold clark) suggested that the big end had gone, though doing the injectors magically fixed the knock.

I'm dearly regretting flogging my '86, but it was a 2-door and the wife didn't like driving a left-hooker over here.