New Motor Blue Smoke

[Old Fart]

Hope someone can help.

I just had an exchange engine fitted to my D40 and now it runs fine for about 1 kilometre then there is a big puff of blue smoke and then the blue smoke continues. However if you stop and turn off the engine and restart it immediately, there is no smoke until it has been running again for some time.

 

[Old.Tony]

I wonder if the turbocharger is doing it? Leaking seal? Excessive blowby (this should not be the case)?

If you had a mechanic do the work, it's probably worth taking it back.

 

[bods]

I wonder if the turbocharger is doing it? Leaking seal? Excessive blowby (this should not be the case)?

If you had a mechanic do the work, it's probably worth taking it back.

This seems to be a follow on issue from the 5 turbos thread, so it would seem there is another underlying problem somewhere...

 

[jonney]

i wonder if something is building up pressure then when switched off the pressure drops and all is fine again for another k. from what i have read is the Blue Smoke blow is mainly caused by the Turbo and or areas .

 

[Old.Tony]

Blow-by is what we call the gas that escapes past the piston rings, enters the sump (crankcase) and pressurises it. Without the PCV (positive crankcase ventilation) at the top of the motor, the crankcase would continue to build pressure until something popped - usually a dipstick.

As an emission control measure (old engines didn't have this and you'll find the PCV is just a breather cap on the top of the motor) they decided to route the blow-by into the intake manifold. Caburettor engines had this connected directly to the intake manifold unless they were turbocharged or supercharged. Once you apply positive pressure to the intake manifold, you need to connect the PCV to the pump's (turbo/supercharger) intake. Ours is just before the turbo.

There might be something in your theory though. What if the oil lines to the turbocharger are blocked? What if it's the oil return line from the turbo? These may have been assumed to be in good order simply because they're just pipes and what can go wrong with a pipe ... ask a plumber that one, I guess!