Blue smoke VW TDI 150-5

[Martinbruvik99]

Hello,
i have a marine TDI 150-5 engine in my boat.
The engine makes a lot of blue/grey smoke at startup,
and when the engine temp is normal it makes quite alot of blue smoke at idle/ low rpms.
however, when i rev it up and the turbo kicks in it seems to dissapear, and when i go back to idle again it takes a minute or two before the blue smoke is back.

any tips?

 

[jmodge]

Sounds like it could be valve guides, is there a lot of hours on it?

 

[Martinbruvik99]

Sounds like it could be valve guides, is there a lot of hours on it?

just passed 1000 hours, the smoke has become alot worse the last 50 hours

 

[jmodge]

Not very high hours then. Oil level dropping? Could be be turbo seals, I hear it’s difficult to keep them cool in a boat. If so, that condition could result in a runaway. Shut it off during a heavy smoke cycle and pull the boost pipe from immediately after the turbo to see if it’s full of oil. Or even just do it now and idle it open to see if oil sprays out, That would prevent the engine from ingesting it and running away

 

[Martinbruvik99]

Not dropping alot i think, im not a engine expert, not even sure what a boost pipe is.
Will try to figure it out and have a look

 

[jmodge]

In your shoes it may be best to find a mechanic. At any rate, I would suggest not running the motor with that condition, it could lead to uncontrollable acceleration.

 

[jmodge]

Unless you have time and inclination to learn. On the turbo will be two large hose or pipe connections. One will draw air FROM the spark arrestor or whatever intake setup you have. We will call that the intake tube. The other will be exiting the turbo with compressed charge air heading to the intake of the engine. We will can that the boost or charge air pipe. The charge air pipe is the first to check. If full of oil, you have a turbo problem.

 

[jmodge]

You will also notice a small braided or solid steel line running to your turbo. That is oil supply to the bearings in the turbo. I suspect internally excess supply oil is making it past the bearing and being ingested and burnt along with fuel by you engine causing the smoke. This excess oil is unmetered and can act like an uncontrollable throttle response. Google Diesel engine runaway for videos of what you don’t want to happen to your engine

 

[Martinbruvik99]

Will have a look tomorrow, the oil level has dropped approx 1-1,5 mm in 50 hours of use

 

[Martinbruvik99]

You will also notice a small braided or solid steel line running to your turbo. That is oil supply to the bearings in the turbo. I suspect internally excess supply oil is making it past the bearing and being ingested and burnt along with fuel by you engine causing the smoke. This excess oil is unmetered and can act like an uncontrollable throttle response. Google Diesel engine runaway for videos of what you don’t want to happen to your engine

Had a look at my turbo today, found some oil on the intake tube on the turbo, seems like it comes from the crankhouse ventilator?

19A3F592-95A4-42A7-BFFF-261B51F9A8DE.jpeg

• Martinbruvik99
• Oct 18, 2020

F6EAD5BD-0042-4EDC-9183-FF9D60F06F50.jpeg

• Martinbruvik99
• Oct 18, 2020

took some pictures, wich one is the boost pipe?

91297AD4-FAF1-4A03-8EF4-679CA51EE9B8.jpeg

• Martinbruvik99
• Oct 18, 2020

D6C48A38-9073-4F49-8122-334CE4F634DF.jpeg

• Martinbruvik99
• Oct 18, 2020

 

[jmodge]

I am assuming that top photo is a view down the pipe leading to the center of the turbo cartridge and your crankcase vent feeds into that pipe? If so, I would think some oil there would be normal. The charge pipe should be the short curved hose going to the intake manifold., check that one for excess oil. Excess blowby could be another cause of smoke. Do you get the impression the smoke is from oil and not partially burnt fuel? On that last picture what is that line running across the housing of the turbo just past the last "T" on GARRETT?
Not familiar with marine engines, nice pictures, turbo looks like it has a coolant hose going to it. What size engine is that? I think there is a fellow that goes by the handle of Picklerick on this site that works on these. I can help you with a general diagnosis, if specific details are needed to that engine he can hopefully assist you.
So to summarize, determine if you are making smoke from oil or fuel. Check both sides of the turbo to determine if you have excess oil entering or leaving the turbo. If so, determine the source. Entering would most likely be blowby, leaving would most likely be turbo seals.
At any rate, I would not start the engine with the charge pipe connected to intake manifold.