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  #1  
Old 12-24-2020, 08:25 AM
Sethsquatch Sethsquatch is offline
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Default Pinzgauer woes...

OK so! Finally got my Pinzgauer from the shop, engine was running like a champ, the mechanic was able to talk to a technician in the UK who walked him through adjusting the fuel pump, and it was running good.
I picked it up and noticed quite a bit of black smoke as I was driving. (later the mechanic told me it barely was smoking when he had it adjusted.)
After driving 20-25 mins, there was a *clunk* sound from the engine, and the clattering actually got much quieter from the engine. I figured the noise was typical diesel, I hadn't driven it in 5 months, so didn't remember how loud it was. So clunk noise, black smoke immediately diminished, but now putting out BLUE
smoke and tons, 😬 I was only 2 mins from my house so I got it home, it still ran quite well, but during the cool down idle, it was putting out blue smoke like a chimney, a lot.
I am open to any speculation or suggestions on what could be wrong. This is obviously not my area of expertise, the mechanic is going to take it back after the first of the year, but I'd love to give him some ammunition to what could be the issue.
Thank you advance!
Seth
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  #2  
Old 12-24-2020, 09:17 AM
Goteborg Vapenfabrik Goteborg Vapenfabrik is offline
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Have you had all the injectors rebuilt with new Bosch nozzles? The injectors should be lapped as part of the rebuilding process.
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Old 12-24-2020, 09:22 AM
Sethsquatch Sethsquatch is offline
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Quote:
Originally Posted by Goteborg Vapenfabrik View Post
Have you had all the injectors rebuilt with new Bosch nozzles? The injectors should be lapped as part of the rebuilding process.
Yes new injectors, basically everything including head gasket up is new, glow plugs, Turbo, injector pump, injectors.... Would an injector cause it to burn oil? Also engine doesn't seem to be missing or sputtering, runs and idles good, just tons of blue smoke.
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Old 12-24-2020, 10:23 AM
ngoma ngoma is offline
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You are correct that blue smoke usually indicates burning oil. Somehow oil must be entering the combustion chamber. I can only think of piston rings, valve guides, or possibly holed piston? I suppose a damaged turbocharger could divert oil into the intake.

Very interesting your description of what happened.

Driving normally except for voluminous black smoke, then a single loud "clunk," then no more black smoke, but voluminous blue smoke?

No change in engine tone otherwise?

Same performance before/after the "clunk?"

Smooth idle?

What is the oil level?

I'd be hesitant to run the engine before a good inspection.
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  #5  
Old 12-24-2020, 10:33 AM
Sethsquatch Sethsquatch is offline
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Quote:
Originally Posted by ngoma View Post
You are correct that blue smoke usually indicates burning oil. Somehow oil must be entering the combustion chamber. I can only think of piston rings, valve guides, or possibly holed piston? I suppose a damaged turbocharger could divert oil into the intake.

Very interesting your description of what happened.

Driving normally except for voluminous black smoke, then a single loud "clunk," then no more black smoke, but voluminous blue smoke?

No change in engine tone otherwise?

Same performance before/after the "clunk?"

Smooth idle?

What is the oil level?

I'd be hesitant to run the engine before a good inspection.
Hard to get a bearing on engine performance, but little to no difference. Before the noise there was a louder clattering noise? Like a card in bike spokes.
Then the engine was noticeably quieter with much less black smoke but tons of blue. It is weird.
What is a valve guide? Excuse my ignorance.
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Old 12-24-2020, 01:08 PM
v8volvo v8volvo is offline
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As ngoma suggested, you don't want to run the engine again until careful inspection. These are weird symptoms and hard to guess the cause, but some possibilities involve the timing system and if that is involved and something is coming loose, the damage could get a lot worse.

Bluish-white smoke in some instances can be from poorly combusted fuel, it might not necessarily be oil. The fact that the sound and smoke output of the engine instantly changed after the "clunk" is a classic scenario of slipped timing, which could be a timing belt jumping a tooth, a tensioner falling out of position, crankshaft timing gear slipping / keyway rounding, etc. Timing belt tension, cam and IP timing, and CRANKSHAFT BOLT TORQUE all need to be confirmed perfect before starting it again. Then move on to other possibilities once you know the engine is not about to self-destruct.

Also maybe we should back up a minute so that we get the whole story. In another thread you were working on figuring out major difficulty with starting. After the mechanic's recent adjustments leading up to when you got the truck back this time, was that previous problem fixed? Started quickly and cleanly, no struggle or long cranking or rough idle after startup? You say runs and idles good. But is that all the time or only after it warms up?

AND, if the other problem was solved, what were the specific adjustments that were made in connection with that? Adjustments to the fuel pump itself? Timing adjustments? Can you get more exact detail from your mechanic on this? It could be that something they recently changed during that attempt is to blame for the new episode now.
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  #7  
Old 12-24-2020, 01:15 PM
Sethsquatch Sethsquatch is offline
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Quote:
Originally Posted by v8volvo View Post
As ngoma suggested, you don't want to run the engine again until careful inspection. These are weird symptoms and hard to guess the cause, but some possibilities involve the timing system and if that is involved and something is coming loose, the damage could get a lot worse.

Bluish-white smoke in some instances can be from poorly combusted fuel, it might not necessarily be oil. The fact that the sound and smoke output of the engine instantly changed after the "clunk" is a classic scenario of slipped timing, which could be a timing belt jumping a tooth, a tensioner falling out of position, crankshaft timing gear slipping / keyway rounding, etc. Timing belt tension, cam and IP timing, and CRANKSHAFT BOLT TORQUE all need to be confirmed perfect before starting it again. Then move on to other possibilities once you know the engine is not about to self-destruct.

Also maybe we should back up a minute so that we get the whole story. In another thread you were working on figuring out major difficulty with starting. After the mechanic's recent adjustments leading up to when you got the truck back this time, was that previous problem fixed? Started quickly and cleanly, no struggle or long cranking or rough idle after startup? You say runs and idles good. But is that all the time or only after it warms up?

AND, if the other problem was solved, what were the specific adjustments that were made in connection with that? Adjustments to the fuel pump itself? Timing adjustments? Can you get more exact detail from your mechanic on this? It could be that something they recently changed during that attempt is to blame for the new episode now.
Incredible response, thank you!
So previous post, someone suggested 12v glow plugs, which was definitely the majority of the issue. Timing was rechecked, and was within spec, I believe 0.85mm? Mechanic consulted with someone in UK who rebuilds Pinzgauers and walked him through adjusting fuel pump.
When I arrived to pick it up yesterday, it was just below freezing outside, and after running glows once, it fired immediately and idled with no smoke. It ran for maybe 15 mins before I drove Jr home. But did have quite a bit of black smoke driving home, which mechanic said he had dialed almost all out, so not sure why it changed when I drove it. I'm sorry I don't have more details.
Mechanic suggested maybe vacuum pump failed, and engine is sucking oil into vacuum lines? Does this seem like a possibility?
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  #8  
Old 12-24-2020, 01:25 PM
Sethsquatch Sethsquatch is offline
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That's some tough love 🤣
No not Linden engineering, this is Weissach Performance in Boulder.
Agreed on a specialist. Mike, my mechanic is incredibly honest and reliable and has worked on my vehicles for years. He isn't charging me for any rework or anything he's had to go back and fix. When I was there a few years ago, he had a Volvo C303, he's currently working on a Unimog. While neither of these is related to a Pinzgauer, he's used to working on obscure vehicles.
Mike is a good guy, coming by Saturday, the day after Christmas, on his own time to my house to troubleshoot it.
I have faith in him, just wanting to give him as much information as I can. We also had a company in the UK providing us constant consulting during the rebuild process.
Valid points nonetheless.
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  #9  
Old 12-24-2020, 01:26 PM
v8volvo v8volvo is offline
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Before I saw your reply, I was about to make a post questioning your mechanic's ability to ever get this engine running right for you given what we have heard up to now. But it does sound like he's trying, so maybe you're prepared to give him another shot.

Vacuum pump failure is theoretically possible in such a way that oil gets into the vacuum system, but remember (and remind your mechanic) the two reasons why his idea of oil being sucked into the intake from vacuum lines is impossible:

1) This is a diesel engine and therefore there is no vacuum in the intake manifold, as a gas engine would have. In fact, since it's a turbocharged engine, there is often *positive* pressure. How would oil be sucked in to get burned in the cylinders?

2) Due to #1 above, unlike a gas engine, on this engine there is also no connection between the vacuum system and the intake manifold! So, suppose the vacuum pump does implode and force oil into the vacuum system... how is that oil supposed to make its way into the intake?
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  #10  
Old 12-24-2020, 01:37 PM
v8volvo v8volvo is offline
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We're not trying to be tough on him, even tough love. But diesel and gasoline engines can be like two completely different languages. Some guys speak one, but just haven't yet made the investment of time to be functional with the other. Many of us on here who are comfortable playing around with diesels would be lost trying to deal with a complicated problem on a gas engine.

A person could even be a deeply skilled professional expert in one world, but still become a novice when trying to translate their skill to the other.

Doesn't mean they can't learn (and certainly your guy sounds like he wants to get it right).
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