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Discussion Starter #1
Hello everyone,
I have been a long time reader but first time posting. I'm having issues with my 4BD2T in my 1995 NPR. The turbo went out and filled the exhaust with oil. I got the new turbo installed. Took the glow plugs out and turned the engine over several times thinking I would need to blow it out thinking it may have loaded up. Got it all back together and she fired right up. Sounded even better than before. She idled for about 2 mins then all the sudden ran away. Smoking like a freight train. Turning the key off didnt kill it so I had to stop up the intake. Everthing checked out ok so I decided to try again. Fired right back up and idled fine for several mins. I gave it a little throttle and that went well at first. Then all the sudden it ran away again. I had to stop up the intake again. I'm lost on this one.....any help would be greatly appreciated!
 

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How much oil did it end up sucking in initially, and is it still dropping the oil level or not? I wonder if it could have enough still loaded up through the intake and intercooler piping to idle for a bit, then it works it’s way in and goes off again. Sorry, can’t offer more than a theory.
 

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Discussion Starter #3
Best I can tell all the oil went down the exhaust and it was A LOT. There wasnt any oil residue in the intercooler tube side so I didnt think any went down in the intercooler. I havent taken off the intercooler or intake..... i may have to make sure??
I had a diesel mechanic tell me that I would have to keep doing that to let it clean itself out but that sounds sketchy to me??
Could it be something with the injection pump? Or some kind of sensor? I'm waiting on 2 temp sensors to come in from isuzu. Their wires dry rotted off.
 

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Hmm. Well, hopefully someone with more experience and knowledge than me will come along. But if I’m thinking on this right, if it ran away on oil from a bad turbo, I don’t see how there wouldn’t be any in the piping. If it went out the hot side, it would be in the exhaust, and if it leaked into the cold side from the hot side, it would still have to go into the piping and intercooler before it got into the intake. Take all that with a grain of salt.

Can you tell us if it is continuing to pull new oil since the turbo replacement? Is the level continuing to drop? That will maybe tell us if it’s burning off residual, or if it’s some other issue.

Edit: Do you have a catch can, or something like that venting into the exhaust? I wonder if a bad PCV would be pulling oil out. But it still doesn’t explain the runaway, as that would still have to get into the intake somehow to burn.
 

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Discussion Starter #5
I really appreciate you taking the time to help. The oil level is not going down now. I think I will go ahead and pull the intercooler to make sure there is no oil in it before I fire it up again.
 

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Hopefully there isn’t an issue in the block, letting oil into the cylinders. Keep us posted? I’m sure someone else will chime in.
 

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Discussion Starter #7
So the intercooler was full of oil....there was no evidence of that from removing the rubber hoses. It ALL must have ran down to the bottom of the intercooler and set there until the boost pushed it up into the engine. Got it all cleaned out and good to go.
Thx
 
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