White or Blue smoke after it warms up?

[4x4Junkie13]

Just finished putting a used 6.5L N/A into my 2001 M1123. Now I have some blue smoke, maybe it is white, it is hard to tell, once the engine warms up a bit. If I take the cap off the oil filler, there is visible vapor.
Is the engine roached or is there something else that may be causing this?
The previous owner of the engine showed me a video of it running without any signs like this.

If the engine is done and I have blow-by, what is my best bet for sourcing a new engine or remanufacturing this one?
Also, I live in San Antonio TX. I would rather not ship it to another state.

 

[Mogman]

I am assuming warming up a little bit is all you have done.
Put 500-1000 miles on it before worrying too much about it.

 

[Retiredwarhorses]

Just drive it till it blows…some blow by is just fine, ive seen brand new motors with blow by till they are worn in.
blue smoke is oil…so valve guide seals generally the culprit, once hot and the seal expands, it goes away.
what the timing set at?

 

[TOBASH]

This is a super frequent topic. Lots of advice in previous posts.

Good luck to you

 

[4x4Junkie13]

Just drive it till it blows…some blow by is just fine, ive seen brand new motors with blow by till they are worn in.
blue smoke is oil…so valve guide seals generally the culprit, once hot and the seal expands, it goes away.
what the timing set at?

I literally took the guys word for it and dropped it in, hooked up the sensors and started it up. It has a few thousand miles on it and it had no smoke in the video I saw but it is blowing kinda thick now.
I have no idea what it is timed at.
I am getting a glow plug adaptor to check compression, something I should have done before dropping it in.

 

[Mogman]

I literally took the guys word for it and dropped it in, hooked up the sensors and started it up. It has a few thousand miles on it and it had no smoke in the video I saw but it is blowing kinda thick now.
I have no idea what it is timed at.
I am getting a glow plug adaptor to check compression, something I should have done before dropping it in.

Curious, did the old engine blow up? the reason I ask is your exhaust could be contaminated with oil, water or fuel.

 

[4x4Junkie13]

Curious, did the old engine blow up? the reason I ask is your exhaust could be contaminated with oil, water or fuel.

Funny you mentioned that, yes the old motor blew water and oil through the crossover, through the cat and into the muffler. When I dropped each, they were full of water and oil. GovPlanet surplus trucks are fun….lol
I thought I rinsed them out pretty good but maybe this is really where it all is coming from.

 

[4x4Junkie13]

Curious, did the old engine blow up? the reason I ask is your exhaust could be contaminated with oil, water or fuel.

Thanks, I was kind of thinking this could be it but at the same time it seemed like a lot of smoke. I’ll run it for a while and see if it burns off.

 

[Mogman]

Thanks, I was kind of thinking this could be it but at the same time it seemed like a lot of smoke. I’ll run it for a while and see if it burns off.

It can take a while to cook that stuff out, it really needs to get a load on it to heat the exhaust up or it could smoke for a long time, if nothing else run it at a higher RPM using the high idle control under the dash.

 

[AAVP7]

Another way to check the engine condition is to measure the crankcase pressure. The TMs show how to use a U-shaped manometer, but you can also just bend some clear tubing and tape it to something. Then fill it with water. The end of the tube is stuck with a cork into the oil dipstick tube.

If I remember correctly, at idle, the crankcase should have slightly lower pressure than ambient (water is drawn towards engine), and at rpm, slight overpressure (water pushed away from engine). I think the TM even gives values which you can easily compare to an inch-scale that you mark on the tubing.

 

[Mogman]

Update??

 

[4x4Junkie13]

So after running it a bit, it looks like a freeze plug is leaking.
The header looks to be wet coming out of the head at the forward end cylinders. I am going to compression test to be sure but I think the at least a few valve guides are toast on each head.
still blowing smoke after it warms up.

 

[Mogman]

It still does not sound like you have enough miles on it to pass judgment yet, It will take some time at with real load to cook out the oil and water in the exhaust, and to make sure the rings and seals have enough time to line themselves up, you are not going to build enough heat in the driveway, Unless there is some other indication of trouble (fix the water leak) put at least 100 REAL highway miles on it before doing anything as far as tearing into it.
These symptoms have been seen before as RWH has stated above, he has worked on hundreds of Humvee's
Also can you explain how you are seeing inside the exhaust manifold?

 

[4x4Junkie13]

Drove the truck a bit and the smoking stopped. Restarted it and drove it with no smoke. Let it cool off for a few hours and drove it again, after warming up again it smoked then stopped. I can only assume it is all of that oil in the exhaust system.

 

[4x4Junkie13]

It still does not sound like you have enough miles on it to pass judgment yet, It will take some time at with real load to cook out the oil and water in the exhaust, and to make sure the rings and seals have enough time to line themselves up, you are not going to build enough heat in the driveway, Unless there is some other indication of trouble (fix the water leak) put at least 100 REAL highway miles on it before doing anything as far as tearing into it.
These symptoms have been seen before as RWH has stated above, he has worked on hundreds of Humvee's
Also can you explain how you are seeing inside the exhaust manifold?

I can't see inside the header but I was seeing liquid on the outside of the runners coming down from the flange and head. Turns out I had a bad clamp on the fuel line there and it was being blown up on to the header.