Smokey cold start? Help ID the issue. (1 Viewer)

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Hi there,
I’m in the market for a 100 Series and found one I liked. The owner has been very forthright so far about the condition and history of the vehicle. In a video he sent me of a cold start, it appears there is smoke coming from the exhaust.
In a service receipt from 2020, I see that a shop noted the engine was burning oil. I do not think this was addressed.
Would love some input on what is causing this and how much of an issue you all think this presents. I have a PPI scheduled for tomorrow am.
Attached is a video of said smoke.
Thanks!

[file not found]
 
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See if it will pass smog inspection. Have a compression test done.

If that is a cold start on a cold day it does not look too bad at all.

You should see my 1981 BJ44 diesel put out a smoke screen when cold.
 
If it will pass your local inspection, I wouldn't worry. You should see mine. It has 450k on it and will put out that much and more for several minutes till the engine warms up. Mine is oil getting past the rings, valve stem seals and valve guides till the engine warms up and parts expand to cut it way back. At some point I'll address it, but it's running fine otherwise and passes my state inspection.
 
If that was cold start, then it’s normal.
 
Change the PCV valve. Be careful of the gasket - if it is dry and crusty, and bits of it drop in the valve cover, you will have to pull the valve cover on that side to get it them out. They won't fall into the camshaft area, just into a little oil splash baffle in the top of the cover.
 
"shop noted the engine was burning oil." This could be wrong. But it does warrant a deeper than normal PPI.

Here's what I do and recommend.
Study history. Look closely for OF&L and Air filter intervals. Also if stater replaced. CLUES!
Look in history and Ask seller if: HM (High mileage) oil ever used to his knowledge?
Look very close at all point with rubber seal, that could leak oil. If all leaking, likely HM used.

This is the deeper than normal: Do a compression test on all 8. Then wet and leak down in any weak cylinders.
 
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Exhaust sounds mean, might need to get more info on what's been done to that motor. My exhaust pumps out a cloud for a few minutes when cold but it doesnt smell bad , no blue tint and then clears up. None of my fluids drop down so I've also summed it up to be normal. Def need to look a bit deeper into that vehicles history.
 
"shop noted the engine was burning oil." This could be wrong. But it does warrant a deeper than normal PPI.

Here's what I do and recommend.
Study history. Look closely for OF&L and Air filter intervals. Also if stater replaced. CLUES!
Look in history and Ask seller if: HM (High mileage) oil ever used to his knowledge?
Look very close at all point with rubber seal, that could leak oil. If all leaking, likely HM used.

This is the deeper than normal: Do a compression test on all 8. Then wet and leak down in any weak cylinders.
The starter was replaced 5k miles ago! Fill me in on how that is relevant. Trying to learn.
 
These trucks are starting to get a little long in the tooth, and as such little things like this will become more normal. It appears to me that it was a true cold start as it took so long for the steam to appear out of the tail pipe. When he gunned it you see a little of the residual smoke mixed with it, but it's very little. My bet is that the valve guide seals are starting to seep ever so slightly, which is not a big deal. When the engine is shut down the heads have oil pooled in them, and the lower valves are likely under the 'water line' as it were. So these seals can seep ever so slightly, letting oil into the combustion chamber, and so during startup you will get a puff of blue smoke. When they start to get really bad you will also notice that when you accelerate after letting off the gas (this is more prominent in manual cars) you will get a big puff too. This is from the increased vacuum on decel pulling in some oil past the seals. It's more of an annoyance than anything. That engine sounds good to me, if not a bit noisy in the exhaust department. I'm guessing they removed the giant silencer and put in a Magaflow or something. That's similar to what I did, but I used a Thrush Hush so it wouldn't be too noisy.
 
Mine does this, maybe not quite as bad, on a cold start. It smells very rich when I first fire it up as well. 198k miles
 
The starter was replaced 5k miles ago! Fill me in on how that is relevant. Trying to learn.
Because the intake manifold has to be removed to replace the starter, which opens up the very real possibility that junk falls inside the engine.
 
I'd be more concerned that he thinks it's alright to free rev a cold engine. This alone would probably make me walk away.
True.

Let it idle up to warm while watching. My bet is you see no smoke.
 
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These trucks are starting to get a little long in the tooth, and as such little things like this will become more normal. ..............My bet is that the valve guide seals are starting to seep ever so slightly, which is not a big deal. When the engine is shut down the heads have oil pooled in them, and the lower valves are likely under the 'water line' as it were. So these seals can seep ever so slightly, letting oil into the combustion chamber, and so during startup you will get a puff of blue smoke. When they start to get really bad you will also notice that when you accelerate after letting off the gas (this is more prominent in manual cars) you will get a big puff too. This is from the increased vacuum on decel pulling in some oil past the seals. It's more of an annoyance than anything.,.
^^^What he said. I have driven "old cars" most of my life and this is entirely correct. My 470 does it. It goes away as the engine warms up. Since I have 450k on my 470, I give it time to warm up and I don't punch it around on the road.

For guys who don't "wrench"-
I get that a person who isn't mechanically inclined would be wary of issues with "high mileage" vehicles, but being an older guy, I can say with confidence the term "high mileage" doesn't mean what it used to. They say the old cars were made better but a Ford truck from 1965 with 100k on it would be in far worse shape than a 1995 model with 100k if driven under the same conditions. I've seen it personally and yup, I'm that old. Improvements made over time in materials have made many cars that much better and with a decent amount of attention by the owner over that time, they're probably going to be in far better shape. There will be some issues as some parts wear, seals start to fail, etc. Some maintenance comes with this territory. When I used to play in the Porsche world, I'd tell the noobs to quit whining about the wrench's hourly rate and buy a set of tools for the same money. Learn to use them and don't be held hostage to the bandits at the dealer or local garage.
 

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