Smoke issues

67Monaco

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So to set the stage, the Monaco has the factory original engine, and it's never been cracked open out side of the timing chain and oil pan off to clean the pickup screen.

Now haven't been driving it a whole lot as there's bare metal on the body again, body work and all.

Anywho, I noticed recently that it's smoking at start up off the right bank. Since about May it's smoked like I'm fogging the neighborhood the couple of times I've had it out to the driveway. Twice I've let it run to see what happened. Both times after it got warm the smoking stopped. Valve guides or seals. My thought anyway.

However, today I took it to the gas station to fuel up as it's been getting low. Didn't smoke too much at idle, but it did start smoking about a block from the house. Every time I tried to accelerate it would smoke. Let off the pedal and the smoke went away. Coming out of the gas station about a mile away still smoked on acceleration. But less and less. Took it on a five mile ride and temps came up to normal about half way through the trip. Smoking stopped.

Pulled over got out and both pipes were clear at idle. Since I was alone I didn't have anyone to hit the throttle. Jumped on it real hard a few time on the way home and nothing, not even a puff (watching over my shoulder and the mirror).

I haven't broken out the tools yet but trying to see what the peanut gallery thinks.

Guides or Rings?
 

Davea Lux

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Loose valve guides or bad seals are probably part of the problem. Oil smoke on start up is usually a good indication of worn guides and seals. Before tearing the engine completely apart, You can replace the valve seals without removing the heads if you are good with tools. There is an air chuck that can be screwed into the spark plug hole to hold the valves closed while the springs on that cylinder are removed and the seals are replaced. You will need a shop grade air compressor at least 3hp. Remove the valve covers and rocker shafts to expose the valve springs. Install a valve spring compressor to remove the valve keepers and springs on the cylinder with the air chuck installed. The valve seals can now be removed and replaced. Be sure to plug all oil drain hoses from the heads so that you do not lose any valve keepers into the valley.
If both the oil seals and valve guides are shot, the above procedure will probably buy some time and slow the oil consumption down but not entirely fix the problem. If this is a high mileage engine, you can pull the heads and have a valve job done and install bronze guide inserts. That will cure that part of the problem, but if the engine is a well worn unit, you will probably be farther ahead to just bit the bullet and have it rebuilt.

Dave
 

savoy64

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almost always bad valve seals-----the debris you cleaned out of the oil pick up was the seals.....it will be the cheapest repair too.....
 

70NEWYORKER

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Smoke under a load can be from weak rings. Not much vacuum under a load to suck oil around valve stems. Smoke on decell can be from worn valve guides/seals
 

jcslocum

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Not running often can make these issues hard to diagnose. I think it's seals on the valve stem myself but who knows!! It could be smoking on accel, tho you can't see it with all of the air blowing around the car. You can have someone follow you to look at the pipes as you accelerate to see what smoke might be there.

Good luck with this!!
 

67Monaco

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Not running often can make these issues hard to diagnose. I think it's seals on the valve stem myself but who knows!! It could be smoking on accel, tho you can't see it with all of the air blowing around the car. You can have someone follow you to look at the pipes as you accelerate to see what smoke might be there.

Good luck with this!!


Before it fully warms up you can clearly see it smoke on acceleration.
 

traintech55

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How about we ask the $64,000.00 question. What color is the smoke?
Black, excessive fuel.
White, coolant.
Blue / gray, oil.
 

67Monaco

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Oddly, went out today, no smoke, anytime. But yesterday was enough of a drive to get it nice and warm and clear out the cylinders.

I'm starting to think valve seal. I'm thinking it's caused by the short run to get in and out of the garage is putting enough oil in the head to flow over the top of the guide(s). The resulting smoke is simply what's being burned at the next startup/run after it's had time to flow past the guide.
 

mopar440

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Probably a little valve seal, but id lean twards stuck rings, since it cdme on fast. Maybe do the old seafoam in the intake ( wayrr works as good). And steam it out, if done right, cant hurt
 
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