Hibernation casualty

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dstrausb1
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Hibernation casualty

Post by dstrausb1 »

Hello fellow M37ers.
I started my M37 Sunday after its winter hibernation and bad things happened.
Clouds of white smoke and engine oil dripping from the exhaust.
I didn’t notice significant missing, like the problem was localized to just one cylinder, but I might have missed that.
Can anyone suggest what might have broken or how to further diagnose the problem?
Is there any hope that the fix could be something less than a full engine rebuild?
Thanks,
Dan
Thanks,
Dan
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w30bob
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Re: Hibernation casualty

Post by w30bob »

Hi Dan,

Hmmmmmm.......that doesn't sound good. White smoke is associated with coolant (antifreeze), blue smoke with oil. Liquid oil coming out the exhaust pipe??? How about some more info.....

What color is the oil on the dipstick?
What's the level on the dipstick?
What color is the antifreeze in the radiator?
What's the level of antifreeze in the radiator?

You can see I'm leaning toward a blown head gasket........but let's not jump the gun. It's important you don't run it if there's antifreeze in the oil pan......it makes for a terrible lubricant. :mrgreen:

regards,
bob
dstrausb1
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Re: Hibernation casualty

Post by dstrausb1 »

Hi Bob, thanks for the reply.
The level water level in the radiator looks about where it usually is.
The antifreeze color is green.
The oil on the dipstick is black and clear, not chocolate milky looking as I’ve seen with water in the oil.
The oil level is high, almost as far above the full mark as the add mark is below it.
The oil seems to be too thin in my opinion and I believe I can smell gas in the oil too.
Now, the rest of the story:
I had what I thought were carb problems, running rich and blowing black smoke, last fall.
I swapped in a rebuilt carb but no improvement (stupid, expensive, unsuccessful move, still beating myself up over that one).
In the end the plugs became so carboned up that they were shorting and not sparking across the gap. I pulled the plugs, coil, and condenser and over the winter cleaned them and confirmed that each gave a good spark with the coil and condenser from the engine.
This spring, having an ahHA moment about bad gas, I’d rigged up a gravity supply to the carb with fresh gas.
And the engine did start and run, without black smoke but with the symptoms first reported.
The fuel pump was directed to a can on the ground while the engine was running.
I did not check the oil last fall; it could have been normal or could have been thin and gassy smelling as I believe it is now.
Don’t know how gas in the oil can lead to white smoke (I don’t think it was blue but I didn’t really consider color when I was looking at it, beyond noting it wasn’t black like last fall) (and not just a bit of smoke, billowing clouds that had the neighbors looking and the wife yelling at me, again) and oil dripping from the exhaust (probably a tablespoonful in the three or four minutes I ran the engine).
Does any of the above lead us closer to an explanation or at least suggest next area of investigation (fuel pump?)?
Thanks for any/all help.
Thanks,
Dan
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w30bob
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Re: Hibernation casualty

Post by w30bob »

Hi Dan,

Thanks for the info. I don't want to lead you down the wrong path, as there are guys on here with much more experience with the 230 Dodge than me, so I'm hopin they join in. But the first thing I'd do is get that oil out of the crankcase! If the oil is diluted with fuel it's not a big deal as long as you don't run it that way. If it's diluted with coolant you're going to get rust on things you don't want rust on. So drain the oil and try to determine what it's mixed with. The oil out the exhaust has me scratching my head. :D

regards,
bob
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w30bob
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Re: Hibernation casualty

Post by w30bob »

Hi Dan,

I've been thinking (never a good thing) about your situation. Now that I read your second post about the spark plug issue it's starting to make a little sense. You've got fuel in your oil from all the fuel not burned by the bad plugs and getting past the rings. The oil in your exhaust is probably not liquid oil, like in the crankcase, but the result of carbon in your exhaust mixing with water vapor. There's really no way oil from the crankcase can make it to the end of the tailpipe without being burned at some point and making lots of blue smoke......so I'm going with carbon and water that mixes and looks like oil. The white smoke is raw fuel being vaporized in the exhaust. You're wife was smart in making you shut it off, as this stuff is very flammable. How it got there is another question, but I'd say the overfilled crankcase may be letting the PCV valve suck fuel vapors from the crankcase and dump them into the intake. I think that's where the PCV attaches.

So if it were me, I'd drain the oil, refill, and fire it up. If the white smoke continues for more than a few minutes you've got other problems. Smell the smoke. Yeah, your neighbors will think you're nuts.....but if it smells sweet it's antifreeze. If not don't light a cigarette. Light gray smoke is fuel, billowing white smoke is coolant being burned. I think what you find will point you in the right direction if there is still a problem.

One more thing....and others will probably tell you I'm nuts..........but if the problem is gone I'd drain the oil AGAIN and change the filter after you run it a bit just to make sure you got all the water out of there. Some will say if you drive it and get it good and hot the water will burn off.....and that's probably true. But if it were me I'd do both....drain it again and go for a long drive.

Let us know how you make out.

regards,
bob
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pwrwagonfire
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Re: Hibernation casualty

Post by pwrwagonfire »

w30bob wrote:Hi Dan,

I've been thinking (never a good thing) about your situation. Now that I read your second post about the spark plug issue it's starting to make a little sense. You've got fuel in your oil from all the fuel not burned by the bad plugs and getting past the rings. The oil in your exhaust is probably not liquid oil, like in the crankcase, but the result of carbon in your exhaust mixing with water vapor. There's really no way oil from the crankcase can make it to the end of the tailpipe without being burned at some point and making lots of blue smoke......so I'm going with carbon and water that mixes and looks like oil. The white smoke is raw fuel being vaporized in the exhaust. You're wife was smart in making you shut it off, as this stuff is very flammable. How it got there is another question, but I'd say the overfilled crankcase may be letting the PCV valve suck fuel vapors from the crankcase and dump them into the intake. I think that's where the PCV attaches.

So if it were me, I'd drain the oil, refill, and fire it up. If the white smoke continues for more than a few minutes you've got other problems. Smell the smoke. Yeah, your neighbors will think you're nuts.....but if it smells sweet it's antifreeze. If not don't light a cigarette. Light gray smoke is fuel, billowing white smoke is coolant being burned. I think what you find will point you in the right direction if there is still a problem.

One more thing....and others will probably tell you I'm nuts..........but if the problem is gone I'd drain the oil AGAIN and change the filter after you run it a bit just to make sure you got all the water out of there. Some will say if you drive it and get it good and hot the water will burn off.....and that's probably true. But if it were me I'd do both....drain it again and go for a long drive.

Let us know how you make out.

regards,
bob

this is my guess! My truck had gas in the oil when I got it...was bad rings
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Re: Hibernation casualty

Post by rtkjmk »

Don't forget to check your fuel pump , bad pump will fill your crankcase with fuel fast .
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Re: Hibernation casualty

Post by 8543bob »

GOOD MORNING,
I would do a compression ck before I went any further; other than putting in new oil and filter. It tells a lot about the engine internals.
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Re: Hibernation casualty

Post by JimC »

Sounds kind of like a bad diaphragm in the fuel pump letting gas into the block, but a broken ring can have the same effect..

The white 'smoke' is steam from water in the coolant. Sounds like it may be a blown head gasket as Bob suggested.

Also looks like we've got a Troll on the site attacking Bob.
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Re: Hibernation casualty

Post by refit1701 »

The black stuff out the exhaust could just be condensation in the muffler or pipes mixing with carbon. I would definitely check the fuel pump for a bad diaphragm.
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Re: Hibernation casualty

Post by Tuko »

I've seen some random posts but that one is #1 in my book :mrgreen:
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Re: Hibernation casualty

Post by m37jarhead »

8543bob wrote:GOOD MORNING,
I would do a compression ck before I went any further; other than putting in new oil and filter. It tells a lot about the engine internals.
Yep... I agree with 8543Bob, do a compression test and report your findings.
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dstrausb1
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Re: Hibernation casualty

Post by dstrausb1 »

Many thanks to all who offered words of wisdom and of hope.
It was the fuel pump. My approach always seems to be to work on the most expensive part first, the carburetor in this instance.
Feel kind of stupid, it seems so obvious in hindsight that a simple sniff of the oil would have been in order.
That's fixed, now I'm trying to remove the exhaust manifold, it's cracked. At least I can be confident that I'm working on the right part this time.
Thanks again Board, your support is the only thing that keeps me going sometimes.
Thanks,
Dan
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Re: Hibernation casualty

Post by w30bob »

Dan,

Don't for an instant think you got the market covered when it comes to stupidity. I could send you a list of dumb things I've done over the years that'll keep you laughing for a good long time. :D

regards,
bob
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Re: Hibernation casualty

Post by m37jarhead »

Glad you found the problem in the fuel pump.
Did it also cure the "white" smoke? Most agreed white smoke
would come from water leaks, i.e. bad head gasket or cracked block or
cracked head.
Just askin'
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