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Old 07-04-2007, 09:58 PM   #1
Lated
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Burning oil

My truck is burning oil in the number three cylinder. There is a large cloud of bluish smoke when I start the truck and also if I accelerate hard. My question is this, how can I tell if the oil is getting into the cylinder past a piston ring or dripping past a valve seal. It seems to me that if it was a ring then it wouldn't make a big cloud when it starts because oil doesn't flow up but it could drip down past a leaking valve seal. I'm hoping it's just a valve seal that I can fix when I do my carb and intake manifold swap.
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Old 07-04-2007, 10:02 PM   #2
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Re: Burning oil

GENERALLY smoke at startup is an indication of oil coming in at the valve as you note. The valve seal is a band-aid for worn guides but may help somewhat.

How can you be sure that it's only #3?
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Old 07-04-2007, 10:06 PM   #3
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Re: Burning oil

I guess I shouldn't say only #3 but I pulled all the plugs and #3 is black and sooty but the rest of them are at least cleaner than it is so #3 is the big problem right now.
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Old 07-04-2007, 10:15 PM   #4
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Re: Burning oil

I think you're right and that's a pretty good indication.

IMHO...I'd leave it. It's a fair bit of work to change all the valve seals as I'm sure you know, and unless you're killing mosquitos in 3 counties it's not likely to help a whole bunch
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Old 07-04-2007, 10:33 PM   #5
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Re: Burning oil

Best way to tell if it is the seals is to run up tp speed and let off. If it emits a cloud of smoke when you step down on it again the guides are worn or seals are bad or both. Sounds like you have oil ring problems also if it smokes wnen you are pulling hard.
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Old 07-05-2007, 12:05 AM   #6
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Re: Burning oil

If it smokes on acceleration its the rings, on decel its the valve guides as a general rule.
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Old 07-05-2007, 12:29 AM   #7
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Re: Burning oil

Mine does that. Number 4 and 6 on the 454 are getting carboned up from the oil burning on it. Mine normally does it during higher rpms to get that gummed up. Mine does it after I drive it and come back out like from the store and start it up. When I get on it I get a cloud of smoke from that side. I haven't yet seen if it does it when I let off....Mikey
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Old 07-05-2007, 08:09 AM   #8
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Re: Burning oil

I would do a quick compression test on the cylinder. If rings are worn, the compression will be significantly lower in that cylinder. You can buy a "no fowl" spark plug extension to buy you some time. It is just ahollow thingy that you screw into the head and then screw the plug into it. It helps minimize the plug from fouling but like all the other suggestions---it is just a bandaid. Good luck
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