Dieseling/Valve float whats the diffrince?
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Melting Slicks
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From: The cure for the blues is eight cylinders roaring
Dieseling/Valve float whats the diffrince?
As I said in an earlier post I was driving home and guned it at over 4000rpm or better. I said I thought it was valve float but thinking on it more it sounded like dieseling.
I know valve float is caused buy weak springs or exceding a hidrolic lifers limits what else would cause this?
Is deiseling caused by poor timing?
I know valve float is caused buy weak springs or exceding a hidrolic lifers limits what else would cause this?
Is deiseling caused by poor timing?
Race Director
Joined: Jan 2000
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From: San Jose CA
Re: Dieseling/Valve float whats the diffrince? (PrarieShark)
Dieseling is when you kill the engine, but it chooses to stay alive and chugs along for a couple more seconds. If you flipped the engine over to the electrical position, it would start back up again.
Sounds like you're suffering from valve float.
-Steve
*edit* When you changed the cam, did you upgrade the springs to match specs? If not, that's DEFINITELY your problem.
[Modified by Pacin'California, 3:09 PM 9/14/2002]
Sounds like you're suffering from valve float.
-Steve
*edit* When you changed the cam, did you upgrade the springs to match specs? If not, that's DEFINITELY your problem.
[Modified by Pacin'California, 3:09 PM 9/14/2002]
Melting Slicks
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From: TEXASTEXASTEXASTEXAS TEXASTEXASTEXASTEXAS
St. Jude Contributor
Re: Dieseling/Valve float whats the diffrince? (Pacin'California)
I think he's talking about the kind of deiseling that's also called pinging or valve rattle (it sounds like the rattling you hear in a deisel engine). I always thought valve float was a whole different thing & had to do with running the RPMs so high the springs can't keep up.
Pinging/valve rattling can indeed be caused by timing that's off, as well as a badly adjusted carb, crappy gas, & engine deposits.
JB
[Modified by JB, 5:28 PM 9/14/2002]
Pinging/valve rattling can indeed be caused by timing that's off, as well as a badly adjusted carb, crappy gas, & engine deposits.
JB
[Modified by JB, 5:28 PM 9/14/2002]
Parrothead
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From: Margaritaville Embassy
St. Jude Donor '08-'09,'13, '14
Re: Dieseling/Valve float whats the diffrince? (JB)
I think he's talking about the kind of deiseling that's also called pinging or valve rattle (it sounds like the rattling you hear in a deisel engine). I always thought valve float was a whole different thing & had to do with running the RPMs so high the springs can't keep up.
JB
JB
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Melting Slicks
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From: The cure for the blues is eight cylinders roaring
Re: Dieseling/Valve float whats the diffrince? (Markm10431)
It happened under hard accelration and only for a few second once I reached speed it stoped. Does this help discribe the problem? Could poor valve adjusment cause this?
Racer
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From: Phoenix AZ
Re: Dieseling/Valve float whats the diffrince? (PrarieShark)
It sounds to me more like pinging, not valve float. You don't really hear valve float unless the piston is hitting the valve which in that case your engine won't be running right now.
Put in a higher octane gas. If that doesn't fix the problem retard your timing. Also, run some Chevron Techron fuel injector/carb cleaner crap thru your system. Don't put it in until you have less than a 1/4 tank. That way it won't be so diluted. Get as close as you feel comfortable to empty then fill up tank. You might have to repeat that a few times to get all the carbon out of your combustion chambers.
Colin
Put in a higher octane gas. If that doesn't fix the problem retard your timing. Also, run some Chevron Techron fuel injector/carb cleaner crap thru your system. Don't put it in until you have less than a 1/4 tank. That way it won't be so diluted. Get as close as you feel comfortable to empty then fill up tank. You might have to repeat that a few times to get all the carbon out of your combustion chambers.
Colin
