Reproduction Parts for 1916-1964 Chevrolet Passenger Cars & 1918-1987 Chevrolet & GMC Trucks



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#150735 08/26/09 07:55 AM
Joined: Jan 2009
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Shade Tree Mechanic
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Shade Tree Mechanic
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droolCan anyone tell me what are "floating the valves"and can this bend the push rods in my '29

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Backyard Mechanic
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I would guess if your bending push rods you have sticky valves stems, usually caused from old gas forming varnish.
Extremely high RPM's can cause floating of the valves. Not likely to happen with a stock six cylinder Chevy. You might want to check your valve springs for proper tension.
Cleon

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My understanding of that is that you are calling for too many rpm that the eng cannot produce. At more rpm than the valve train can produce, valve springs not strong enough to close valves completely and rest of valve train trying to push the valves open, you have a condition of valves somewhere between open and closed, thus "floating". Not a good thing to do.
On hydraulic lifter cars, the valves will float quicker than solid lifter cars due to hydraulic action giving up quicker.
Easy to hear as when max rpm is reached, eng will start to stutter and miss.

Jim.

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Shade Tree Mechanic
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Shade Tree Mechanic
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talk Thanks Guys...I was asking because I have a new noise and cannot figure what it is.I havent looked at the push rods yet even though their new. Seems my 29 when accelerating quickly stutters and losses power. Can not get it to go more than 30 mph.I had my carb rebuilt by Chipper but still have same problem.

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Oil Can Mechanic
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Sounds like it is too lean. Have you tried adjusting the carb?


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A friend of mine had the exact same problem on his 1931 roadster. Found out that he had a defective head gasket. We replaced the head gasket and the car ran like a dream and it had plenty of power too.

laugh wink beer2


The Mangy Old Mutt

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Have you checked the distributor to make sure that the "automatic advance" is working right?

What is the sound? Have you done a compression check recently?


How Sweet the roar of a Chevy four!
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Oil Can Mechanic
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and then there's a chance Mickey and Minnie have set up house keeping in the exhaust system


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