350 magnum loading up
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help i have twin 350 mag carb when i start the portside motor it feels like its running on six cylinders.after running for about ten minutes at 2000 rpm which it won't exceed any way it smooths out and get up to 4800 rpm like it was bran new.if i shut it down for a half hour no problem but over that it goes back to the original problem. i disconnected the choke no diffrence. could it be a valve in the head ?its a quadrajet
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Did you try swapping the carbs side to side? Did you buy these carbs from me? One thing to look at is the little vacuum canister on the side of the carb. Make sure it is actuating when the engine starts. This canister does two things, holds the choke open a predetermined amount to make the engine run good cold, and holds closed the secondary air valve. Other than that, sounds like the float is hanging up or possibly the secondary metering rods are not seating correctly. I'd check out the vacuum canitster though. Sometimes when the rubber vacuum hose or diaphram warm up they will start working.
BT
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I had a problem similar to this last year in my small block powered 28 cigarette. It ended up being a hole in my exhaust manifold (Gil) and was trickling water into the #8 cylinder until I got to a high enough rpm to blow it out then it would clear up. But yours doesn't sound like that, just check your oil for water and maybe pull the plugs and see what they look like.
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hi bt yes i bought them from you but they are on my other boat and run fine.iwas going to switch but i wanted to eliminate other problems if there are.i might do what dave said after i do a compresion check.
thanks guys
thanks guys
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Originally Posted by sonic28
hi bt yes i bought them from you but they are on my other boat and run fine.iwas going to switch but i wanted to eliminate other problems if there are.i might do what dave said after i do a compresion check.
thanks guys
thanks guys
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Originally Posted by sonic28
there is fuel in the oil!!!!!!!!!! whats that mean?