Holley jets.....how many ## increase at a time
09-09-2007, 08:37 PM
#23
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Plug reading is extremely difficult with todays chitty fuels, it is a crap shoot to go off the plugs alone. As for the deiseling when you shut it off, I would check the float level and mabey lower it just a hair. A high float causes the motor to sputter. Just my 2 cents.
09-10-2007, 07:24 AM
#24
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You say your total advance is only 22 btdc? Too little advance is just as bad as too much. It will cause very high exhaust valve temps. Maybe that's the cause of the dieseling. Try to get the ignition to advance properly. OEM settings are conservative. I'd set the total advance closer to 30 if it were my boat, but that's just me.
09-10-2007, 07:54 AM
#25
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small block, I would stay at 28btdc. also maybe you are shutting it down too soon after you pull back the throttle. If you don't let the engine settle down you will be much more prone to run on.
09-10-2007, 07:12 PM
#26
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It is Vortex motor so the total advance is 28BTDC, so true it is slightly retarded. I am not disputing anyone and obviously open for suggestions but would too late ignition not fire early enough to burn all the fuel and cause it to act "rich".? All that being said the timing is dead nuts right at 3000RPM where I am doing my plug reading, so isn't far to say that is not a factor? From research I have done I am convinced myself the diesel after shut down is OK, i I let it idle for like 15-20 seconds shuts off normal, so I think that is just because of my quick shut down hurry up to read plugs.
