Hey everybody so I went to puddingstone yesterday and re-set the timing under load, the boat still has a stutter from 3k-5k if I pump the throttle it'll stay going if I stab it once it'll die, too much fuel? Not enough?

The boat is a 1970 SleekCraft 19' with a
BBC 396 .30 over with a steel crank, forged pistons, heads are 206 casting oval port closed chamber, mild cam, 1.7 full roller rockers, intake is a Victor Jr topped with a stock jetted 750 double pumper. If anyone wants to help ill supply beer! I'm in Lakewood/Long Beach area. 
Thanks in advance -Chris


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12 initial / 36 total.


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This is a new problem or a continuing dilemma?  Did this just happen since you changed the timing?  Nothing else was changed besides the timing?

Do you have to continuously pump the throttle to keep the engine in the 3k-5k range?  If so, the engine is running off of the accelerator pump and not the main circuit.

At the moment, it sounds like a fuel problem.  Is the fuel good?  Is the fuel filter restricted?  I had a similar problem when a chunk of bowl gasket clogged a jet.

This is a new problem or a continuing dilemma?  Did this just happen since you changed the timing?  Nothing else was changed besides the timing?

Do you have to continuously pump the throttle to keep the engine in the 3k-5k range?  If so, the engine is running off of the accelerator pump and not the main circuit.

At the moment, it sounds like a fuel problem.  Is the fuel good?  Is the fuel filter restricted?  I had a similar problem when a chunk of bowl gasket clogged a jet.

The fuel is fresh and I haven't checked the fuel filters I have two inline between tanks and fuel pump, it has stock jetting which I think is 78/70


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Is your throttle linkage progressive or 1:1?  Progressive means that the primaries open before secondaries.

Square up the jets in the secondaries to make sure that you have enough fuel to start.  I want to say that those carbs originally were jetted 72s or maybe 76s, my memory is fading lately.  I also think that 36 degrees total advance is too much to start with.  I would back it down to maybe 28-30 degrees total, and then give it more if it responds well once you get your fuel worked out.

Mine is progressive and I believe stock is 76/70 I threw the 78's because I already figured it was going to need more, I was using it as a baseline, I think something is definitely clogged or amiss because it never had this issue before, same fuel pump / filters / lines , also I bought the carb used as most of us do and the guy before had it set up with PV block offs and 98 mains 90 secondaries not sure what this would equate to by removing the PV


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I said the 98/90's backwards my bad


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Put a 6.5 pv in it and 71's in the front with 31 squirters. The set up your describing right now is too lean. Have you pulled a plug ?


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yeah and they looked alittle light.


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Call c&j engineering in Santa Fe springs. Take the carb to them and tell them what's happen in and you motor specs. They will dial you in.


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