Offshoreonly.com - 540 BBC running poorly

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Quote:

Originally Posted by Full Force (Post 4658511)

My gun is set up like that, it came that way and never had any issues, eventually I plan to change that, but for now it works fine that way.

Using the mechanical as a lift pump and the electric one is between the mech and carbs?

Quote:

Originally Posted by Baja Rooster (Post 4658539)

Using the mechanical as a lift pump and the electric one is between the mech and carbs?

Mine is set up with the electric pumps first, delivering fuel to the mechanicals, then on to the carbs.

I just checked with the builder again - they said total timing needs to be 35 or less, initial could be as low as 12 but depends on a variety of factors with setup. THey were surprised by me needing 22-24 degrees at idle.

Quote:

Originally Posted by ancho (Post 4658548)

if youre setting base to 24*, then how much total do you have !?
also, is the timing pointer verified that tdc is actually tdc

Quote:

Originally Posted by MILD THUNDER (Post 4658550)

if youre setting base to 24*, then how much total do you have !?
also, is the timing pointer verified that tdc is actually tdc

I'm embarrassed to admit that I don't have definitive answers to either question.
I know that I'm *close* to TDC, by observing piston position on cylinder #1 and rotor position.

https://cimg1.ibsrv.net/gimg/www.off...16946a1f43.png
are the plug wires connected as in this picture, doesn't really matter where #1 starts on the cap as long as a the rotor is pointing at it

Any chance the float in the carb is set to high or the needle is sticking and just dumping to much gas in the motor

Like MT, F2 and others are saying you gotta get your full advance confirmed. Personally I'd pull and reset your distributors with your pointer aiming at #1 on the cap when confirming at TDC. Rotate counter clockwise 15 deg plus or minus and and snug down and fire up and get your full advance to 34 deg and tighten down. Rev up to 4K even just to confirm your completely advanced. I have a feeling your distributors and or ign boxes are having some isssues.

Also F2 correct with last post. Please try a hei for a quick test. Even if it's a junkyard piece or new off eBay for 50.00. They are everywhere. I have a feeling problem will be solved and you can at least go from there. I'm curious how much advance your msd box is set up for.

I know much is repeat here but at the very least get your totsl advanced dialed in. Yes the chance of both boxs and or distributors going goofy at or near the same time isn't out of the question. Once all said and done then change your rev limiters to 5,600-5,800 and reprop. Lol.... be a new ride. :flag:

I like that plan. HEIs are good. Lots of MSDs are not.

At least it cuts to the chase right now with a 2 wire hook up. Dont here of to much trouble shooting on them. Perfect for those NA builds.