Run on, on, on

My 4.3 Vortec (carb) runs on sometimes. Would switching to colder plugs make any difference?

Timing is everything ....

I have a complete FI intake from a 4.3 from a 2002 Chevy pickup. Pay for shipping and it's yours.

I found that the mercrusier I had tended to run on a bit, but the mechanic told me to go to the higher octane fuel and it didn,t do it again.We have to types of octane in New Zealand 91 and 96
Hope that helps might be a cheap way to solve the problem

mike...
what all does it take to switch to FI from carb? I may be interested!

all the mercruiser carb engines have the same problem with run on. When you come down off plane you need to let it idle a few minutes before shutting it down. The bowl in the carb gets full when you let the throttle down but the engine is still turning RPM's while you slow (mechanical fuel pump). Really a pain in the butt, but if you always let it idle down it will be fine.

Mat;
I have a Volvo Penta SX with a holly carb. I'll try the idle down but I'm not hopeful. We have to idle in to the dock so the engine's been at low rpms for a couple of minutes before shut off. .... Although my son loves to give it a big shot of gas in reverse to stop the boat ... so maybe you're right after all. I'll give it a try and let you know.

Mike: I've always wanted to go EFI but I thibk it's more complicated than bolting on a manifold (other parts are required right?)

Wakecord; I should check the timing anyway. The motor is 4 years old and I don't think anyone has checked it.

Maryin;
In the great white north we have a single gas pimp on the lake. He charges a $$$ for gas and there is only one flavour. I'll try bring in a couple of cans of gas but I can't do that long term.

Thanks guys

Gordon, you are right about that last post on parts:
To just do TBI (throttle body injection):
New computer, intake, throttle body, injectors, fuel pump.

Holley had a kit for about $1000, Overtons and others used to sell them, no longer do. That might tell you something.

On the timing, don't forget to advance for altitude. I think the formula is 1 degree per 2 thousand feet. Perhaps a marine tech can confirm.
Good luck.

tiMING, TIming.
too much advance by a little

Jegs still has the Holley "Pro-Jection" kits for about $840.

http://www.jegs.com/cgi-bin/ncommerce3/ProductDisplay?prrfnbr=112599&prmenbr=361

HTH

PIMF: On review, the kits are for V8s. Maybe Holley could tell you if the 4.3L (basically a 350 V8 with 2 less cylinders) is a candidate.

(Message edited by wakecord on July 28, 2004)

(Message edited by wakecord on July 28, 2004)

Has anyone installed a Holley Pro-jection system?

Was it worth it?

Holley Pro-jection SUCKS! I have one so I do know a little about it.

The only way the fuel can detonate to continue to run after the ignition is shut down is if there is carbon in the engine. This a problem that GM has been plagued with. Decarbonize the motor, do take a look at timing, and also make sure you have the right plugs in the motor. Use nothing but A/C Delco plugs, they even make a sweet marine plug.

The complete FI system that Mike is talking about would need modifications to function well on a boat, including prom programming, but would be a definite improvement. It would be a ton of work though.

If anyone ever does want to swap out for fuel injection call Howell and see what they have to offer.