Re: 4.3L Vortex stalls on big waves
To my knowledge, the Vortec 4.3L came on board during the last several years of OMC's run.
Originally Posted by akhinton
So my first question for you is; Is this actually an OMC stern drive system........... Or, is this Volvo Penta?
Second question is; what year model stern drive system is this?
If OMC, you will have an ESA system.... if Volvo Penta, you will not!
The ESA can play a roll in ignition sytem issues when not correctly adjusted.
As for the flyweight springs..... use extreme caution if replacing this spring (or springs) without the aid of a Distributor Machine.
As you said yourself, these springs control the amount and timing of Ignition Advance.... and this occurs once out of BASE mode/rpm.
IOW, I'd not hap-hazzardly replace these springs without double and triple checking your advance curve.
It doesn't take much (incorrect spring, for example) to throw this curve off, potentially resulting in engine damage.
If you know exactly what you are doing, this can be done "On-Engine".... but requires some additional techniques.
IMO, your engine does not require the HEI.
This will change your advancing system from Mechanical Advance (spark lead control) to EST (electronic spark timing... i.e., no mechanical advance).
If you are OK with that, then by all means give it a try.
However, trouble-shooting this system while on the water will be an entirely different ball game for you.
I'm just pointing this out to you as to better help you with a decision.
You also mentioned "wave" or "surge" when this occured.
By chance is your exhaust back flow prevention inadequate, malfunctioning, etc?
Last edited by RicardoMarine; 05-29-2011 at 09:24 AM.
Rick ... aka Ricardo..... AQ series Volvo Penta repair
28' SDN F/B w/ twin Volvo Penta 5.7L DP's
Please... no PMs!
I would prefer email .... jenery (at) aol.com