Backfire and bogging at higher rpm

[jonny rotten]

Took the boat out for the first time this year.Idles fine,Low speed fine.When I got on it it backfired and bogged a bit.Pulled back on throttle and it ran fine.Never stalled.Never got to WOT.Planes off fine. Needless to say it was a short day.I don't want to start throwing parts at it but this is what I was going to do first

Cap rotor wires(plugs were done 3 weeks ago)
Adding a water separator
Changing filters again
Will check timing(boat mechanic says electronic timing never go out of timing?)
Does this sound like an ignition problem or fuel? What else should I test or do?
1990 4.3

 

[jonny rotten]

Re: Backfire and bogging at higher rpm

Also,Pretty strong gas smell.Makes me think weak spark?But that's a very uneducated guess

 

[LagunaBlue]

Re: Backfire and bogging at higher rpm

Also,Pretty strong gas smell.Makes me think weak spark?But that's a very uneducated guess

Um. Where exactly is the fuel smell originating from? Is there fuel wash in your bilge? Check all the fuel lines and connections for leaks before you start investigating ignition or spark issues. We don't want you blowing yourself up afterall!

 

[stonyloam]

Re: Backfire and bogging at higher rpm

Also,Pretty strong gas smell.Makes me think weak spark?But that's a very uneducated guess

It would not be wise to run it at all until you locate where the gas smell is coming from. Gas fume build up in the bilge is VERY dangerous.