Gas problem

[mjradk]

I have a 1996 Sunbird 19' I/O with a 4.3L OMC cobra. I had it tuned up and serviced at the beginning of last season, and it ran great until the last trip to pull it out of the water last fall. As I headed for the boat launch, the boat stalled repeatedly. It ran for 200 yards and then stalled. Then it ran 100 yards and then stalled. Each time it started easily but ran shorter and shorter distances until at the end, I could only get it to run enough to give it a small boost each time. Luckily, I was less than a mile from the boat launch.

I ended up winterizing it and putting it away for the season before I could fix it. I checked the filter in the carb. It was OK. The choke was opening OK.

I'm going to work on it this weekend, and I'd like to put a new gas filter on it. Can I do that without losing the prime in the gas line to the electric fuel pump, or will it lose its prime when I spin off the old filter?

Any other suggestion what the problem could be?

 

[HT32BSX115]

Re: Gas problem

I have a 1996 Sunbird 19' I/O with a 4.3L OMC cobra.......................
I ended up winterizing it and putting it away for the season before I could fix it. I checked the filter in the carb. It was OK. The choke was opening OK.

I'm going to work on it this weekend, and I'd like to put a new gas filter on it. Can I do that without losing the prime in the gas line to the electric fuel pump, or will it lose its prime when I spin off the old filter?

Any other suggestion what the problem could be?

Howdy,

Welcome aboard!


Well, it does sound like a fuel related problem. You will not know until you test the fuel system.

You should start at the fuel tank. Check the tank vent, fuel pickup screen, anti-siphon check valve, fuel filter, pump, and lines to the carb.

Since you have an electric pump, you can put a gage on the output, apply power to the pump and check for flow.
( have a fire extinguisher ready and do this out of the garage out in the open!!)

Once you know you have good pressure and/or flow, you can look to other areas like the carb and ignition..

I don't think you need to worry about losing prime.


Regards,


Rick

 

[mjradk]

Re: Gas problem

Great! Thanks for your suggestions. Since the distance I was able to go was less and less, I'm hoping it's the vent, but I won't know until I take a closer look.

 

[gkbid]

Hi mjradk,

I have a 1990 Sunbird 4.3 that's having the identical issue you described. Would you mind sharing what you found and did to resolve the problem?

 

[mjradk]

The problem turned out to be the anti-siphon valve. The wall of the rubber gas line was also swollen. The local marine engine mechanic said it was because of the ethanol in the gas .... that it degrades rubber over time. In any case, a new anti-siphon valve and new rubber fuel line solved the problem. It has run great since then. Good luck!

 

[gkbid]

Thanks so much!