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SWGA Boater
05-12-2013, 09:24 PM
I bought a new to my family 91 Prostar this weekend to play with while I am working on a S&S rebuild. Boat ran fine and really strong out of the hole during the test run yesterday. I also let it idle in the yard this afternoon before taking it to the river. Engine ran fine at the loading ramp for 3-4 minutes and then shut off and I haven't been able to get it to crank back up since. Was idling fine, stumbled and died.

Plug wires/cap look recent, coil is older. I checked and there is spark from coil to cap. Fuel is being delivered when using the throttle or manually so the front bowl of the carb is full...leads you to believe fuel pump is working. If pump was bad I would think bowl would have ran dry. I can get the engine to stumble by feathering it with starting fluid.

Being that the engine ran fine yesterday, and idled today, I am thinking timing would be OK. I have the carb off the S&S that I could put on it, but I'm not sure if it needs going through because it has been awhile since it was ran.

Any thoughts on what to try first? Tear down carb?

Thanks,

Ansley

east tx skier
05-12-2013, 09:47 PM
Have you ruled out the safety lanyard/kill switch. Remove tether, push the button in, and turn the key. If it runs, that's your problem. Bypass it until a new one arrives. They die a slow death. So that would explain its running fine the day before.

SWGA Boater
05-12-2013, 10:07 PM
Thanks ETS, I check the kill switch tomorrow afterwork.

SWGA Boater
05-13-2013, 09:27 AM
I do not think the kill switch is connected. I do not see it near the shifter. Also, should there be any beeping, etc when turning the key on. There is none, but I was curious after reading a few other threads.

SWGA Boater
05-13-2013, 03:42 PM
Still no luck. I took the fuel hose from the carb just to see that it was still pumping fuel. Output seems OK. Think it is time to go through the carb?

east tx skier
05-14-2013, 11:19 AM
I might be mistaken, but I recall on the 91 I have seen that the safety lanyard attachment point is on the dash (left side).

thatsmrmastercraft
05-14-2013, 11:35 AM
I bought a new to my family 91 Prostar this weekend to play with while I am working on a S&S rebuild. Boat ran fine and really strong out of the hole during the test run yesterday. I also let it idle in the yard this afternoon before taking it to the river. Engine ran fine at the loading ramp for 3-4 minutes and then shut off and I haven't been able to get it to crank back up since. Was idling fine, stumbled and died.

Plug wires/cap look recent, coil is older. I checked and there is spark from coil to cap. Fuel is being delivered when using the throttle or manually so the front bowl of the carb is full...leads you to believe fuel pump is working. If pump was bad I would think bowl would have ran dry. I can get the engine to stumble by feathering it with starting fluid.

Being that the engine ran fine yesterday, and idled today, I am thinking timing would be OK. I have the carb off the S&S that I could put on it, but I'm not sure if it needs going through because it has been awhile since it was ran.

Any thoughts on what to try first? Tear down carb?

Thanks,

Ansley

I think you need to verify that spark is getting to the spark plugs. If you have fuel in the carb, it should at least run somewhat so I wouldn't jump into the carb just yet.

SWGA Boater
05-14-2013, 12:45 PM
Agree. My dad is bringing a timing light over today to check fire to plugs. Distributor still has points so we will check it out also.

SWGA Boater
05-16-2013, 09:20 PM
Got the engine to run/stumble tonight. Time for a carb rebuild. It is really funny how it was running fine, and slowly died. Think something is going on in the front bowl. Also with the throttle disconnected, and pumping the accelerator, you can hear air sucking from the accelerator pump. Also no fine mist of gas is being pump only larger droplets for lack of a better word. I ordered a carb kit earlier in the week just in case and it came in today. Hope to be able to get out on the water this weekend.

thatsmrmastercraft
05-17-2013, 02:16 AM
Got the engine to run/stumble tonight. Time for a carb rebuild. It is really funny how it was running fine, and slowly died. Think something is going on in the front bowl. Also with the throttle disconnected, and pumping the accelerator, you can hear air sucking from the accelerator pump. Also no fine mist of gas is being pump only larger droplets for lack of a better word. I ordered a carb kit earlier in the week just in case and it came in today. Hope to be able to get out on the water this weekend.

Make sure to let it soak long enough to get the passages clean. That is usually the downfall of carb rebuilding. Good luck.

SWGA Boater
05-18-2013, 04:33 PM
With the carb broken down i could see water in the gas. Possibly contributing to the problem. Prior to trying to run the boat last weekend i filled up the tank. Would you try and run the tank gas out after the carb rebuild? Would installing a fuel water separator help in this situation? Or should i just bite the bullet and pump out the tank?

Thanks,

Ansley

SWGA Boater
05-23-2013, 07:25 PM
Got my carb rebuilt, water/fuel separator has arrived. All new fuel hose, vent, and fill hose should arrive tomorrow. Siphoned out fuel in the tank, then removed tank for a clean and pressure wash. Putting it all back together tomorrow. Fingers crossed, I hope to get on the water this weekend.

mikeg205
05-23-2013, 07:53 PM
Got my carb rebuilt, water/fuel separator has arrived. All new fuel hose, vent, and fill hose should arrive tomorrow. Siphoned out fuel in the tank, then removed tank for a clean and pressure wash. Putting it all back together tomorrow. Fingers crossed, I hope to get on the water this weekend.

Good luck...

SWGA Boater
05-24-2013, 08:48 PM
So i got my new water separator, but am having trouble trying to mount it. Bilge height is too short to mount upright. Bracket holes are above the stringer height. Any suggestions? Fabricate a bracket?

Thanks!

Ansley