350 Crusaders lose power after motors run for 10-15 minutes

[patswil]

1985 34' Silverton, twin Crusader 350/270. No water in tanks, The the vents are clear. anti siphon valves eliminated as part of problem, replaced both coils, all 3 filters(water seperators twice). POwers up when cold, runs solid for about 10-15 minutes. Motors will fire up again right after crapping out, but anemic at best, idle speed only, Motors won't perform under any sort of load after the initial stall, they stall if any load put on them. ALso both fuel pumps replaced last summer, ethanol had ruiined the diaphrams

Motors either are not getting fuel or air, but why. can't use the boat, It's been almost 1 1/2 years now.


Please help me

 

[mkast]

Re: 350 Crusaders lose power after motors run for 10-15 minutes

http://forums.iboats.com/showthread.php?t=295070

 

[patswil]

Re: 350 Crusaders lose power after motors run for 10-15 minutes

http://forums.iboats.com/showthread.php?t=295070

I've checked everything on yourlist except maybe having the timing checked and having the carbueraters rebuilt.

 

[Don S]

Re: 350 Crusaders lose power after motors run for 10-15 minutes

Did you do these tests? http://forums.iboats.com/showthread.php?t=283363
I'm not askingk if you replaced some of the parts or looked at the system, I ask if you actually did the tests

 

[patswil]

Re: 350 Crusaders lose power after motors run for 10-15 minutes

Did you do these tests? http://forums.iboats.com/showthread.php?t=283363
I'm not askingk if you replaced some of the parts or looked at the system, I ask if you actually did the tests

Did I mention that both fuel pumps were replaced last summer,by a professional,... ethanol ruined the diaphrams in both

 

[patswil]

Re: 350 Crusaders lose power after motors run for 10-15 minutes

did all these, Not qualified or don't have euipment to test new fuel pump side

1. Clogged fuel filter/fuel water separator- changed twice
2. stuck anti siphon valve-replaced both
3. clogged fuel tank vent- checked- both clear

 

[Don S]

Re: 350 Crusaders lose power after motors run for 10-15 minutes

Your correct answer to my question was NO
By your answer, I doubt you even read the testing procedures.

 

[patswil]

Re: 350 Crusaders lose power after motors run for 10-15 minutes

Your correct answer to my question was NO
By your answer, I doubt you even read the testing procedures.

I most certainly did, Stanley.

I spoke to a marine mechanic who worked on my boat last year. He suggested that I replace the condensers,..which I did...too windy to test right now

 

[patswil]

Re: 350 Crusaders lose power after motors run for 10-15 minutes

T hanks for you rsuggestions. I replaced both condensers and the boat now runs GREAT

$8.00 and about 30 minutes

 

[Lyle29464]

Re: 350 Crusaders lose power after motors run for 10-15 minutes

wow what are the odds?

 

[patswil]

Re: 350 Crusaders lose power after motors run for 10-15 minutes

Actually, the problem still exists, I tohught it was running fine after replacing the condensers, but it's still doing the same thing- run 10-15 under load, then craps out, if the motors ar eidle for 15-20 minutes, it'll run again ...but only for 10-15 minutes. Have run the boat withouth gas caps, checked vents. I am frustrated. I'll basically rev up fine in neutral, but under load craps out

 

[patswil]

Re: 350 Crusaders lose power after motors run for 10-15 minutes

Actually, the problem still exists, I tohught it was running fine after replacing the condensers, but it's still doing the same thing- run 10-15 under load, then craps out, if the motors ar eidle for 15-20 minutes, it'll run again ...but only for 10-15 minutes. Have run the boat withouth gas caps, checked vents. I am frustrated. I'll basically rev up fine in neutral, but under load craps out

Can anyone shed some light on this please?

 

[Lyle29464]

Re: 350 Crusaders lose power after motors run for 10-15 minutes

I think it is starving for fuel. When it's cold the chokes help it out. I would shut off main tanks and hook a small tank to your fuel pump.

" I really didn't think both condensers when bad"

 

[patswil]

Re: 350 Crusaders lose power after motors run for 10-15 minutes

THis has been solved. The weights under the distributor, which expand with centrifugal force and thus advance the timing, had become rusted in place and thus, the motors couldn't advance the timing and she would subsequently die

Thanks for all the suggestions

 

[patswil]

Re: 350 Crusaders lose power after motors run for 10-15 minutes

THis has been solved. The weights under the distributor, which expand with centrifugal force and thus advance the timing, had become rusted in place and thus, the motors couldn't advance the timing and she would subsequently die

Thanks for all the suggestions