Clogged Fuel Filter? Pick-up?

[sailsmanship]

Bought a 97 Seamaster with a 5.7l Mercruiser/Alpha One. Have had it out 8 times this year and ran great every time except today. Other 7 times the water was fairly calm. This time the waves were kicking pretty good.
On the way in the motor died. Fired right back up. went a ways them did it again. At cruising RPM it will completely stall, but if you run it about 1500 RPM and she starts to die, you can chop the throttle and save it from stalling. Any time it would stall. it would fire back up . Could this be a symptom of a clogged pick-up or filter and it became this way when the rough seas stirred up the bottom of the tank?

 

[tystick]

Re: Clogged Fuel Filter? Pick-up?


Could this also be a bad oil pressure switch?

 

[Don S]

Re: Clogged Fuel Filter? Pick-up?

Yes it could be a clogged filter, or even water in the filter. Even a partially clogged fuel tank vent fitting.
I doubt it would be the oil pressure switch. If that were the case it would die completely every 10 or 15 seconds after starting. It would restart, but would again completly die do to lack gas in the carb, and you would never be able to get to cruise speed or even on plane before it died.

 

[sailsmanship]

Re: Clogged Fuel Filter? Pick-up?

I thought about the vent fitting. I opened the fuel tank filler once while underway to see if that would help but it did not. Wouldn't that act like venting?

 

[lilmandavis]

Re: Clogged Fuel Filter? Pick-up?

change the filter, dont just dump it out and reinstall. i would though dump it in to a clear jar and see if there are signs of water in it. maybe check the fuel pressure as well!

 

[sailsmanship]

Re: Clogged Fuel Filter? Pick-up?

Follow-Up....... Replaced both fuel filters. No water in the big one, particles in both but not anything more than what I have seen in other boats I've had. What I did see is that the spark arrestor had about a half inch of cottonwood packed around it. ( We have alot of cottonwood trees around the marina). Removed that and took it out for a couple hours yesterday. Ran all RPM ranges from idle to WOT. Ran Great.. Could the cottonwood have caused the problem ?. The only other thing was that is was calm out, unlike when the problem happened. Also should I still pull the pick-up and check it out. It is a *&#@* to get at.

 

[tommays]

Re: Clogged Fuel Filter? Pick-up?

See what happens BUT i had gotten a good amount of water in my tank over a 9 year period and took it apart and carfully sucked the water off the bottom

I have had no problems after doing that


Tommays

 

[Haut Medoc]

Re: Clogged Fuel Filter? Pick-up?

Well, it needs gas & air.....
So the flame arrestor being clogged can't be any help....
Of course changing the fuel filters can't hurt either.....
The pick up?
Well, it wouldn't hurt to check that either....
I guess you wont know until you recreate the conditions that caused the initial failure, but i think that you are headed in the right direction.....JK

 

[sailsmanship]

Re: Clogged Fuel Filter? Pick-up?

Sorry to keep beating a dead horse, but I took it out today in calm water and after twenty minutes of running at steady 3500 RPM it started again. I am supposed to take this boat on vacation a week from now and want to get rid of the problem so as not to ruin it. Do you think that if I clean out the pick-up and replace the mechanical fuel pump, I might eliminate 95% of the possibilities of the problem left?

 

[cheburashka]

Re: Clogged Fuel Filter? Pick-up?

I'm wondering about that cottonwood. A flame-arrestor is a rather poor air filter. The holes are big enough that debris can get in under pressure. You may have sucked something into the intake and plugged some air orifices. It sounds carb related, but not necessarily a problem of fuel delivery. Have you verified that there is fuel in the bowl when it stalls? The accellerator pump should squirt out fuel when you pump the throttle. Have you ever had the carb rebuilt? If not, it might be time to do it!

 

[sailsmanship]

Re: Clogged Fuel Filter? Pick-up?

Update.... FYI .. It was a partially clogged pick-up in the tank. Runs great now with no problems . Thanks for the help..