Strange happening

[Trojan]

I last used my boat on the fourth of July weekend. Everything went well as usual. 2 Days ago I went to check out the boat for a planed short voyage. For some strange reason the starboard engine refused to start on the first rollover. What the he-- is going on. I advanced the throttle half way and the engine lit right off. It runs, but now it would not idle, Anything below 1,100 rpm and the engine would die. It would run just fine above 1,100. I thought well I have a dirty filter. So I changed both filters and fired it up as in the past. It still would not idle. It would rev up to WOT with no trouble but drag it back down to idle and it would just die. I let it run at 1,100 for 5/10 minutes in gear. Running it up and down. Leaving it idle at 1,100 rpm out of gear for a few minutes it began to rev up and wonder gaining the rpms that half throttle is supposed to produce. Reducing the rpms and the engine would quit. I got POed and shut the engine down. After it sat for a few minutes I blessed it gave it a wammie and restarted the engine at half throttle and it took off high in rpms so I pulled back the throttle and damn if the engine didn't settled right down where it should be and it's running great as always. Any of you motor heads got any ideas as to what might have happened. My only guess is we had extreme heat and humidity here and the engine setting idle for a month might have been the issue. It's got me stumped for now.

BILL

 

[geofish]

I'll have to try that blessing thing before the whamming... maybe she will respond the same..and purr!

 

[Trojan]

Well I had the boat out tonight and it started just fine. I ran it up the river for about 3 hours at different speeds and to my surprise it operated just great. So I don't know. I guess I will just have to wait and see. Don't know if it was the blessing or the wammie. It was a strange. I hate it when things happen to something that is mechanical and you can't find a reason why.

BILL

 

[geofish]

Intermittent or disappearing problems bug the heck out of me as well...

I have thought about this event of yours and nothing really pops out at me other than some type of obstruction in the fuel system that the pump could not overcome at low speeds. Maybe you will see something in the racor bowl next time you look. If you have free time it might be a good idea to disassemble the racors and the fuel lines and clean/blow out everything out and put it back together again.
Did the engine just shut down quickly at just below 1100 rpms or was it a slow drawn out wheezing stall?

I don't know what effects the humidity would have on your engine I live and work in fairly dry climates.
You will end up with some peace of mind by cleaning the fuel lines and filters and if you actually find something concrete you will feel much better!

Good Luck,
Geo

 

[Top Shelf]

Just a thought...had a similar problem on start-ups. check the fuel shut down solenoids to ensure they are fully retracting after you shut down. one of mine was binding and causing similar issues. thx

 

[Trojan]

I don't have racors I just have the old canister type filters. I changed both filters and the problem seams to have gone away for now. The rpms at 1,100 would maintain, but if you dropped below 11 the motor would just slowly continue to loose rpms and stop.

BILL