boat stalls at high speed

[djk117@optonline.net]

It's a 1995 60 hp mercury. The boat sat over winter without being fogged.we were told that there was water in gas tank.tank was drained twice. We are using a new portable tank with fresh gas.All parts were cleaned & plugs.the motor started on the second turn on a flush kit. ran great at idle, then gave it a little more gas at a steady speed the engine would automatically reve itself at higher speed and then stall out.In the water it would run great and then again when we kick it up the motor it stalls, it will start after a few turns but idle ruff and stall out. help

 

[Perfidiajoe]

Re: boat stalls at high speed

I would start by removing cleaning & rebuilding the carb., sounds as if it may be gummed up. Gas will turn to a varnish like substance in time, & will mess things up pretty good. Clean the filter also, & water seperator too. Good luck, Joe

 

[chrisczub]

Re: boat stalls at high speed

I second that! Had the same problems all linked to crapped up carbs. Rebuild and reinstall!<br />96 90HP Mercury

 

[djk117@optonline.net]

Re: boat stalls at high speed

whats a water seperator?

 

[chrisczub]

Re: boat stalls at high speed

I water seperator is connected between your tank and motor and collects any water in you gas before it makes it to your motor. I took the carbs completely off of mine, cleaned them then reassmbled them. I also rebuilt the fuel pump for $11.00. Runs like a chanp now. <br /><br />Hope this helps

 

[got_fish?]

Re: boat stalls at high speed

About that water seperator. I never used one, but, wouldn't that seperator cause a fuel restriction in certian cases?

 

[chrisczub]

Re: boat stalls at high speed

It should not restrict the fuel flow. Think of it as another filter.

 

[djk117@optonline.net]

Re: boat stalls at high speed

Chris did you check your compression? My motor is pushing out about 120-125 psi is that about right?

 

[chrisczub]

Re: boat stalls at high speed

Mine is 125 all 3 cylinders. Is was a definate fuel issue. I would be able to run WOT for about 15-20 seconds then it would drop to about 2000 rpm. It wasn't too bad to take my carbs out but the bottow one is a little trick to get back in since there are no studs off the block for that one just thelong bolts that go through the silencer. <br />Also mine did the same thing as yours and would jump up to a higher RPM then drop out on it's own. When you take the carbs off though, make sure you know which ones went where as they can be slightly differnt and not work/fit properly if but back on in the wrong positions.<br /><br />Water seperator is not a must but is good to have. Haven't installed mine yet but it will be there before the next trip out.<br /><br />Good Luck.

 

[chrisczub]

Re: boat stalls at high speed

Any luck yet? Hope all is going well.

 

[djk117@optonline.net]

Re: boat stalls at high speed

Well chris, thank you for asking, we changed it all, rebuilded the gas pump, new plugs, new water pump, rebuild the carbs. I even found a wire that was sandwiched in behind my gas pump that was bare and grounding out the fuel injector, put in the water yesterday and it ran great, just a few twicks to the carbs and hopefully we'll be fishing by midweek if the weather holds up.

 

[chrisczub]

Re: boat stalls at high speed

Glad everything worked out. Bare wires are not good either! Good luck!