98 Force 40 hp issue

[Gauvol]

I bought a used aluminum bass boat with a 40 hp force outboard. Used it for a month and a half without issue. Two weeks ago, while idling over a ledge, the engine died. I had run several times earlier in the day without issue. Last week, again after running and idling around the lake without issue, I idled in gear out of a pocket and it quit. Both times I was able to restart after 10 or 15 minutes and put it on the trailer. The common denominator between the incidences is it has been well up in the day when the problem has occurred and was very hot both days. Never happens early in the morning. I have not begun replacing fuel lines, bulb, filter or cleaning carbs yet. Any ideas what is happening?

 

[jerryjerry05]

Might be getting hot? Test the system.
Try grounding the temp sensor, key on and the alarm should sound off.
Yes? then the buzzers working, but it still might be getting hot.
You'll need a temp gun to see if the sensors working.
You can test the sender with a meter and a pot of hot water.
You sure the gas is fresh and no water?
Pull the thermostat and see if it's working right? dunk it in a pot of hot water and see if it opens?
it's a 130d

Change the impeller? it could be 20 years old???

Next the fuel system might be sucking air somewhere?
You have a built in tank or use a portable?
The portable, it can have a bad connection or the vent isn't open enough?
The built in, the vent hose can be blocked and not letting in enough air?

Possible: the pack is failing when the heat of the day reaches it's peak?

What's the rpm's at idle and in gear?
Should be about 750-800
Too low and it can just stall when hot??

I'm sure others will chip in with more.

If you need? outboardignitiondotcom has test procedures for your ignition.

 

[Gauvol]

Motor has never shut down at speed, only at idle. And only as the day has heated up. Shut down for over an hour before idling out 100 yds when it stopped. Would water in the gas only show up when the day is hot? Never has a problem with gas from that station and the gas is fresh. Impeller is 3 yrs old. Built in tank

 

[jerryjerry05]

That sounds like it might be getting hot?
You do the tests I posted earlier?

 

[Gauvol]

Thank tou for your help. Not yet, just wondering why it would show up while idling not running down the lake?

 

[jerryjerry05]

Not pumping enough water at idle?