1988 Yamaha 40 elg trouble

[Redbreast16]

Looking for a little help, ran my outboard all day yesterday without a bit of trouble. I've never had any problems with this engine other than broken starter bolts. I filled the tank up this morning and ran for a couple hours checking my catfish lines. I let the motor idle while I went to back the trailer down the ramp. I pushed off the bank and drifted out in the river to trailer and the engine just died like I had switched it off. Drifted down the river til my buddy came to tow me back in. The bubble it tight, kill switch is connected, plugs are brand new, motor turns over and about the time it sounds like it's catching the starter quits til I back off the key any hit it again. Anyone have any advice?

[99yam40]

need to see if it is getting spark to all plugs.

If it is, then not enough fuel or too much will cause the cylinders to not fire/burn the fuel in them

[TownsendsFJR1300]

What's "The bubble it tight" mean?

As you just filled it up with fuel, did you drain the carbs, catching it and checking for any water?

Any water in the filter(s)?

If all those are clean, NO water, confirm you have spark.

If spark is present, fuel good, try spraying some pre-mix down the carb's and see if fires up (IE, potential lack of fuel)

[Redbreast16]

I have come to the conclusion that I may have been trimmed out far enough to keep the intake from picking up water. Overheating shut the engine down to prevent damage. Only problem is I'm not sure if this motor has that feature because I don't have a manual and can't find one. It's starting fine now and running like a top on the hose

[Redbreast16]

I have come to the conclusion that I may have been trimmed out far enough to keep the intake from picking up water. Overheating shut the engine down to prevent damage. Only problem is I'm not sure if this motor has that feature because I don't have a manual and can't find one. It's starting fine now and running like a top on the hose

[TownsendsFJR1300]

I have come to the conclusion that I may have been trimmed out far enough to keep the intake from picking up water. Overheating shut the engine down to prevent damage. Only problem is I'm not sure if this motor has that feature because I don't have a manual and can't find one. It's starting fine now and running like a top on the hose

You may want to check your water pump impeller. If it over heated from lack of water, that impeller got hot..

I have to doubt that was the issue.

IMO, it doesn't cost anything to simply drain the carbs and check for water/crap.

Boscoe should have a link for the owners manual, stand by for that.. Or do a search on-line...


**Your engine DOES seem to have a thermo-switch sensor, part #19:
1988 40ELG Yamaha Outboard ELECTRIC PARTS Diagram and Parts

[Redbreast16]

I do plan on changing the impeller before the next outing and run it some more at home just to test. thanks for the help!!!!!!!!!!!!!!!

[99yam40]

No Yamaha motor that I know of shuts down a motor from over heating