Mercury125 Fuel delivery?
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- CaptReelThyme
- Posts: 157
- Joined: October 2nd, 2011, 1:39 pm
- Location: St. Marks & TLH
Mercury125 Fuel delivery?
Trying to figure out my outboard problem. Boat has run great. I was out yesterday and was trying to get back before the storm. Motor fired up and would idle every time then cut off. I refired the motor took it out of gear and increased rpm's. I would drop down, then get it into gear, I would run then it would cut off. I trimmed motor up, checked over prop and water intake. nothing. The motor was staying cool and thermostat was low. Not sure if it is fuel filter or fuel/water separator or something else completely. I store it at Shields. I guess I will have them look at it. Any ideas or recommendations?
Re: Mercury125 Fuel delivery?
had the same problem with my merc 150 saltwater 2 stroke. after much trial and error and pulling half of my hair out i found out that it was my ignition harness. once my mechanic replaced it i havent had a problem since. hope this information helps.
- CaptReelThyme
- Posts: 157
- Joined: October 2nd, 2011, 1:39 pm
- Location: St. Marks & TLH
Re: Mercury125 Fuel delivery?
I will look into that. I had no problem getting it started. It was real sluggish. I ran WOT at 5knts and if the motor seemed like it was gonna cut out I choked the motor. But still I was not getting any power. The Primer bulb seemed to get week as well. that is why i think it maybe fuel related.
- Dubble Trubble
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Re: Mercury125 Fuel delivery?
Check the fuel line from water separator filter to the motor. If the line the bulb is inline with is grey with red print, you got a line disintegrating. Those lines were notorious to do that, ethanol or not. If that is it, you probably will have to put a kit in the fuel pump too since the pieces get all in the pump.
This is what the pump will look like.

I had the same issue with mine.
Dubble
This is what the pump will look like.

I had the same issue with mine.
Dubble

The more I know about something, the more I know that I did not know as much as I thought I knew that I knew.
- onefishtwofish
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Re: Mercury125 Fuel delivery?
That looks familiar Dubble.
Ducks, turkeys, flats fishing. Who has time for golf?
Re: Mercury125 Fuel delivery?
Yea that sounds like a fuel line issue if the bulb is getting weak.when I had my problem my engine would just randomly cut out but would easily crank back up once key was cycled. There was and weakness in one of the wires in the ignition harness that once a certain amount of voltage was applied at high Rpm's would open up and cause the engine to shut off.
Re: Mercury125 Fuel delivery?
I have a merc 150 for sale it stared having a slight knock so I just decided to replace it with my back up johnson 120. The merc would be great for parts or to fix I just know nothing about motors so I would rather replace if I can. It runs and will start with no problem I just didnt wanna push my luck 20 miles off shore. Lookin for $300 obo comes with everything. All harness two covers etc.
- Chalk
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Re: Mercury125 Fuel delivery?
Look at your fuel line vents as well...if you have a water sensor like Yamahas under the cowling that may be the problem as well
Re: Mercury125 Fuel delivery?
Oreocwby, what other info do you have on the engine; year, model, etc. may be interested