115 mercury dies after running

alabamaboy

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Mar 10, 2008
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I have a 1986 Mercury 115. Last week had it in the shop because it would idle, then die out when put into gear. They changed the fuel pump diagpham, and cleaned float bowls. Carried the boat out yesterday cranked right up, warmed it up a little, put it in gear and off we went, ran about 10 mins, then slowly started losing power, could bump the throttle and it would come back up for a bit, then would die again, finally died all the way, and would not recrank. Waited about 10 mins, and then it would crank and run about 5 mins or so then do it again. Anybody have any ideas? Thanks
 

Bondo

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Apr 17, 2002
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Re: 115 mercury dies after running

Ayuh,....

Sounds like it's Starving for Fuel,.....

Start at the Tank,+ work your way to the motor,..... Something is restricted....
 

j_martin

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Sep 22, 2006
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7,474
Re: 115 mercury dies after running

When it's dying, what is the primer bulb doing? If it's flat, something is plugged up at the tank. If it's full, (wouldn't be firm) what happens if you squeeze it. Does the engine pick up, or die further?.

John
 

alabamaboy

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Mar 10, 2008
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Re: 115 mercury dies after running

The bulb was not flat, it was full when i went to pump it back up. I took one pump to make it hard again.

What about it having a bad thermostat and getting to hot?
 

TuckerD88

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Mar 9, 2008
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Re: 115 mercury dies after running

I had a 15hp do that to me and it ended up being the water pump
 

alabamaboy

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Mar 10, 2008
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Re: 115 mercury dies after running

Well I dropped off at the repair shop, They said the water pump was dry rotted, and coming apart. They changed it and says it should be good to go. If it was peeing water while idling, would that not mean that it was a good pump? or that it is slowly coming apart and then finally did or not work at high rpms?

I guess we will see this weekend.

Thanks
Jimmy
 

alabamaboy

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Re: 115 mercury dies after running more help needed.

Re: 115 mercury dies after running more help needed.

Carried the boat out Sunday afternoon, It fired right up, went down the lake about 10 mins, and it slowly started losing power, it never did die, but it would only run right above idle. Stopped and fished for a little bit, then cranked up to move, the motor will still not run over idle hardly at all. It will rev up and idle at higher rpms than it will run at if I put in warm up.
The primer bulb is staying hard; I changed the fuel line from the tank to the motor.

Any ideas or help will be great appreciated.
 

CharlieB

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Apr 10, 2007
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5,617
Re: 115 mercury dies after running

First thing I would check compression to see if you have any damaged cyl's from the overheating.
 

jims3000

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Apr 27, 2007
Messages
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Re: 115 mercury dies after running

i have a 85 merc 150 almost the simular problem i took the covers off and ran the motor and the top carb was flooding out so bad it was running down into the other carbs.it would run like a sparkplug was trying to foul out one minute running fine the next it would run like crap.
 
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