50HP 2004 Mercury Stalls

[DonWilson]

Hi guys, new to this forum & need a little help.

I have a very low hours (100) engine that stalls under load at half to full throttle. No warning, just quits & goes dead. Then restarts right away.

A mechanic questioned the prop size (something about control chip)???????

Don't know where to go next. Any ideas?

Don

 

[Don S]

Re: 50HP 2004 Mercury Stalls

Is it 2 or 4 stroke, EFI or carbed?

 

[DonWilson]

Re: 50HP 2004 Mercury Stalls

Thanks Don,

2 stroke & carb.

Hope this helps,

Don

 

[Don S]

Re: 50HP 2004 Mercury Stalls

Well, being a carbed 2 stroke eliminates any "Control Chip" problems as you don't have any such thing.

When you say it starts back up, does that mean immediatly? Do you have to pump the fuel bulb?
Does it happen around the same time, like 1 or 2 minutes when running or does it do this at 30 seconds one time and half an hour the next time?

 

[JustJason]

Re: 50HP 2004 Mercury Stalls

does the primer bulb go flat?? does pumping the primer bulb while at/near WOT/stall speed remedy the problem??

 

[DonWilson]

Re: 50HP 2004 Mercury Stalls

Thanks guys, I really appreciate your VERY prompt responses.

RE: "Control Chip", guess I have to wonder about my mechanic.

Don it does restart on 1 - 2 attempts & does not require pumping the bulb. Once it is restarted, there is no pattern for the next stall. My not stall at all or go 15-20 minutes at mid RPM before stallaing, again.

captJason, primer bulb does not go flat. Stays hard.

Don

 

[JustJason]

Re: 50HP 2004 Mercury Stalls

whens the last time it was fully tuned? as in new plugs, all filters, carbs checked for sync and timing checked? if it's been awhile... you should start there

 

[DonWilson]

Re: 50HP 2004 Mercury Stalls

captJason,

Full tune done in the spring.

Mechanic said he did all the items on your list. New carb kits, new water pump & new plugs. Plus, all adjusting / tuning.

This was a new motor to me this year. So, I have no experience whether this problem existed before the tune-up.

Don