Mariner 40hp bogging at WOT

[mikecarr4]

Hi all,

I created a post regarding this issue a couple of weeks back but still having the same problem?? I'll try and give as much info as possible...

I have a 1993 2 stroke 40hp Mariner with twin Kei Hin Carbs...and running a 10 5/8 x 12 Prop.

The problem I have is that the engine bogs down at WOT or if I go over a decent wave it tends to do the same and then stall...

The engine starts again after a couple of pulls....It sounds like its flooding the engine when it bogs down but also sounds like fuel starvation when it picks up again??

I have renewed the spark plugs, used brand new fuel with quicksilver oil, cleaned the carbs out until gleaming, checked the mixture screw is correct (1 3/4 turns out) and tuned it according to the manual...The only thing I did find when stripped the carb down was the 2 floats seemed to be set at slightly different angles

I went out with it yesterday and was ok at WOT for 20 mins then died on me..?? I then had to wind the mixture screw out a good few turns just to start it again and then screwed back in slightly so it would run...

This is a tricky one so any help would be appreciated , Thanks.

 

[Faztbullet]

Re: Mariner 40hp bogging at WOT

Replace the fuel pump diaphram and rubber check valves...

 

[mikecarr4]

Re: Mariner 40hp bogging at WOT

Ok thanks I'll try that next...

 

[scrapeeape]

I'm having a similar issue with my Mariner 40hp. It's like an 1984-1987. It starts, idles, and runs fine until I throttle it to get out of the hole. When at full throttle it just boggs down and will only get up to about 12mph. I have changed the plugs, fuel, cleaned the fuel filter and carbs with no change. Also a foot note some of the parts on the motor say Mitsubishi .
Any thoughts

 

[GA_Boater]

scrapeeape - Welcome aboard.

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