2005 Merc 50hp Idle

qwest

Seaman Apprentice
Joined
Aug 9, 2020
Messages
45
Hi,

I recently purchased an 01' scout 162 w/ a 50hp merc 2 stroke (ELPTO) that seems to have some idle issues. I suspected dirty carbs/gas at first as the motor had sat for over 2 yrs. I then cleaned the carbs and ran an external tank but the motor continues to die at idle.

If I start it w/ a bit of throttle it will stay running, but as soon as I drop it to neutral it starts to fade out until it dies. Is there a good way of going about adjusting the idle stop screws and linkage? Anything I should look into before taking this step?

Model #1050412DD

Thanks in advance
 

brodmann

Chief Petty Officer
Joined
Jun 17, 2008
Messages
426
When some folks here say they "cleaned the carbs" it sometimes means they sprayed a little carb cleaner into the throat of the carb. I've included a diargram of your carb. Cover #10 has to come off and all the little passages in there need to be cleaned out and have compressed air forced throught them. If you don't have a compressor, carb cleaner with the little straw on it is the next best thing. I'd start with the mixture screw screwed all the way in and then 1-1/2 turns out. If you have a tach, at what point is it shutting off? The main jet starts kicking in at about 1,000 to 1,500 RPM's., so if it won't idle below 1,000 RPM's, its because there is a blockage in your idle circuit. That's up top under that cover.
 

qwest

Seaman Apprentice
Joined
Aug 9, 2020
Messages
45
thank you for the response,

It will only start when given a bit of throttle and choked. It will then continue to run as long as it stays above around 2000 rpms. I've let it run for a few minutes around 2-3k rpms and then drop back down to idle, but it immediately starts to fade out and die. I believe the motor is supposed to idle @ 650

I took all 3 carbs completely off along with the top plate and cleaned thoroughly (to my knowledge) but I can check again. Is there an idle mixture screw on each carburetor?
 
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