carburation anyone

hi i have a 72 merc 40hp 2 cyl, my problem is this if i adjust the low speed needle to get the eng to idle and go into gear smoothly and stay running it
looses its top end power no good over half throttle. if i back the low speed
needle out it will not idle unless i move the idle lever way up and then have
to be play with the idle lever while putting in gear but it will run much better
at top end. i have had the carb off and it did have a clogged orifice. Does it have a high speed adjustment i do not see one. Also when the needle is backed out for top end power it starts to leak fuel. any idea will help THANKS

Re: carburation anyone

Oops. I click on wrong button and posted answer twice.

Re: carburation anyone

I can not guess at the partucular cause of your problem based upon your description of running conditions. It could be many different things. If my motor had your symptoms, I would first clean the carbs and do a complete link and sync. If that does not fix things, I would next check for satisfactory ignition and fuel delivery using various troubleshooting methods, which you will find already described many times in various threads on the forum. Or... you can check the ignition and fuel before cleaning the carbs and doing a link and sync. Either way will get you closer to solving the problem. Just my thoughts..

Other more experienced users on this forum may recognize your specific problem based upon your description of how the motor runs and zero in on the correct fix. If they do, it could save you the effort and cost of doing what I suggest above.

Re: carburation anyone

I'd rebuild the carb, complete with a carb kit. Change out the packings, sounds like an airleak on the low speed jet, one reason your getting gas out would be if the packings were shot, and fuel can "backout" the low speed jet when you richen up the mixture.

Re: carburation anyone

Thanks i will rebuild the carbs with complete rebuild kit, after i go fishing
this friday of course lol......