**New** 2.5hp Yammy 4 stroke problem

[Drowned Rat]

Hi guys. I just traded up to a never used 2005 Yamaha 4 stroke 2.5hp. It has never touched the water. It starts up fine and idles fine, when advancing the throttle, it bogs down and will die if you don't back off back to idle. If you advance the throttle very slowly, it runs up fine. Any ideas on this? The motor was sitting for a while, I'm assuming with gas in it. Would old gas cause this symptom? This is a brand new engine. Thanks for the help.

 

[edzzed]

Re: **New** 2.5hp Yammy 4 stroke problem

if it was sitting for months and months old gas would be a problem. my m/c sits for 6 months of the year. once a month i run the engine just to get new gas in the carb. not necessarily fresh gas but move the old stuff out. gas will turn to varnish plugging up the jets and that is what may have happened in your case. those carbs are pretty simple to disassemble. i'd do that and soak the stuff in carb cleaner for a few days and make sure the jets and orifices are clean. Ed

 

[mattttt25]

Re: **New** 2.5hp Yammy 4 stroke problem

sure sounds like a fuel problem. does it have a cartridge filter you can replace? how are you testing this if it hasn't touched water? if you're throttling up in the driveway on muffs, could that be the issue? i was under the assumption you didn't want to do that.

 

[Drowned Rat]

Re: **New** 2.5hp Yammy 4 stroke problem

mattt, I've got it sitting in a large container of water and I don't run it up much, maybe to 2500 or so, but that's enough to see it try and bog down. The fuel thing is probably it because I think it's been sitting for some time, maybe a couple of years, without use.

 

[JUSTINTIME]

Re: **New** 2.5hp Yammy 4 stroke problem

carbs or bad fuel