Adjustment Screws

[RetroActv]

What if your outboard manual tells you to turn your screws out 1.5 turns on the carbs, but you have to turn them out 3 to 4 turns to get it to run smoothly with the ear muffs on? Does this imply dirty carbs or some other problem?<br /><br />Motor in question is Yamaha 50 hp.

 

[rickdb1boat]

Re: Adjustment Screws

I would say that 3 or 4 turns is too much to acheive proper running condition. I would rebuild the Carb(s) and set the screws to 1 1/2 turns out and fire it up. Bet it runs better than before. Pay special attention to the float settings and the needle Seats! Buy a rebuild kit from your dealer Or NAPA store. It will have all the Parts you need to make it good as new. Make sure you have a Manual handy to refer to!! Good Luck,

 

[rolmops]

Re: Adjustment Screws

Hello.<br />By what you tell us,it does sound like there is a lot of gunk in your needle housings.However if it runs smooth when you open it 3 or 4 turns,that would mean that the small passages are still open.<br />Before you rip your carburator apart,why don't you try some serious carburator cleaning agent in your fuel?<br />You may want to try and take the screws out and spray some seafoam or simular stuff in the housing, screw the needles back in and let it sit a few minutes.<br />It is usually a good idea to adjust your carburator screws under a load e.g. in the water while you move.This may make for a very different adjustment.<br />good luck.