Yamaha Problem

[bruce roorda]

Re: Yamaha Problem

Just a quick reply from someone who owned one of these engines from new in 1987.<br />This was the worst engine I owned partly due to the setup on the boat I suspect.I never got the problem sorted properly despite putting massive fuel filters in place with watertraps.<br />My engine sounds the same as yours.Runs fine but wouldnt pull the revs.<br />Outboard mechanic would clean carbs and it would run fine until it a few months.<br />Problem would return.<br />Apparently these Yamahas run very fine jets and that was the problem.<br />The cause was dirt and water coming in from somewhere.<br />Suggest you learn to pull carbs apart.<br />Bruce

 

[BillP]

Re: Yamaha Problem

Make it easy on yourself. Pumping the fuel bulb should tell if a pump diaphram is bad. It has always worked for me...and you cannot always tell if the diaphram is bad by visual inspection...they can be porous without seeing it. This all learned from the school of hard knocks. The pump diaphrams should be changed by now anyway. <br /><br />If you have those small jets try a small inline filter as close to the carbs as possible and install a large disposable canister type as a prefilter.

 

[bruce roorda]

Re: Yamaha Problem

I had 2x extra filters added to my Yamaha so there were a total of 3x in the fuel system.The last one was a cartridge type with a water catcher.It was a top of the line model and the gunk still got into those jets!!!

 

[cjg]

Re: Yamaha Problem

Thanks guys<br />I will do as Capt Ken suggested and try the bulb as this sounds like an easy first step to eliminate the fuel pumps ( I hope it is just the pumps )<br />I will keep you informed