surging problem (225 Excel)

[Bandaid]

After changing fuel pumps, removing in line fuel filter and switching to the high end 100 micron Yamy fuel seperator I am getting surging problems always on the trip home (only) usually after running the boat for about 1-2 hours. Always between 3800-5000 rpm's. Really frustrating and suggestions would be appreciated!<br />Charlie

 

[rodbolt]

Re: surging problem (225 Excel)

then you will need to test it while its surging, you will need a fuel system vacum guage attached at the fuel pump intake, a diagnostic test lamp, beaware automatic oil tranfer does not occur with the lamp installed and the TPS harness to check the 5V reference and the TPS output voltage while its surging.

 

[Ray Neudecker]

Re: surging problem (225 Excel)

This was somewhat of a problem around 4000 RPM's when they were new. Yamaha's answer at that time was to adjust the oil injection lever for less oil. This helped some times. Normally any surge would be related to fuel restritions. I would look to rebuilding the carbs replacing the bowl gaskets and needles. Then if the problem still occured, I would do as rodbolt says. You might try to stop and back out the jets to drain the carbs. If when you start back up, the problem goes away even temporarily. you likely have a needle trying to stick. Do not reuse the bowl gaskets if you take the carbs apart, they disintergrate in the carbs causing the problem to reoccur.