2006 f60 YAMAHA 4 STROKE WON'T REV OVER 3,000 WIDE OPEN?

[crimar30]

It was running fine, then suddenly started vibrating & running very rough, so I shut it down and went home, I changed the water separator thinking that may be the problem, but no. The next day I took it back out after replacing the water separator filter, now it idles ok, but won't rev up over 3,000 rpm. Now I'm thinking I read somewhere that if it overheats, it won't go over 3,000 rpm, could this be it? Anyone know if my engine has an overheating alarm.

 

[ondarvr]

Yes your motor has an overheat alarm, whether it works or not is a different subject.

 

[crimar30]

Do you know if the water pump was bad, would that limit the revs?

 

[ondarvr]

A bad water pump won't limit the RPM's, overheating can.

 

[99yam40]

overheat does not happen at start up. has to run awhile to overheat.

I think the RPM reduction on over heat on Yamahas was around 2K not 3K
so I would be looking for other reasons for the motor problems

 

[robert graham]

Remove each spark plug and inspect carefully for any indications....like carbon or fouled plug...good place to start your troubleshooting...

 

[crimar30]

Replaced the plugs this morning, ordered new water pump impeller. When I ran it today, I noticed the thermostat cover got hot VERY fast, is this normal? Never paid any attention to it before. Ordered a new one while I'm ordering, anyway.

 

[robert graham]

If this motor has carbs have they ever been cleaned? If it's injected have the injector screens ever been cleaned or replaced? Sounds like you're just losing power on one cylinder.

 

[crimar30]

It's fuel injected, I'll have to look up injector screen. Thanks. Is that an easy thing to do?

 

[robert graham]

Each injector has a small screen that can get plugged with debris...then you lose power on that cylinder. My motor has carbs but if I ever get one with injection I'll figure out a good preventive maintenance for injector removal/ inspection/ cleaning/ whatever to eliminate these issues. I just drain each carb float chamber at lay-up time to eliminate plugged jets. A plugged injector or carb jet can be more than an inconvenience on the water....it can lean out a cylinder and do real damage$$$$

 

[Sylva-Ranger]

Some Yamaha 60 have a water detector sensor at the botom of the fuel filter bowl, and if youy have 2 wires that comming from that bowl, it can have a protection.

​You can try jumping thoses wires and make a test ton confirm operation.