Yamaha 60 - buzzer - smoke - overheat?

[dunchumphrey]

I have a 99 2 stroke Yamaha 60hp oil injection, was running fine after recent service, but over last 2 trips engine note was louder and maybe rougher until today when buzzer came on and smoke poured out of the 2 holes just under the power head. Definitely smoke, not steam, normal jet of water was still visible from pilot hole. Waited until cooled and carried on at low 1500rpm (seemed almost normal) until more smoke and buzzer again. Another wait and a few hundred yards later same thing. One more wait but when restarted big puff of white smoke and no water from pilot hole now. Motor does still run and Yamlube level OK any thoughts?

 

[rodbolt]

Re: Yamaha 60 - buzzer - smoke - overheat?

hello<br /> not knowing what the recent service entailed nor if its a tiller 60 or a remote 60 I have to ask what did the tach visual indicator show?<br /> that motor only has 2 alarms. low oil level and overheat. sounds like a case of the overheats. the tell tale only indicates the pump works not that the engine is cool. time for a cyl head retorque and compression test. if the compression is ok then its time to inspect the cooling system.

 

[Silvertip]

Re: Yamaha 60 - buzzer - smoke - overheat?

The fact that the engine puffed a huge cloud of white smoke is an indication of a popped head gasket. As rodbolt suggested, a compression test is in order. If that turns out to be the problem, determine why it failed before placing the engine back in service. Thermostat and impeller replacement would be in order as well.

 

[dunchumphrey]

Re: Yamaha 60 - buzzer - smoke - overheat?

HI, thanks for your help, this is the remote steer FETO model. The tach was showing normal although when the buzzer sounds the revs drop and are limited to 2000rpm. Not sure how it does this though. The service was full lube, all functions checked, new filters, new plugs. Will keep you informed.

 

[dunchumphrey]

Re: Yamaha 60 - buzzer - smoke - overheat?

Just checked out the plugs, all show a fair bit of oil I'd have thought good news, although the cylinder heads looked covered in black oily gunge. Could the smoke from the 2 holes actually be steam mixed with exhaust gas?

 

[dunchumphrey]

Re: Yamaha 60 - buzzer - smoke - overheat?

Gave up DIY and gave it to an expert. <br />Turns out the plastic lining inside the impeller had sheared away from the rubber and was spinning away merily on its own. At low RPM there was enough drag to turn what was left of the rubber but at higher RPM the plastic just spun on its own. The white smoke I'm assured was definitely steam and there would appear to be no other damage - Cylinder compressions all 125 psi. <br />One odd thing though, the mechanic said he checked the impeller only weeks before and it looked OK? Anyone heard of this happening before, could there be another underlying cause? perhaps.

 

[31900]

Re: Yamaha 60 - buzzer - smoke - overheat?

I would think that if someone went to the trouble of stripping the motor to that stage, it would be to replace the impeller as you would every 2 years. No matter how good the impeller looks, at that stage you would replace it because it has a limited life. Can you be sure your man actually did the work?

 

[rodbolt]

Re: Yamaha 60 - buzzer - smoke - overheat?

see what I say about the white plastic hubbed impellers used on the 98-99 motors. all failed. all spun the hubs. the service impellers went back to black. I had motors that spun them in 5 hours.<br /> the 98-99 pumps were bogus. had more hub failures with them than all other yamaha and omc and mercs combined.<br /> but no one will admit there was a problem and most times warrenty would not cover it. was funny that prior to the 98-99 pumps I had never seen a hub failure on a yamaha.

 

[randyroeder]

Re: Yamaha 60 - buzzer - smoke - overheat?

Originally posted by rodbolt:<br />[QB] see what I say about the white plastic hubbed impellers used on the 98-99 motors. all failed. all spun the hubs. the service impellers went back to black. I had motors that spun them in 5 hours.

 

[randyroeder]

Re: Yamaha 60 - buzzer - smoke - overheat?

how do you know which one you have?(improved black or troubled white)

 

[rodbolt]

Re: Yamaha 60 - buzzer - smoke - overheat?

reelgreen.<br /> most the white hubbed ones are long gone. the aabove motor suffers from a lack of maint. the maaint schedule for water pump inspection is 200 hours OR one year, whichever occurs first. anytime I have the pump apart it will get at least an impeller kit regardless of how it looks. sometimes the first overheat is the last. 2 strokes dont like to get hot. no one ever pays attention to the OR part of the schedule. they quit reading at the hour part and to many dealerships only do a 100 hour service which does not cover annual maint. 5 one hundred hour services still dont equal one 200 hour service and some of the newer V6 and 4 strokes have 400 and 1000 hour points that will never be done. quite a bit of the maint can be done by the average backyard man. but its mandatory the back yard man do a bit of reading first on how the system works and sometimes why and other trimes what happens if it dont . after cooling system failures fuel system failures,especially bad ful pumps, kill more yamahas than about anything else. fuel pumps are cheap. replace them every 3 years and they rarely fail. wait till they fail and you cab do it at the overhaul.<br /> but to answer the how do you know question. without having it in your hand there is no way to tell. if it has not been changed in 2 years or is original it may be on borrowed time.

 

[31900]

Re: Yamaha 60 - buzzer - smoke - overheat?

I say again, are you sure your man did the service? He said he checked the impeller only weeks before and it looked good. In my opinion, if he went to the trouble of stripping the lower unit down and looking at the impeller, a professional would have replaced it regardless of its appearance. That's what that service is all about. It should have been replace then and your problem would not have happened.