Engine Cutting Out

[ntermini]

When I drive the boat around 4,000 RPM's for roughly 10-15 minutes the engine will loose power/cut out but stay running. The RPM's will fluctuate up and down, the engine almost seems like it is bogging. I try and raise the throttle and the engine just bogs and sputters.<br /><br />If I bring down the RPM's to 2,500 for 15-20 seconds then raise the RPMS's again the boat will run for a few minutes then repeat the problem. I can also put the boat in neutral for 30 seconds then go back up to 4,000 RPM's drive for a bit then the problem starts again.<br /><br />Does anyone have any ideas? Thanks.<br /><br />The engine is a Yamaha 150 HPDI.

 

[ianyoung77]

Re: Engine Cutting Out

Sounds like the overtemp sensor is telling the CDI to drop revs. Normally this operates a buzzer as well. You can short the sensor leads to check whether there is a buzzer or not.<br /><br />Assuming it is overtemp the normal remedy is to replace the impellor. This should be changed every year or so anyway

 

[ivar]

Re: Engine Cutting Out

I had a similar thing happen to my 92 Yamaha 60hp, <br />at low rpms it went fine, but after 5-10 minutes of running above 4000 rpm, it lost power and ran real rough. Sometimes it ran without a hitch too. <br />When it cut out, the engine would behave like that until it was completely cool. <br /><br />Turned out one of the coils had gone bad, probably shorting out as it got hot. Replacing it - everything fine.

 

[ntermini]

Re: Engine Cutting Out

How would I know if it is the impellor? I dont think there is a buzzer, I have never heard it. So could it still be the over temp sensor?<br /><br />Whats the cost for the coils or the impellor?

 

[ianyoung77]

Re: Engine Cutting Out

The impellor is part of the water pump in the lower part of the motor above the gearbox. If you haven't done it recently you should do it anyway. It will only cost about $20. Get a manual and give it a go. You can also search this site for other posts

 

[rodbolt]

Re: Engine Cutting Out

dude your motor is most likly fuel starved<br /> check the VST and the medium pressure filters<br /> if its an overtemp or an oil alarm you will have a visual indicate and a steady tone on the buzzer with a RPM reduction to about 2500 RPM. the water pump kit is about 50 dollars at the dealer. if you need aa pump you also need to service the pressure valve grommet and t-stats.<br /> dont do just the impeller. lots more to the pump than just the impeller.when was the last 200HR/annual service done. 2 100 HR services wont add up to one 100 hour service and remember the schedule is 200 hours OR annually whiever occurs first. not run it till it dies and fix it. you can verify fuel with a medium pressure fuel gauge and a lap top. the laptop can monitor high pressure fuel. but usually its the VST and the medium pressure filter combined with the low pressure pumps need periodic replacement.

 

[ntermini]

Re: Engine Cutting Out

I didnt get the engine serviced last year, so this just started recently. For the last 5 years I have had the engine serviced every year except for this year. The engine itself did not get 200 hours of usage last year. I talked to the mechanic and he thinks its something small like the fuel filter. I am also going to have him change the impellor.

 

[us010144]

Re: Engine Cutting Out

Could be fuel pumps, I am having sam problem 2001 150 hpdi's but no solution yet. runs fine, but then bogs under increased throttle or when I hit waves. If u fix it pls let me know, will do the same. thx

 

[rodbolt]

Re: Engine Cutting Out

ok<br /> what gauges are you running? and what year is it<br /> and what routine services have been done?

 

[us010144]

Re: Engine Cutting Out

twin 2001 hpdi 150's, with fuel management system, no alarms, has twin fuel tanks and fuel water separators, I have swithed them back and forth and don't think it's bad fuel. basic fogging/winterizing, just started ring-free after problem began. Just had it in with yamaha service dealer who said they found no errors with the computer....appreciate your help!