2006 Optimax 150 Surging at 3000 RPM

[jeffersondodson561]

Re: 2006 Optimax 150 Surging at 3000 RPM

Here is a picture of the fuel pressure regulator and its description.

 

[spilman]

Re: 2006 Optimax 150 Surging at 3000 RPM

Thanks Jeff

 

[omb]

Re: 2006 Optimax 150 Surging at 3000 RPM

It's fun.....................................I works as a mekaniker on outboards. I have an engine with 100% same error, it is a 150 optimax 1999.I have not found the bug yet. but I do not think there is enough gas in the high pressure pump.I return when I have found the error.
it gives me gray hair.

 

[spilman]

Re: 2006 Optimax 150 Surging at 3000 RPM

We think we have found the problem. The plastic connector that the high speed pump plugs into was bad. Making eratic contact. I had the same problem with the fuse block. Sometime power and sometimes not. Tha bad connections was causing the high speed pump in the VST to drop out and thus the reduction in fuel pressure. I recommend checking all plugs very carefully.

 

[omb]

Re: 2006 Optimax 150 Surging at 3000 RPM

I found the error on the engine today.There was no pressure from the low pressure pump (electric).then the high pressure pump drawing fuel through the small hole in VST #9 ,it works fine as long as fuel consumption is low.but above 3000 rpm it can not deliver enough fuel and the pressure decreases. then the engine shall back to idle until it has filled the system up again.I still believe that your engine is missing fuel.try to measure the pressure at low pressure pump.