Yamaha Water Pressure??

[outraged]

1987 115 hp Yamaha. Two seasons ago replaced impeller, Idled @5 psi Cruised @ 24 psi. Replaced impeller, tank tested currently idles @ 14 psi needle passes gauge max of 30 psi @ 2900 rpm's. Impellers looked to be identical upon replacement. Is there a normal operating range? Gauge was replaced three years ago, telltale looks like a pressure washer.

 

[Capt Ken]

Re: Yamaha Water Pressure??

Nope, no normal range but I would check the pressure relief valve at the lower right side of the exhaust housing to be sure it isn't sticking. If everything looks good, let it ride.

 

[outraged]

Re: Yamaha Water Pressure??

Thanks Ken, I'll check it out. Due to age of motor & its saltwater use, my concern is internal corrosion reducing flow with an increase in pressure. I ran it for 15 mins. @ 2000 rpms, no overheat alarm, head temps about 140*. I guess all is well?

 

[outraged]

Re: Yamaha Water Pressure??

Thanks for your help Ken, finally had time to check this out & replaced bypass valve, pressure is back to normal. My only concern is the neoprene grommet got away from me & fell into exhaust cover. How serious is this?