Fuel Pump Pressure

[FreeBeeTony]

Checked fuel pump pressure again last night.<br />~5-6lbs at idle in neutral.<br />When under load the needle was bouncing betwee. 0-~8lbs. I held the gauge in my hand, I don't think it was from vibration. The full scale of the gauge was probably about 80lbs (working from memory here), so I was only reading a small portion of the gauge. But I don't think the reading should have been bouncing that much.<br /><br />I am hoping I am on to something here........<br /><br />I haven't been able to pull the boat out yet to check for the exhaust restriction.<br /><br />Anybody ever use a Sierra pump?

 

[Bondo]

Re: Fuel Pump Pressure

I am hoping I am on to something here........

Me Too................... <br /><br />An 80lb gage isn't My 1st choice,...1 with a 20lb. scale would no doubt be Better for fuel pressure,..........<br /> But you gotta do what you can with what you've got............<br /><br />Your fuel pressure should read the Same at WOT as you're getting at Idle........ 5/6psi....Steadily,...Solidly......<br /><br />I've never had Any Problems with Sierra parts,....<br />But,... Everybody makes Bad Parts,.... Sometimes....... Might even have some "Junk" inside it.........

 

[FreeBeeTony]

Re: Fuel Pump Pressure

So bondo........that doesn't seem right to you?<br />It was definitly not steady or solidly!

 

[FreeBeeTony]

Re: Fuel Pump Pressure

Remeasured pressure with a 15lb gauge. Pressure started ~10 at idle and went to ~8 at higher RPM's. Is this too high?<br /><br />May have a redundant post here............sorry.

 

[Buttanic]

Re: Fuel Pump Pressure

If your gauge is accurate, 10 psi at idle is high and 8 under load is high. I feel 10 at idle might push fuel by the float valve in the carburator and cause a rich idle. Is it a new gauge and can you check it with a similar one. Like Bondo said 5 to 6 and steady.

 

[FreeBeeTony]

Re: Fuel Pump Pressure

It's a brand new gauge..........really have no way of calibrating it.

 

[Bondo]

Re: Fuel Pump Pressure

If that gage Is right,..........<br /><br />Your Plugs should be Black,+ Carbon Caked........<br />8/10lbs. is Way High.........Was it Steady at all rpms ??<br /><br />Without going back thru these posts,.......<br />What Do your plugs look like,..???