High Fuel Pressure

badrano

Petty Officer 1st Class
Joined
Aug 7, 2018
Messages
354
I've been running rich and did a pressure check and I'm running about 70psi at idle.
Trying to get a couple questions answered so I can just hop from one thing to another to get me through the diagnostics.

Last season I got the fuel injectors cleaned which apparently they needed it. 2 of the 8 had a poor spray pattern. At the time I had checked fuel pressure and it seemed ok but never to did get out to check it with the engine under load. For the rest of last season, everything seemed ok.

I've only used the boat about 4-5 times since May this year and the rich condition became more noticeable yesterday as it almost stalled out on me at idle and my fuel usage for the trip I took seem unusually high. When I got back to the ramp, she was smoking pretty good.

My next step is to check vacuum. If that's is ok, I'm going to assume I have a pressure regulator issue. I realized I have 2 regulators.... one on the rail and one on the cool fuel 3 module. How do you determine which regulator is the issue? Should I just replace both? This is a 20 year old boat.
Looking closer at the fuel module, it looks like I could get the regulator off using a wrench (no real room for a socket, especially for the bolt that's right under the edge of the exh manifold). But then how can I make sure I've torqued the bolts back down afterwards? Do I have to consider pulling the fuel module off?
I understand that my serial number falls into the range of the service bulletin for the paint issue on the cool fuel 3 modules.

Any other advice/guidance to resolve the high fuel pressure?
 

alldodge

Moderator
Staff member
Joined
Mar 8, 2009
Messages
43,144
The Reg on the rail does not actually regulate pressure, it's there as a damper, it try's to reduce the pulses coming from the fuel pump.

Make sure the Reg on the fuel module is not clogged up. It needs to be able to return over pressure back to low side of pump module. Needs a good cleaning
 
Top