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PCM 5.7 Fuel Issue at higher RPM

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Bertram28

New member
All,

I recently bought a Bertram 28 with PCM 330hp(?) MPI 5.7 engines that were put in in 2008. They have about 140 hours on them. I am having issues with the stbd (and now both)- after running for around an hour, they start cutting out while on plane. The fuel control cell and low pressure pumps are warm to the touch when this happens. I have had my mechanic replace one low pressure pump on that stbd engine (twice actually- thinking this was the issue and that maybe they sent us a bad pump) and switched the FCC from the problematic engine to the other and the same thing happened on the same engine with the swapped FCC. I have replaced fuel/water separators numerous times (the boat sat up for about a year when I bought it) and have drawn from different tanks and it still happens. The port engine had no issues until this weekend, and now it is doing the same thing- off a different tank. Anyone have any ideas? I am $1000 into mechanic bills and have gotten nowhere. Could it be fuel lines? Any ideas? Thanks!

Ben in Orange Beach, AL
 
What are the fuel tanks made of?

Has the mechanic been allowed to do his job - diagnose the problem - or is this a 'throw parts at the problem' approach?

I'd be incline to decide the fuel-ignition problem first....and a code scan would be a prudent step that way.
 
The main tank is fiberglass (I have been running non-ethanol fuel)- the aux tanks are aluminum. It doesn't seem to matter which tanks I source to. I did take her out yesterday for an hour and the port engine ran fine (fuel cell was cool) and the stbd engine ran fine but the fuel cell was warming up. Just before the engines cut out at cruise, one can hear a shreaking sound like they are being starved of fuel.

He hooked his laptop up to it a few weeks back but it didn't seem to show anything abnormal- he said that it wouldn't show a fuel issue. I do feel like we are throwing parts at it. I bought all new fuel line today and am going to replace them. I also replaced the fuel/water separators again. I plan to run her for a couple of hours then. Thanks!
 
Good on the non-ethanol fuel source...hope it remains viable.

I'd be inclined to hook up a fuel pressure gauge on the rails and watch it. It needs to supply minimum pressure across the whole RPM band. If you can see the pressure drop then you know it's a fuel issue. Being as the pumps have been changed, I'd suspect a fuel supply issue or a pump control issue.

Since the issue appears to be independent of the tank (source), you may want to verify the integrity of the plumbing, from the tanks to the pumps. You can install a vacuum gauge on the suction side and make sure the pump creates suction all the time it is running.

The pump control problem could be a bad sensor or switch. Some OEMs make use of the ECU for this but many don't (no trouble codes). The easiest way to find these is to hook a test light to the DC supply feeding the pump, right at the pump. If the light dims or goes out, and the connections to the light are secure, the oil pressure control device is a possible candidate (non-ECU controlled pumps). Fuel pump relays are also possible suspects. ECU controlled pumps should have a "PID" that can be monitored (sensor input used to control the pump).
 
I did switch fuel lines and return lines between port and stbd engines (all going to main tank) and problem still occurred. I did find that my engines are 2005 model PCM PXRA (or PXLA?) WR 000M engines. I believe they are Excaliburs, 330 hp 5.7.
 
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