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Click for Crusader parts and manuals!
Results 1 to 15 of 15
  1. #1
    Join Date
    Aug 2006
    Location
    Lakeville, IN, USA
    Posts
    198

    Default "The shop manual for my 8.2s M

    "The shop manual for my 8.2s MPI engines says that the fuel system should retain pressure for about 30 seconds after the fuel pump shuts down. Mine go to 0 immediately after the pump shuts down. I followed the troubleshooting guide to determine if the leak is at the pump, the injectors or the pressure regulator and determined it was at the regulator. Replaced the regulator as the manual said it was defective, and even with the new regulator it still goes to 0 right after the pump shuts down. The gentleman at Crusader says do not worry about it but the Crusader shop manual says I have something wrong... any ideas?"

  2. #2
    Join Date
    Sep 2006
    Location
    SF BAY AREA, CALI, USA
    Posts
    8,641

    Default any motor problems??

    any motor problems??
    HUMAN BUILT = HUMAN FIXED

    CERTIFIED MARINE TECHNICIAN

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  3. #3
    Join Date
    Aug 2006
    Location
    Lakeville, IN, USA
    Posts
    198

    Default "That is a darn good question.

    "That is a darn good question. I have been chasing a rough-low idle issue in my starboard engine for two seasons and am at my wits end, I have started going back over everything to see if I missed anything, my fuel pressure at the rail on the starboard engine is @ 38 psi at idle, port eng. is 43 psi. Port engine runs fine. But neither engine holds fuel pressure after the pump shuts down like the manual says it should. I specifically bought the shop manuals (thru this site) so I could try to avoid having to deal with a multitude of very expensive mechanics throwing parts at my engine without any tangible results. I have almost replaced everything externally on that engine chasing down this gremlin,I have been in contact with Greg Messenger at Crusader who has been extremely helpful, at his invite I sent my ECMS for both engines in this spring for recalibration, and that really helped at least in the beginning, by the end of the season the engine was really running poorly at idle, it would stall when I would put it in gear while manuvering it into the slip,(thats not fun) the idle would surge, etc. Runs fine at anything above idle. Gregs last suggestion was to send the ECMS back to bump up the idle... I did not do that yet as I feel if the port engine runs good at 650 rpm why can't the starboard??? Part of my problem now is How much can I rely on these shop manuals for troubleshooting? The troubleshooting chart for the fuel system clearly says that under my circumstances my fuel pressure regulator is defective... ??? Greg says do not worry about it. I have no reason not to trust him, but it is really confusing."

  4. #4
    Join Date
    Sep 2006
    Location
    SF BAY AREA, CALI, USA
    Posts
    8,641

    Default you have mefi 4 right?

    you have mefi 4 right?
    HUMAN BUILT = HUMAN FIXED

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    WWW.SWITCHBAIT.COM

  5. #5
    Join Date
    Aug 2006
    Location
    Lakeville, IN, USA
    Posts
    198

    Default I am not sure which version of

    I am not sure which version of MEFI it is off the top of my head. According to the serial numbers (which are sequential interestingly) the engines were built in 1998. Does that help? I THINK it is 3 but I dont have access to all of my notes and manuals right now.

  6. #6
    Join Date
    Sep 2003
    Location
    New Tripoli, PA, USA!
    Posts
    12,506

    Default "Had a car that did that--the

    "Had a car that did that--the injectors were leaking down. Made hot restart a problem, but cold starting the next morning was uneffected.

    Jeff"

  7. #7
    Join Date
    Aug 2006
    Location
    Lakeville, IN, USA
    Posts
    198

    Default "When I blocked the fuel retur

    "When I blocked the fuel return line the pressure held, which according to the manual meant that the injector(s) were not leaking."

  8. #8
    Join Date
    Sep 2006
    Location
    SF BAY AREA, CALI, USA
    Posts
    8,641

    Default mefi 3 that is e-z to diagnos

    mefi 3
    that is e-z to diagnosis

    what manuals u got??
    HUMAN BUILT = HUMAN FIXED

    CERTIFIED MARINE TECHNICIAN

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  9. #9
    Join Date
    Nov 2002
    Location
    Mullica Hill, New Jersey, United States
    Posts
    1,810

    Default I've only ever seen this w

    I've only ever seen this with a bad fuel pump.

  10. #10
    Join Date
    Aug 2006
    Location
    Lakeville, IN, USA
    Posts
    198

    Default "I have the XL Engine manual a

    "I have the XL Engine manual and I also have the manual which specifically deals with the MEFI 3 diagnostics which includes all of the info on the fuel injection system, ECMs, trouble codes and the like. It is that manual that is telling me based on my symptoms that I have bad fuel pressure regulators.
    Rick, a new fuel pump has been one of the many things I replaced. Prior to replacement fuel psi was @ 5 psi less than port engine, 38 vs 43 at idle, but the gauge needle fluctuated where the port was rock steady. Put new pump in, pressure never increased but needle steadied. I have no idea if that means anything."

  11. #11
    Join Date
    Sep 2006
    Location
    SF BAY AREA, CALI, USA
    Posts
    8,641

    Default u have a water separator on th

    u have a water separator on the boat?
    HUMAN BUILT = HUMAN FIXED

    CERTIFIED MARINE TECHNICIAN

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  12. #12
    Join Date
    Nov 2002
    Location
    Mullica Hill, New Jersey, United States
    Posts
    1,810

    Default "Scott, It means that the c

    "Scott,

    It means that the check valve in the pump was not seating properly. I have seen this same thing cause the pressure to drop immediately, once the pump stops running."

  13. #13
    Join Date
    Aug 2006
    Location
    Lakeville, IN, USA
    Posts
    198

    Default "Yes I have a Racor water sepa

    "Yes I have a Racor water separating filter unit which is secondary to a washable fine mesh screen filter.
    Rick, the weird thing is that the pressure drop still occurs after replacing the pump with a new pump. I was wondering if there could be a voltage issue to the pump that may cause the lower pressure??? Also the pressure drop still occurs in the starboard engine even after a new pump and a new pressure regulator, and AFTER doing the test to be sure the injectors were not the culprits... so, where in the heck is the pressure going to???"

  14. #14
    Join Date
    Nov 2002
    Location
    Mullica Hill, New Jersey, United States
    Posts
    1,810

    Default "Scott, The way this system

    "Scott,

    The way this system works is that the pump supplies constant fuel to the fuel rail. Once the fuel reaches the desired pressure, the regulator opens, allowing fuel into the return system. Take a vacuum reading on the line going to the regulator. A low reading may explain the low fuel pressure, it may also indicate another problem."

  15. #15
    Join Date
    Aug 2006
    Location
    Lakeville, IN, USA
    Posts
    198

    Default "What numbers should I be look

    "What numbers should I be looking for as far as vacuum? Test at idle? Unfortunately the boat is on the hard and I will have to wait until the spring to check. What other problems could it indicate?
    But,shouldn't the regulator be closed when the engine is off and there is no vacuum? If so then why does my pressure drop immediately when the pump shuts down? (engine off) It has to be blowing right through the regulator, right? Manual says "replace defective regulator" , Crusader tech says "don't worry about it", I replaced the regulator because I bought new one before Crusader said "dont worry about it" and it still does it even with new regulator."

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