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  1. #11

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    Quote Originally Posted by radio-active View Post
    Mine were failing identically. They apparently have a molding flaw.

    I went to the auto parts store and bought 9" black bungee straps. I removed the hooks, folded them over and used them in place of the originals. I may have opened the holes up a bit with a drill.
    sounds like an easy way to replace them. The lower straps seem fine.


  2. #12
    radio-active's Avatar
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    Check it, I can pretty much guarantee it'll be starting to fatigue at the same spot. The bungees are cheap and sturdier than the originals.

  3. #13

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    Fixed the fuel pressure regulator, put it all back together, still no fuel pressure…

    I’m going to try another fuel pressure gauge first but it looks like I’ll probably be taking it apart again. I’ll start by bench testing the fuel pump while it’s still in the tank. I should be able to do the same with the fuel pressure regulator by putting air pressure to it. At this point I’ll probably put new fuel lines on it too. It’s a good thing winter lasts nine months here in upstate NY. I think I’ll need the time.

  4. #14
    Moderator HiPeRcO's Avatar
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    Quote Originally Posted by allyolds68 View Post
    Fixed the fuel pressure regulator, put it all back together, still no fuel pressure…

    I’m going to try another fuel pressure gauge first but it looks like I’ll probably be taking it apart again. I’ll start by bench testing the fuel pump while it’s still in the tank. I should be able to do the same with the fuel pressure regulator by putting air pressure to it. At this point I’ll probably put new fuel lines on it too. It’s a good thing winter lasts nine months here in upstate NY. I think I’ll need the time.
    Is the pump turning on? Ground the brown wire.

    Often the Schrader valve core sits too low to get pressed down by the fuel gauge. You can remove the core for the test.

  5. #15

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    Quote Originally Posted by HiPeRcO View Post
    Is the pump turning on? Ground the brown wire.

    Often the Schrader valve core sits too low to get pressed down by the fuel gauge. You can remove the core for the test.
    The motor's running so I assume the fuel pump is working. I only ran it for about 5-10 seconds at a time. The RPM's come up normally but obviously it isn't under load so it doesn't mean much. In my somewhat limited experience with my Mustang's EFI system a fuel pump either works or it doesn't. Low battery voltage also effects fuel pump output but I assume that since it runs the fuel injectors are working and they are more dependent on good voltage than the pump. When my alternator was shot in my Mustang the engine had no power and would hardly idle. It had fuel pressure but it was very low.

    The fuel pressure gauge could definitely be the problem as it's a cheap HF unit although I did crack the schrader while it was running and I get a steady stream of gas but it doesn't seem like it's as strong as it should be. 20+ psi should be more than a steady stream 6" or so high. (totally a guess and not very scientific....lol).

    As much of a PIA it is to drain the oil and fuel tank and pull everything out, I think it's going to happen again. At least I've done it now so it should take half the time. This will actually be the third time as I had the pump pick-up clocked 90 degrees off the first time and the fuel tank float wasn't facing forward. Fortunately I noticed it before putting the steering back together the last time.

    Before I do anything else I'm going to back it into the water and test the TPS. They're drawing the lake down now and I won't be able to test it under load soon.
    Last edited by allyolds68; 10-15-2021 at 07:28 AM.

  6. #16
    Click avatar for tech links/info K447's Avatar
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    Quote Originally Posted by allyolds68 View Post
    ..; a fuel pump either works or it doesn't. Low battery voltage also effects fuel pump output but I assume that since it runs the fuel injectors are working and they are more dependent on good voltage than the pump.

    ...
    A Ficht fuel pump can run and provide ‘some’ pressure but have a clogged inlet or simply be running slowly.

    Check the voltage on the Brown wire (relative to engine ground) while the engine is running. It should not be more than maybe 1 volt. A cold engine can be run for 20 seconds or so without water cooling.

    Beware of using automotive diagnostics with a Ficht system. Ficht is different.

    The Ficht fuel injectors have nothing to do with battery voltage (they run on 45 volts DC provided from the stator and EMM). The Ficht injectors are actually compact high pressure fuel pumps (several hundred PSI inside the injector) with integrated direct injection poppet nozzles, not just simple valves and spray nozzles as found in a traditional car fuel injector.

    The pressure and flow provided by the Ficht fuel pump is there to cool the injectors and to keep the internal injector RAM pulse fuel cavity flooded with liquid fuel.

  7. #17
    martincom's Avatar
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    Remove the large, 40-pin plug from the EMM. Identify pin 40, which has a brown wire terminated upon it. Ground pin 40, but be careful not to distort or scrape the plating from the pin receptacle with whatever you insert into it. You should hear the fuel pump run when you ground pin 40.

    If you don't, does it draw current (spark) when you ground it? I've had the pumps gum up from old gasoline and stick. Bumping the ground connection on/off repeatedly will some times free them. In extreme cases, I've had to isolate the pump electrically and alternate between forward and reverse polarity to free them.

    If the pressure is low or no pressure, but the pump is running, the pump intake screen is likely plugged from contaminants. See this thread for details.

    Now is also a good opportunity to measure the fuel pump current draw by inserting a current meter between the pin 40 contact and ground.

    An OEM pump will draw approximately 2.0 amps. Many of the so-called aftermarket direct replacements will draw excessive current, greater than 4.0 amps. This is more than the EMM can tolerate and it will shutdown the fuel pump driver.
    Last edited by K447; 10-15-2021 at 10:24 AM.

  8. #18

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    The voltage on the pump was around 0.5V. Darrin, you were correct, that the cheap HF fuel pressure gauge wasn’t depressing the schrader valve. When I removed the schrader I got 22 psi but….. the pressure came up very slowly. It probably took 20-30 seconds to build. I checked the voltage on the white TPS signal wire under load and I get 0.275V at idle and 4.05V at WOT.

    I did a quick run out from shore and it ran much better but still didn’t take off hard and it didn’t go over 5700 rpms. The PTO and Mag cylinders are hot to the touch (like I can’t hold my fingers on it for more than 5-10 seconds). The center cylinder is cold which leads me to believe that it’s not firing. I got a set of Champion QC10PEP’s delivered today. I’m going to check for spark on the center cylinder tomorrow.

    The lake is getting low so I won’t have much more time to check it under load this year.
    Last edited by allyolds68; 10-16-2021 at 06:40 PM.

  9. #19
    Click avatar for tech links/info K447's Avatar
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    Quote Originally Posted by allyolds68 View Post
    … I got 22 psi but….. the pressure came up very slowly. It probably took 20-30 seconds to build.

    I checked the voltage on the white TPS signal wire under load and I get 0.275V at idle and 4.05V at WOT.

    That TPS max voltage seems a tad low. So does the idle voltage. Is your TPS adjustable on the mounting bolts?

    Fuel pressure should jump up to full pressure within a couple of seconds, not 20 seconds.

  10. #20

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    Quote Originally Posted by K447 View Post
    That TPS max voltage seems a tad low. So does the idle voltage. Is your TPS adjustable on the mounting bolts?

    Fuel pressure should jump up to full pressure within a couple of seconds, not 20 seconds.
    I checked a few other things out of the water today. First I checked the fuel pressure again. An o-ring was restricting the fuel flow. I pulled it out and the pressure immediately jump to 22 psi running. Then I re-ran the compression and got the same results, 120psi across all three. The center plug was wet and black. I cleaned it before taking the pic below. The mag and pto were both ok. The injector voltage was 14.95V cranking and 45V running. Battery seems strong. I don’t know why the injector voltage is low.

    I loosened the TPS but it didn’t really seem to rotate much. I’m not going to mess with that for a while because I’m going to need a new throttle cable too. The plastic on the lower section was busted up. Those don’t seem hard to come by.
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