Mechanical fuel pump issue

Discussion in 'General Maintenance/Repair Questions' started by JimmyDubai, May 19, 2017.

  1. JimmyDubai

    JimmyDubai Member SILVER Sponsor

    282
    Oct 13, 2015
    Dubai, UAE
    As above, 1996, one big block Mercruiser 7.4 LT
    Simrad Go9 XSE + 3G radar
    One, Mercruiser 7.4 V8, 310 HP
    Hi, The boat went for service ( Mercruiser 7.4 Lt V-8 carb) and the raw seawater pump was replaced among other things. We went for a ride and on the way back we noticed a squeaky noise coming from the engine. A few more nautical miles and the engine quit.

    This morning I went to the marina and managed to remove the fuel pump. The questions below will show you the findings:

    - Can you possibly move the lever with your own hands? I found it very stiff to move! Actually it looks like that lever is stuck
    - On the engine side I found a bushing that moves freely with a play of I guess 1/32" (or less than 1 mm) which is the part that is always in contact with the lever. That part was completely dry, no oil, no water, nothing, the contact was metal to metal. I could see as well that there is a play of maybe 1/32 or less than 1 mm between the bushing and the shaft. My question is: how is the lubrication in this part? To me the squeaky noise that I heard was coming right from these three parts (shaft, bushing and lever dead dry).

    Could potentially the replacement of the sea water impeller be the cause due to a wrong procedure? remember that all these items are part of the same thing (pulley, V-belt, eccentric fuel pump shaft, fuel pump, raw seawater impeller shaft and plastic body.

    Your comments please?

    Thanks
     
  2. Bt Doctur

    Bt Doctur Active Member

    Aug 21, 2010
    New Jersey
    Ex SRV 240 Weekender twin
    in between
    sound like no oil was added after the repair and you should be able to move the fuel pump arm , palm of hand and push
    From manual 15 [​IMG]
     
  3. JimmyDubai

    JimmyDubai Member SILVER Sponsor

    282
    Oct 13, 2015
    Dubai, UAE
    As above, 1996, one big block Mercruiser 7.4 LT
    Simrad Go9 XSE + 3G radar
    One, Mercruiser 7.4 V8, 310 HP
    Exactly the information I was looking for; serious conversation with the mechanic tomorrow!! Many thanks


    Sent from my iPhone using Tapatalk
     

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