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Mercury 500

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  • Mercury 500

    Would anyone be able to tell me the year of my 50 hp Mercury? As far as model goes, I believe it is a Mercury 500 and has Super Thunderbolt stamped in the block. The serial number is C3243721. As well I am having a problem with it that seems to occur intermittently. Sometimes when at full throttle it just suddenly drops to a crawl without having touched the throttle. It still remain running and when returned to neutral and then dropped back into full throttle, it jumps right back up to plane for some time until (if) it happens again. Throttle control? Cables? Ideas?

  • #2
    Re: Mercury 500

    C221500-D000749= 1990 YR. 3CYL.


    • #3
      Re: Mercury 500

      Thanks for the input Rex, but it's a 4 cylinder and definitely appears a bit older than 1990 (unfortunately...)The cowling is silver with a blue stripe. I have tried a couple of sites including the pfs-ware site, and another that was posted in a previous conversation, to look up my serial number, but have come up scratching my head. Any other ideas out there?


      • #4
        Re: Mercury 500

        Yeah, your Merc 500 is about same vintage as mine, 72-74 as best as I can remember, serial numbers are pretty close. If you want exact year go to mercurymarine.com and hit the manuals link. You have to call and talk to a little old lady who will tell you what year and offer to sell you a manual for mucho deniro. Ebay is a better bet in my opinion. Watch for service manuals there. No idea why your engine is grunting out. Keep trying here or go to www.pfs-ware.com, and then the Q&A page on the old Merc site. I find good stuff there about out engines/motors.


        • #5
          Re: Mercury 500

          Thanks for the input Tim! I will try the mercury marine site, I was trying to narrow the year down to as close as I could get. If anyone has any ideas concerning the abrupt change in pace I experience on an irregular basis, please lend me your knowledge.


          • #6
            Re: Mercury 500

            It is a 1972.500 (50,0) 3235063 - 3478002 1972 4 cyl http://www.marinshopen.se/guide/mp/merc65.htm /Bear


            • #7
              Re: Mercury 500

              Thanks Bear! This gives me something to work with!