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Reply With QuoteMercs use the serial number for looking up parts. What makes you think the primer bulb is loosing prime? Symptoms?
Crappie Wall Hanger II
Service to 1998 Mercury 75
Hi Everyone,
I want to replace the water pump on my entitled motor. How do I know that I've ordered the correct part/kit? She is pumping good now, but it's been a several years since it was done.
Also, the primer ball will not stay primed after not running for three to four hours. I've changed the bulb, but that did not fix it. I've read that it's probably the fuel pump diaphragm, but again, how do I know I've ordered the correct parts.
Besides plugs, is there anything else that I should replace while I have her out of the water?
Thanks!
Ed
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Mercs use the serial number for looking up parts. What makes you think the primer bulb is loosing prime? Symptoms?
Fair Winds and Following Seas
Bill H. PTC USN Ret
Chesapeake, Va
Crappie.com 2019 Man of Year, Supermod & Moderator of the Mechanics Forum
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Go to this page and find your model number. Then it will pull up a page with different sections of parts. Like bill said some places also use serial number, but I have found this site easiest to navigate for someone not used to searching for parts. If you have problems just post up and one of us will help you out.
1998 Mercury 75HP Outboard Parts | Boats.net
Proud Member of Team Geezer
Charlie Weaver USN/ENC 1965-1979
Slabmaster
you might have a checkvalve in between gas tank and the primer that is the trouble. gary
Crappie Wall Hanger II
Thanks Everyone. Cray, I will check out that site and let you know of any issues. Very much appreciated.
As for why I think this, I start the day with ensuring the bulb is primed. From there, engine starts and runs perfect. After fishing for three to four hours, and I don't re-prime the bulp, as I'm running (not running hard), the engine will start to lose power, and then dies. I go back, re-prime the bulb, and she takes back off with no issue.
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I had a 84 model 50 hp Merc that did that...It was the fuel pump diaphram.
I have spent most my life fishing........the rest I wasted.
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when you changed Bulb did you change Fuel line too ???? or just the Bulb ??? if you change only the Bulb your issue could be Fuel line !!!! I had a 1996 75hp Mercury and it did very same thing you are describing and it was the fuel deteriorating internally clogging up at the fitting going to the motor !!! changed bulb and fuel line never had another issue !!!!Originally Posted by KokomoTerror
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On a 98 model motor....if you never have....you should replace every fuel line on it....not just the bulb.
I have spent most my life fishing........the rest I wasted.
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Crappie Wall Hanger II
Thanks guys! Yes, fuel line was replaced at the same time the bulb was replaced.
strmwalker LIKED above post
Crappie Wall Hanger II
I replaced my old, cracking primer bulb, and just a couple of years later I was not happy with it. It would prime up, I could ride down the river to where I wanted to go, stop and fish a while, then my motor would not want to start back up unless I went back there and primed it again sometimes. To me, the bulb just did not feel quite right. In Walmart, I bought an Attwood Bulb, that claimed 30% greater capacity, (for what it's worth).
At home, when I removed my 2 year old bulb, I held my little finger and thumb over the ends, and squeezed it several times and noticed a mushy feeling about it. It was like the bladder was separating or tearing up inside of it. Something was just not right. The Attwood Bulb was really firm to that same test, and felt solid. I installed it, and all has been well, never a problem.
This may not be your problem, just sharing what fixed mine. My two year old bulb was absolutely loosing prime.
