Mercury 500 Overheating and stalling out

mdawg48331

Cadet
Joined
Jul 5, 2006
Messages
7
Ive got a simple question, but in that I didnt grab the S/N off my boat this may be harder...

I have a Mercury 500 outboard motor that has been overheating and stalling out. The boat sat out of the water for about 6 years waiting for me to replace the deck boards.. well now it does this to me. All signs lead to the waterpump, as I found that it wasnt shooting water out the jet on the side and I cannot tell if it is circulating correctly as I really dont know much about this motor.

I hooked up the hose to the inlet and got the motor to squirt out of the jet, but when I tried it without the hose connected it only worked once, then didnt work any other time I tried. Waterpump?... If so, anybody know what parts I would need to replace in able to get to the waterpump, or even a website with any type of help. Any info would be very helpful
 

PuckHog

Seaman
Joined
Jun 26, 2005
Messages
68
Re: Mercury 500 Overheating and stalling out

Ouch. It can take only minutes sometimes to overheat an gall a cylinder. First thing you'll need is a manual that covers your model. Then, at the very least you'll need an impeller kit (with requisite seals) and perhaps a new housing. Impeller life span is generally considered to be two years at the outside. First time replacing one will be occasionally frustrating, but very do-able. Check compression as well to see if any internal damage has occurred due too the over heating.
 
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