How many drain plugs on Mercruiser 502 MAG MPI?
#2
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From: Georgetown, TX
Should only be two places that actually drain the water from the block, one on each side in the middle. One likely has a flared hose fitting for water pressure and the other a petcock or actual plug you can remove.
#3
And a special note to the OP, make sure you run a zip tie / coat hanger / piece of wire into the openings after you pull the plugs - particularly the block drains. Sediment will occasionally plug the openings even after you pull the plugs.
#6
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From: Ray Twp. Michigan
#7
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From: Georgetown, TX
Originally Posted by griswald
Should only be two places that actually drain the water from the block
Last edited by Griswald; 12-05-2011 at 08:01 AM.
#9
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The year you have is the cool fuel system, Had you had an older non cool fuel system you still would have had 5, but the 5'th one would have been in the power steering cooler with a brass plug.





