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4 hp mercury

jimmbo

New member
hi i bought a used 4 hp mercury shortshaft.seriel#9313527.im trying to find out what year it is and were the water should squirt out.i cleaned the carb and have it running nicely in a pale of water but i dont see any water comeing out of the power head.when purchased the previous owner gave me some receipts saying the water pump and housing were replaced in 2008.im looking for any info on this unit i can find.it also has a thunderbolt ignition.thanks,jim
 
That is a 1979 Belgian built (Merc Belgium) motor. The 4 horse was produced exclusively at that plant during that period (so no US models at all).

This should be one of the little twin cylinder jobs that did not have a "tell tale".

While I don't remember the exact location, there are one or two "exhaust relief holes" on the back of the leg (look a couple inches below the lower cowl, on the back of the leg (facing the prop)).

These will kinda "spit" or "weep" water if all is well.

It's kinda a sucky system (have the same thing on my 2.5 twin Evinrude), but that's all you got....
 
hey thanks a lot galamb,it does say made in belgian and i found the two little weep holes.and it is a little twin jobby.were can i find a diagram or a parts picture of this thing?id like to know what this thing looks like on the inside.how will i know if this thing is heating up?i want to try it out soon but i dont want to kill it.anyway, youve been a big help.thanks again jim.
 
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I will run the serial number and I can probably print off the parts list for ya and mail it out for the price of postage if that helps. I have a bunch of parts for those motors as well. Swivel, Carb, etc...

rgds,
 
ok thanks again guys.i can make most gas engines run but ive never mest with marine engines.i bought a 14 ft outchita jon boat.its old but in really nice shape.just wright for me and my kids.im still curious what are some signs of over heating?maybe im over thinking this,i know i can run my husky chain saw for hours and hours running it out of gas at the end of each tank full for a year or two with no problem but i dont know outboards.anyway thanks a million.jim
 
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