boat motor

[oxcowboy]

hi folks,

 

Getting ready for my big trip north, figured i better get my other motor out and run it a bit. Before i stored last fall, i did all the usual. got her out today put her in the tank and let her run for a while, started ok, a little rough, but then took off real nice, tried at all different idle speeds and was good, then i noticed that the water had quit spraying when i had it idled down real low. revved her up and then she started spraying for a while and then stopped again. took it out of the tank and could see bits of rubber at the vent screen. crap the old impeller has blown up on me. not being to mechanically inclined i start looking for somebody to work on it, after about 4 calls i get a guy and after i told him what was wrong, his first comment was "you didnt run it in a tank did ya?" of course i said yes and he goes on to tell me he fixes more water pumps from people running them in tanks than anything else. he said that the air bubbles the motor puts out is about the same as running one dry. I had never heard this before, i always thought it was safe to use a tank or barrel to run a motor. Anyway i got to learn a little something today, not sure how much it will cost me yet, hopefully not too much, its only a 4 hp merc.

 

So the moral to the story is Dont run your motor for very long in a tank. buy the muffs or put it on a boat in water.

 

 

jason

[Fisherman]

As long as there was some water getting through, there is no damage done. It's if you run it dry or nothing at all is coming out after a minute or so, then the motor will overheat and maybe seize. Changing an impeller on those is pretty easy, should be 4-5 bolts under the cavitation plate, and undoing the shift linkage, slide the lower unit off, take off the 2 bolts that hold the impeller cover on, slide it up off the driveshaft, pull out the old impeller and replace. It will be tight. Add a plop of vaseline, it will provide sufficient lube. re align everything and bolt back together. Might not hurt to blow compressed air backwards through the water outlet under the motor, it might remove some old chunks of the old rubber. It probably wouldn't hurt to smear the splined end of the driveshaft with some anti seize before replacing. Some carbon up so bad, they won't come apart without a real beating, Good luck.