HI I have a 1951 evinrude 25hp I just got it running<br />but it over heated I think the termastat is stuck.<br />can some one please tell we where it is and how to get it out thanks.
Hello what?<br /><br />Your engine does not have a thermostat. It's far more likely that the water pump's impeller has fallen apart. If you don't know it's less than 2 years old, it's time to replace it.<br /><br />Water should come gushing out from the large hole on the back of the exhaust leg. The hole is about 1" in diameter, and has a couple smaller holes drilled in it.<br /><br />The impeller is sitting on top of the lower unit, so it is where the lower unit mounts to the exhaust leg. A manual will show you how to change it. <br /><br />Impeller is Sierra 18-3006, available at NAPA autoparts stores from their marine catalog, if you're in the US. If not, iboats has it here. $12.
What66, try, when running, to stick a paper clip or something small into the pee hole, or check the intake on the lower unit. Salt crstals(if on the ocean) can form, or you may have sucked up something that may be clogging your intake. An easy fix! But, of course,most of the time, not much is that easy on and outboard! Good Luck!
Doubtful a 51' will have a pee hole seconddraw. I think Rick got it, change out the impeller. Try the link below for a service manual what66. I did a search and it said they gottem'.<br /><br /> http://ww3.kencook.com/evinrudejohnsonmanuals/ <br /><br />Keep us posted and don't hesitate to ask questions....thanks.
What66,<br />One more thing, see if you can hookup a garden hose with short piece of rubber hose to the water pickup tube. Turn on water and make sure water can circulate thru the powerhead before you replace the impeller. <br />After replacing the impeller, if you still have an overheat, you'll know it's not due to a blockage in the powerhead.
That would make a whole lot more sense if you were looking at it. <br /><br />They're the exhaust relief holes, and they're drilled through the sidewall of the 1" water outlet hole. And it's actually closer to 3/4" dia than 1".
