Re: 1961 Johnson 40 horse thermostat
Hiya & welcome,<br /><br />From your description, I can't really tell where the water is running out / exiting when you have it running (or if any is at all).<br /><br />Others will be along that know a lot more than me, but... there isn't really a "pee hole", tell-tale, water-flow indicator or whatever you wanna call it on those years of OMC motors. (nor on my 1970). Exhaust water mixture should come out of the relief hole that is on the back of leg about 1/2 way down. At higher speeds most exhaust is sucked out of the lower opening (behind the prop). You know your water pump is working if at idle, water sputters out of the hole 1/2 down the leg... should be lots of water coming out when running faster.<br /><br />Are you running it on a hose, or in a barrel? If in a tank/barrel, make sure the depth of the water is about the same as it would be when sitting on the boat. Otherwise the water pump has to suck water from down low. That's what it normally does when the boat's on plane, but at idle the pump might not do that well. I prefer using a barrel/garbage can, 'cause you can tell what the pump's doing without having the water pressure from the hose.<br /><br />If the motor is new-to-you, you'd be wise to service the water pump anyway. Who knows when it was last done. I've changed impellers in ones that I thought were working OK, and found the new impeller pumped WAY more water. It's a wear item, and way easier/cheaper than doing a motor rebuild from a bad overheat!<br /><br />anyway, that's my $.02<br /><br />Brent
