Hi guys, new to the site and new to boating. My wife's grandfather gave us his 1964 15' Uniflite with a 1965 Evinrude Big Twin 40552S E01240. Everything looked in good shape despite it sitting for about 8yrs from last time he took it out although he said he started it every once in a while. I know it hasn't ran for a long time cause the gas was not drained and the gas in the bowl was bad. Plugs were clean, hoses looked good and everything else also looked good, he did recommend changing the impeller as it's been sitting for awhile. So I changed the lower unit oil and I changed the impeller, housing and grommets. Engine started up right away and ran really good after a couple start ups.
My question is, I wasn't getting the tell tale water coming out, but you could see air (not steam) coming out of the hole. I took the water pump apart a couple times thinking I missed something but both times everything was good. After searching for ideas in the forums I took out the thermostat and ran the motor without it. Now I get good water coming out the hole right away. Put the stat back in and no water so I kept running it keeping an eye on the engine temp with a digital temp gun and once it gets warm after a couple of minutes I see some steam and water coming out at about 115 degrees engine temp. Engine running great.
Is this steam normal? I've seen a couple of videos of these engines running and I don't see steam only water. I now some people take out the thermostat and that could be why. Just in case people ask, I did run it inside a barrel with water
I'm a noob to boats and outboards but not to engines. I've worked on cars all my life, big first gen Nova fan currently own a 62 nova wagon three row seater. thanks for the help and any other info for the noob would be appreciated.
With Thermostat
No Thermostat
My question is, I wasn't getting the tell tale water coming out, but you could see air (not steam) coming out of the hole. I took the water pump apart a couple times thinking I missed something but both times everything was good. After searching for ideas in the forums I took out the thermostat and ran the motor without it. Now I get good water coming out the hole right away. Put the stat back in and no water so I kept running it keeping an eye on the engine temp with a digital temp gun and once it gets warm after a couple of minutes I see some steam and water coming out at about 115 degrees engine temp. Engine running great.
Is this steam normal? I've seen a couple of videos of these engines running and I don't see steam only water. I now some people take out the thermostat and that could be why. Just in case people ask, I did run it inside a barrel with water
I'm a noob to boats and outboards but not to engines. I've worked on cars all my life, big first gen Nova fan currently own a 62 nova wagon three row seater. thanks for the help and any other info for the noob would be appreciated.With Thermostat
No Thermostat
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