I'm over heating all the time

[MCKINZIE]

I have a 1985 Sun Rey 17' OMC stren drive it has a 4 cyl 2.5 liter I think might be 2.0. I took it out on the lake three months ago and it ran great never has over heated.... I tool it to another lake and it over heated I took it out and removed the thermostate and ran it out of the water with the hose and earphone things and it ran hot put the thermostate back in and remove the water pump to see if the shaft was broken was not and reinstalled it and took the small hose off the back if the stren drive that runs to the thermostate housing and ran water thru it that way and it ran cooler..... I have the water hose on full and not very much water comes out when the engine is running. The motor has always ran about 160-170 and now it climbs fast to over 220 ? Not getting any water in the oil, I never use any oil at all ? so kind of lost dont know anything about stern drives..... <br />any one have a idea ?<br />

 

[merc 140 pontoon]

Re: I'm over heating all the time

I have lots of ideas, but no solutions yet to my overheating problem. See this link and this link. Good luck.<br /><br />Steve

 

[Boatist]

Re: I'm over heating all the time

I not sure which motor you have as right on the cross over form the OMC Stringer to the OMC Cobra.<br />Either way I suspect you have a plug exhaust manifold so water can get in but can not get out so water just heats up.<br /><br />On the stringer engine Outdrive water pump pumps water up the the thermostat houseing. The engine circulation pump suck that water into the engine and circulates it in the engine. <br /><br />When the thermostat reaches about 160 degrees it opens and allow hot water to flow into the exhaust manifold and out thru the riser and down and out the prop. This water is replaced by cold water and engine runs about 160 degrees.<br /><br />Things that can cause it to run hot.<br />1: Outdrive water pump not pumping water to the thermostat houseing.<br />2: Engine Circulation pump bad so does not circulate water in engine.<br />3: Thermostat bad and fails to open at 150 degrees.<br />4: Exhaust manifold or riser plugged up with rust and scale so hot water can not exit engine. Very common in saltwater engines.

 

[luisito]

Re: I'm over heating all the time

i have 2.5 mercruiser 4 cil 153 cid 120hp<br />have the same problem i change the impeller and the problem stay the same then i sent the manifold to be cook at hight temp. on a shop and was plug the water don't circulate.<br /><br />disconect the hose between termastat & intake then<br />conect a garden hose and put water thru, water comes out at the exaust with no problem if no water or little water comes out check manifold for blockage

 

[mah81164]

Re: I'm over heating all the time

I also had the same problem. I went ahead and rebuilt my outdrive. I was taking a lot of air in from a air leak. I replaced all my seals,0-rings and gaskets. I also siliconed the tar out of my water intake neck. I have a volvo penta outdrive.<br />here is a link that helped me:<br /><br /> Click here for help <br /><br />Good luck