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engine temp

852 Views 13 Replies 4 Participants Last post by  85scarab1
What would be the operating temp for a 1985 mercruiser 260? i started mine up for the first time this year and noticed that the temp got up to 195, and stayed there. Should it be this high? I shut it off and have not had much time to deal with it. but i need to get it fixed by this weekend. Thanks.
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I'm pretty sure that motor has a 135* t-stat. Most stock carb motors run around 140.
well it usually runs about 140. i noticed it leaking around t stat housing. so i took it off to replace the gasket. notice was no t stat in it at all. i put on in it. now it runs at 195. Should i just take it back out, or just get a 135° t stat?
I run the Merc 142* stat and it never gets over 150 even after a long wot run. What size thermo did you put in it? If you put an auto one in its going to be around 195.
yep thats it 160° one from autozone for $2.99. so i guess just go get one of the 142° ones from the marina. i will pick one up tonight and put it in. so what is a good range to be in? 140-160? what is considered "OVER HEATING" thanks for the information.
Well even with a 160 it should be 170ish max. Since there was no thermo in the housing. Do you have the parts to put a thermo in? I hope you didnt pull the housing, say hey, no thermo and put one in the manifold. It not located in the manifold like a car. Inside the housing theres a brass sleeve and rubber O ring that need to be placed in there along with the thermostat.
Is there a how to on this? any pics illustrations etc. Thanks.
5# is thermo 6# o ring and 7# is sleeve. 9# and 4# is gaskets.
ok i get what your saying, i just need to get one of the t-stat kits that has everything in it. I will get one today. Thanks a lot for that info and the diagram. helps me out a lot.
It will have everything but the sleeve. you need the sleeve. Its about 7 bucks

When you take it all apart I like to use a small wire wheel on a drill and get into the housing and clean it up really good. flaky rust can hurt the seal of everything and if any rust breaks loose it could jam up the thermo keeping it closed or open all the time.
thanks again. I will try to get that stuff, and get it done today so I can run it this weekend.
Your temps should be running around 150-160 , If there running higher than that After the correct merc. T-stat is in, I would suggest you check the impeller in the drive..
Thanks, i should know more tonight when i get a chance to put the new t stat in. You guys are a big help on here. i cant thank you enough.
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