Good evening,
I have a 1987 chevy S10 blazer with the 2.8 that runs around 230-240 deg. I changed the radiator which was real bad. I thought that would do the trick but she still runs up in the 230deg. A few months ago I changed the thermostate could this have gone bad running at such hot temp.? Has anyone heard of such a thing. Also I checked the clutch fan but am not sure how to check it. I know you check the resistance after 2min. of running then drive her and check it again but I really don't feel any noticable diffrence. Is there anyone who has had this problem in the past & is there a way to leave the radiator cap off while running and check the circulation? Thank you!

 

Hey there, had the same problem but on a different vehicle but wouldnt hurt to try, mine ended up being the thermostat, it was only a couple months before it went bad that i bought it, but the wether changing could even do it, go to your local parts store and ask them too look it up in the computer and see what it calls for wether its low medium or a high temp thermostat, during the summer time you would want to try to get a low temp as you dont want the car overheating, things can go bad at any time, and to start off cheap i would just change the thermostat and make sure you have plenty of coolant in the radiator, if that doesnt seem to solve the problem you could try to check the water pump to see if their is any kind of leak and also could be the coolant temerature sensor, did the check engine light come on at all, might be able to get a code if it did and that might tell you your problem. Well good luck and keep posted!

 

I would consider the fan clutch............Seen a ton of em on S10 P.U.'s and Blazers go bad and cause the A/C compressor to blow seals.........
CAREFULLY sneak your hand behind the fan while the engine idles and see if you feel a good flow of air .......also look at the blade and if it seems like you can grab it and stop it.............(gloves please) you probably can

 

Good evening!
Yes the check engine light comes on when the temp. gauge hits around 230 I have jumped the a & b terminals but get an O2 sensor which I have replaced. The only thermostate I can find at my local part store is a 195 deg. I found a few 165 deg. ones on ebay but they will not fit. I have good surge in the top hose when I pinch it. there are no leaks out of the water pump & as far as I can feel there is good air flow from the fan. I have not checked that one sensor but then again I'm not sure where that sensor is or how to check it. I was just thinking I put the thermostate in months before I changed the radiator. Could this of ruined the thermostate. another thing is I could never figure out how much water to put in so it's a 50/50 mix and was woundering if this could be the problem?. I mean this thing jumps up to 245 deg. within a matter of 5 min. & takes forever to cool down. Any other sugestions would be very helpful! Thank you!