Temperature question.
Question:
Try Cleaning the radiator, If its equiped with Air Conditioning a lot of crap builds up between the 2 which may cause overheating
– Hide quoted text — Show quoted text -> What Temp Thermostat do you have installed ? > Fan Clutch test is easy, Remove from vehicle, remove fan blades, place in > pot of water, apply heat, Observe temp that shaft starts to bind. Check > against spec in manual. > Hi, > I have this old truck that I want to keep for some time. 89 GMC S15 4.3 > Auto 4X4. About 160,000 miles. > I use it when hunting and do a lot of slow driving on old logging roads. > On > the open road the temp. gauge rarely comes off the peg (about 160 deg. > F.). > However after a few minutes of crawling along at less than 5mph the temp. > climbs to about 190 deg.. F.). Outside temp. doesn’t seem to have much > effect on this. > Never goes over 190. BTW, I have a mechanical temp gauge . > I’ve asked local friends and received responses from don’t worry, to > check > the fan clutch to get an electric fan. > Looking for help. > TIA > — > 89 S15 4X4 4.3 700R4 Short Box
Response:
I have no idea what temp. the thermostat is. I suspect it’s whatever comes from the factory. I have never replaced it. Got truck in 91 with 40k miles. I assume thermostat is original. (no assume jokes please 
). Thanks for the tip in checking the fan clutch. – Hide quoted text — Show quoted text ->snip<< > What Temp Thermostat do you have installed ? > Fan Clutch test is easy, Remove from vehicle, remove fan blades, place in > pot of water, apply heat, Observe temp that shaft starts to bind. Check > against spec in manual.
Response:
Thanks, Radiator is clean. no AC or Trans cooler, just lots of empty space. One of the first things I checked. – Hide quoted text — Show quoted text ->snip<< > Try Cleaning the radiator, If its equiped with Air Conditioning a lot of > crap builds up between the 2 which may cause overheating
Response:
You might want to replace the thermostat. That much of a temperature swing is way too much for a properly functioning thermostat. It’s also not likely to be a 195F thermostat which I believe is the right one for your truck. Dean – Hide quoted text — Show quoted text – >I have no idea what temp. the thermostat is. I suspect it’s whatever comes >from the factory. I have never replaced it. Got truck in 91 with 40k miles. >I assume thermostat is original. (no assume jokes please ). >Thanks for the tip in checking the fan clutch. >>snip<< >What Temp Thermostat do you have installed ? >Fan Clutch test is easy, Remove from vehicle, remove fan blades, place in >pot of water, apply heat, Observe temp that shaft starts to bind. Check >against spec in manual.
Response:
OK, thanks for all the help. BTW, would another way to test the fan clutch, be to run the engine until it warms up, then turn it off and check to see if the fan clutch is grabbing? Thanks — 89 S15 4X4 4.3 700R4 Short Box
You might want to replace the thermostat. That much of a temperature swing is way too much for a properly functioning thermostat. It’s also not likely to be a 195F thermostat which I believe is the right one for your truck. Dean
I have no idea what temp. the thermostat is. I suspect it’s whatever comesfrom the factory. I have never replaced it. Got truck in 91 with 40k miles.I assume thermostat is original. (no assume jokes please ).Thanks for the tip in checking the fan clutch. snip<< What Temp Thermostat do you have installed ?Fan Clutch test is easy, Remove from vehicle, remove fan blades, place inpot of water, apply heat, Observe temp that shaft starts to bind. Checkagainst spec in manual.
Response:
Yes, that would work. But any fluid drive fan clutch loses some of its ability to lock up over time; about 10% per year. So if it’s 5 years old, it’s not much help at all and should be replaced. The GM replacement is about $100. Dean – Hide quoted text — Show quoted text – >OK, thanks for all the help. >BTW, would another way to test the fan clutch, be to run the engine until it >warms up, then turn it off and check to see if the fan clutch is grabbing? >Thanks >– >89 S15 4X4 4.3 700R4 Short Box >You might want to replace the thermostat. That much of a temperature swing >is way too much for a properly functioning thermostat. It’s also not likely >to be a 195F thermostat which I believe is the right one for your truck. >Dean >I have no idea what temp. the thermostat is. I suspect it’s whatever >comesfrom the factory. I have never replaced it. Got truck in 91 with 40k >miles.I assume thermostat is original. (no assume jokes please ).Thanks >for the tip in checking the fan clutch. >snip<< >What Temp Thermostat do you have installed ?Fan Clutch test is easy, Remove >from vehicle, remove fan blades, place inpot of water, apply heat, Observe >temp that shaft starts to bind. Checkagainst spec in manual.
Response:
Hi, I have this old truck that I want to keep for some time. 89 GMC S15 4.3 Auto 4X4. About 160,000 miles. I use it when hunting and do a lot of slow driving on old logging roads. On the open road the temp. gauge rarely comes off the peg (about 160 deg. F.). However after a few minutes of crawling along at less than 5mph the temp. climbs to about 190 deg.. F.). Outside temp. doesn’t seem to have much effect on this. Never goes over 190. BTW, I have a mechanical temp gauge . I’ve asked local friends and received responses from don’t worry, to check the fan clutch to get an electric fan. Looking for help. TIA — 89 S15 4X4 4.3 700R4 Short Box
Response:
If you got 160K out of your fan clutch, you are one lucky guy! Replace it! Dean – Hide quoted text — Show quoted text – >Hi, > I have this old truck that I want to keep for some time. 89 GMC S15 4.3 >Auto 4X4. About 160,000 miles. > I use it when hunting and do a lot of slow driving on old logging roads. On >the open road the temp. gauge rarely comes off the peg (about 160 deg. F.). > However after a few minutes of crawling along at less than 5mph the temp. >climbs to about 190 deg.. F.). Outside temp. doesn’t seem to have much >effect on this. > Never goes over 190. BTW, I have a mechanical temp gauge . > I’ve asked local friends and received responses from don’t worry, to check >the fan clutch to get an electric fan. > Looking for help. > TIA >– >89 S15 4X4 4.3 700R4 Short Box
Response:
What Temp Thermostat do you have installed ? Fan Clutch test is easy, Remove from vehicle, remove fan blades, place in pot of water, apply heat, Observe temp that shaft starts to bind. Check against spec in manual.
– Hide quoted text — Show quoted text -> Hi, > I have this old truck that I want to keep for some time. 89 GMC S15 4.3 > Auto 4X4. About 160,000 miles. > I use it when hunting and do a lot of slow driving on old logging roads. On > the open road the temp. gauge rarely comes off the peg (about 160 deg. F.). > However after a few minutes of crawling along at less than 5mph the temp. > climbs to about 190 deg.. F.). Outside temp. doesn’t seem to have much > effect on this. > Never goes over 190. BTW, I have a mechanical temp gauge . > I’ve asked local friends and received responses from don’t worry, to check > the fan clutch to get an electric fan. > Looking for help. > TIA > — > 89 S15 4X4 4.3 700R4 Short Box
Response:
Try removing the AC radiator if equiped and blow or wash out the radiator, They collect a lot of crap over the years, I cleaned mine and droped the temperature in half. Jim
– Hide quoted text — Show quoted text -> Hi, > I have this old truck that I want to keep for some time. 89 GMC S15 4.3 > Auto 4X4. About 160,000 miles. > I use it when hunting and do a lot of slow driving on old logging roads. On > the open road the temp. gauge rarely comes off the peg (about 160 deg. F.). > However after a few minutes of crawling along at less than 5mph the temp. > climbs to about 190 deg.. F.). Outside temp. doesn’t seem to have much > effect on this. > Never goes over 190. BTW, I have a mechanical temp gauge . > I’ve asked local friends and received responses from don’t worry, to check > the fan clutch to get an electric fan. > Looking for help. > TIA > — > 89 S15 4X4 4.3 700R4 Short Box
