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Overheating Problems... HELP!

I have a 1990 Chevy 1500, 350 2WD. I cannot get truck to stop overheating. I have replaced the intake manifold gaskets, collant temp sensor and connector (broke it while removing from sensor), thermostat and the radiator cap . I have flow of coolant in the radiator and I even took off the waterpump and the bearings and fins seem to be fine. I am leaning toward the radiator being partially clogged or the fan cluch going out. Which or what do you all recommend trying next?? Also, when I took the fan cluch off in removing the waterpump I noticed some considerable resistance in spinning the cluch, is this normal or reason to replace?? Please help, I cannot afford to continue replacing parts with no luck. Thanks

The clutch and fan only cool the car when it is sitting still at idle. As soon as you start moving, even 15 or 20 mph the air moving by the radiator is what cools the radiator. If you are overheating when driving down the road it is not your fan or clutch. They may be bad, but is not your main problem. Check you local radiator shops to see if they can “clean” out your radiator. Some new radiators are so fragile they can’t be worked on like the radiators of olden days. If they can work on it; remove it, get it cleaned out, and reinstall it. A clogged radiator in a '90 truck is certainly possible.

Thank you UncleTurbo That makes sense I seem to get frustrated sometimes and cannot think of solutions…Thanks again I will post back with the result of your comment

Take a good look at your 19 year-old radiator . . . if it looks crappy on the outside, you can bet it’s ten times worse on the inside. I had exactly the same issues with my '89 Accord a year ago and changed the radiator, problem solved. The Parts Bin has several for your 1500, from $70 to $200. BTW, I then cut the old radiator apart and couldn’t believe the rust inside . . and I flush and change coolant every two years. 19 years is a long time. Just my two cents. Rocketman

Has the coolant been changed regularly?