It's that time of year and past time for a comprehensive discussion on the topic!
If your truck is overheating, please, figure it out and fix it, or you'll be forcing me to write a dissertation on replacing head gaskets!
First step when overheating, allow the truck to cool and ensure that you have a full cooling system. The second step is if your fears are due to the gauge on the instrument panel, beg, borrow or steal a non-contact thermometer and confirm the truck is really overheating. Temps should not exceed 220'F. Of course, if you have coolant boiling out of the cap, we do have presumptive proof the truck is getting too hot.
Next, check the viscous clutch on the fan. When the truck is cool, it should have slight resistance to turning. When the truck is warm or hot, there should be significant resistance to turning. The least expensive replacement is one for a'98 GM 4.3l Vortec engine. You will have to slightly enlarge the mounting bolt holes, but it's a small price to pay for the savings.
Secondly, Thermostat. Far less likely a culprit, but sometimes they do fail. A replacement for a small block Chevrolet works fine if you bore an 1/8" hole in the mounting flange for a vent.
Lastly, the radiator. I list it last, in spite of it most likely being the culprit. These radiators are cross flow and build up crud at a high rate. Replacement radiators are expensive, as a result, the first step should probably be to pull it out and haul it to a radiator shop for flow testing and chemical cleaning. If this doesn't do the trick, you may be able to have the radiator rodded where the tanks are removed and cleaning rods passed down the cooling channels. If the core is beyond repair, it may be less expensive to have a new core installed. Worst case, replacement is indicated. Will Tillery should be able to help you out.
Once you get the radiator working, most likely your hoses need to be replaced-do it! Also, regardless of the quality of water and coolant, it is critical to dump and refill your cooling system at least every two years.
The aux fans should =be tested to ensure they turn freely, and work when power is applied. The easiest way to apply power is to turn the A/C on and the fans should come on. If not, find out why.
Good luck!
PT
If your truck is overheating, please, figure it out and fix it, or you'll be forcing me to write a dissertation on replacing head gaskets!
First step when overheating, allow the truck to cool and ensure that you have a full cooling system. The second step is if your fears are due to the gauge on the instrument panel, beg, borrow or steal a non-contact thermometer and confirm the truck is really overheating. Temps should not exceed 220'F. Of course, if you have coolant boiling out of the cap, we do have presumptive proof the truck is getting too hot.
Next, check the viscous clutch on the fan. When the truck is cool, it should have slight resistance to turning. When the truck is warm or hot, there should be significant resistance to turning. The least expensive replacement is one for a'98 GM 4.3l Vortec engine. You will have to slightly enlarge the mounting bolt holes, but it's a small price to pay for the savings.
Secondly, Thermostat. Far less likely a culprit, but sometimes they do fail. A replacement for a small block Chevrolet works fine if you bore an 1/8" hole in the mounting flange for a vent.
Lastly, the radiator. I list it last, in spite of it most likely being the culprit. These radiators are cross flow and build up crud at a high rate. Replacement radiators are expensive, as a result, the first step should probably be to pull it out and haul it to a radiator shop for flow testing and chemical cleaning. If this doesn't do the trick, you may be able to have the radiator rodded where the tanks are removed and cleaning rods passed down the cooling channels. If the core is beyond repair, it may be less expensive to have a new core installed. Worst case, replacement is indicated. Will Tillery should be able to help you out.
Once you get the radiator working, most likely your hoses need to be replaced-do it! Also, regardless of the quality of water and coolant, it is critical to dump and refill your cooling system at least every two years.
The aux fans should =be tested to ensure they turn freely, and work when power is applied. The easiest way to apply power is to turn the A/C on and the fans should come on. If not, find out why.
Good luck!
PT
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