I have a 94 Mazda b2300 it was working great last week then all the sudden it started making a knocking sound and started to overheat! Its still drivable but it overheats if i go far! A friend told me it can be the Water Pump so i put a new one, I was told it can be the Thermostat so i had a new one put in. It worked for awhile but began overheating again. My truck is my livelihood so its important i get it fixed! I cant afford a mechanic but just asking to see if anyone knows what it could possibly be? It catches good and the engine sounds strong but it keeps overheating!
Your friends and Kirk don't seem to be working for you. The knocking sound has me concerned and I'm not sure how it plays into the overheating. First the antifreeze level? After the water pump and thermostat you should have bled the air out of the system. Don't think you can fill the reservoir tank and it will be okay. Take the cap off the radiator to confirm it is full. Next is the fan. If it is electric you need to make sure it is working if it is belt driven you need to grab the blade and give it a push, it should not spin free and should only go about one blade past where you pushed it. Engine off for that one please. Next the radiator it self. Make sure the fins and not blocked and air can move through them.
Have the radiator wiped clean out. My Mazda truck radiator did a similar ingredient, and that i trust that you've a similar difficulty. in the experience that they could't clean it on the radiator shop, you're able to replace it.
Did you put the thermostat in facing the right direction? Did you flush the cooling system? Check the fan to make sure it is working.
Tell your friend thanks bot no thanks for any more automotive advise. If you had checked your upper radiator hose for HEAT with the engine running 20 minutes you didn't need a thermostat or a water-pump. Lets do things in the order of cost and effectiveness: #1. Ask a trusted private mechanic to do an inexpensive *cooling system pressure test to see if you have any external or internal coolant leaks. #2. Replace the electrical temperature sensor in the water-jacket. #3. Cooling systems need to be drained flushed and *cleaned every five years. When was yours done last? #4. You're five years overdue for a new radiator even with the best of cooling system care. When was the last time that your cooling system has been drained. flushed and cleaned with a one part powered acid cleaner? By now, your five years overdue for a new radiator
