Need help with my overheating Mazda

I have a '92 B2200 that I've rebuilt the engine (I bought it not running). I had the head rebuilt and pressure tested. The thing overheats. Not extremely but all my Mazda trucks I've had stay about 1/3 up the gauge. This one goes to about 2/3 and if I turn on the heater full blast, It will go down to a little over 1/3. The upper and lower rad. hoses are "plump" and I can hardly squeeze them with my fingers. I have a new rad. cap and a new thermostat. Any ideas?

my daily does the same thing

is it any better on the highway? or worse?

Can you hear the fan roaring when you rev the engine?

The radiators have a tendency to get plugged up. So do the cats. If it gets hotter on the highway like when climbing a hill, I'd suspect the cats. If it is better on the highway, I would suspect the fan. If it doesnt seem to matter, I would suspect the radiator.

I switched out the fan this morning...didn't change anything. I got an old rad. cap, pulled the rubber seal off, got it up to temp, and put the small rubber tube that goes to the overflow into a glass of water to look for bubbles. There were none so I don't think the exhaust is preasurizing it. The cat near the manifold is hollow and exhaust comming out the tailpipe seems normal. I have another radiator to try. I'll let you know what I find out. Could a bad thermostat cause this?

I tried the new radiator....yes, It works like a champ. Thanks RUSS-D.

hey great to hear!

Where did you get the new radiator and how much was it?

I just robbed it from my project truck. It wont need a radiator fore a while. I'll just have the clogged one boiled out. It's still in good shape.Originally posted by SpokaneMazda



Where did you get the new radiator and how much was it?

glad to hear you got that truck to stop overheating Kevin.

I put a chrome grill on my truck and man it runs at like -30 degrees now! The chrome allows the air to slip past and right into the radiator fins so much faster than the painted grille, it's amazing. I bet I shaved a second off my quarter mile times! I'm going to put chrome all over my nutsack!