My 92 si has been running a little hot lately... i thought it was a leak in one of the main radiator hoses so i replaced them and it still runs hot. How can i tell if my thermostat is bad or my water pump isn't working properly? thanks.

 

Did you check to see if your radiator cap is bad?. You can tell my first looking at your coolant resivoir. Is it empty when the engine is hot?? If so, check the radiator cap. Take it off and see if the rubber ring gasket is swollen past the metal piece it sits on. Also check to see if it's cracked or missing. If so, then you've got a bad radiator cap. Which in the long run, gives you a bad radiator. Because you see, when pressure builds up in the radiator, it pushes up against the plate with the spring behind it. The springs pushes back and lets the air vent out through the hose to the coolant resivoir. With a bad cap, no pressure is let out.. Good luck and be careful. I'm not responsible for any mishaps that might occur. Do this at your own risk.

 

hmm, good idea although i don't think it's the cap. I'll check it out though, i don't have any more ideas. I thought it could be my thermostat but if that was the case, there would be no fluctuations like there are now. I'll inspect the cap. Thanks.

 

Head gasket blown
Clogh is cooling system
Bad mixture -- air bubbles

I would recommend flushing and filling (properly) w/ honda type 2 coolent. Drain block, radiator, and use bleed screw.

 

it may be my head gasket, but i didn't notice any oil in the coolant when i drained it and there's no smoke coming out my exhaust.

What's the "proper" way of flushing the system?

What would be the most likely thing to break and cause a clog (i think that's what you meant) in my coolant system?