i have a 92 accord lx with f22 prelude swap and just cracked the radiator today i know its from overpressure in the radiator itself and ive tried all the problem solving methods every other thread mentions but still having problems going to get new radiator from junk yard did know what else i should check for thermostat is brand new it seems to get no back flow when getting hot doesent go into resivoir so theres no pressure at all coming back from engine but still works somehow its fine when driving but no fans work at all. im going to check volts on them and se the resistance but not sure if itll help any either way just need some feed back on it if at all possable... ive owned the car for 3 years and this is the first problem ive had with overheating.. i also have a high idle but im not careing to much about that right now more important is cooling my engine... but yeah true im getting new rad but if i still have the same problem i dont want to crack the new rad. also ive noticed that it looks like theres 2 thermostats on the block one in front and one behind by the distributor any worry? cause there's a female plug looking like another thermo but i have no male plug to plug into it.... is there only one or two thermostats? ive looked everywhere possable and nothing stats if there is one or two.. id apriciate the help..

 

The radiator cap sets the pressure, not the thermostat. If the system is full and nothing is going back into the overflow tank, check the cap. A faulty thermostat may allow the engine to run hotter - the hotter it is, the higher the pressure.

 

Yup, the radiator cap is just as important. There's two seals on that cap, so you gotta make sure they're good.

 

yeah it seems it does compress the spring on the cap to alouw over flow so would that be the main thing to cause excess pressure to cause a crack? would that also cause the no flow and movement of coolant? i thought it might be my water pump but im still going to check all my resistances and see what else is falty.. so there is only one thermo not 2?

 

Is it actually overheating or just overpressuring?

Should only be one thermostat. The cap is designed to relieve pressure at about 16 psi and allow air and excess coolant to flow into the overflow tank. When you shut off the engine and allow it to cool, any remaining air and the coolant (to some degree) contract and actually reduce the pressure such that it will pull fluid back in from the overflow tank. The intent is to keep the system almost completely full of coolant. If the cap is defective and won't vent, then the pressure keeps climbing until something else gives (like the radiator).

A shop should have a radiator cap pressure tester, or just replace it a try it, or find a way to pressurize the system (through the bleed fitting on the thermo housing), take the overflow hose off, and see what pressure is needed to open the cap (although you risk breaking something else if the cap doesn't vent).

 

yeah my temp gauge goes up so its not flowing threw the engine to cool down. and i got new rad an cap last night putting it on today and pressure test sounds good so ill get that checked...it only overheats when sitting to long when in motion its fine i thought itd be my fans cause when you shut the car off you dont hear any fan spinning after temp has gone more than half way up to cool the engine.