The previous owners never ran a thermostat so I finally put one in. I thought I put it in backwards at first and changed the direction and both times I had the same problem. I fill the car back up and turn it on. It takes a good 10-15 minutes to get up to 180 (that's the thermo I'm using). The temperature then rapidly spikes and my coolant comes gushing out of my radiator. I tried putting the cap back on the radiator but it didn't make a difference. Anyone know what's going on with my car?

 

Does thermostat have a bleeder? If not drill small hole in thermostat and place at 12 oclock position. Refill slowly and will bleed air out. Put cap on radiator and run until up to operating range. Allow to cool and top off.

 

That could be it; hot water unable to talk to thermostat because of trapped air.

Wish I had a dollar for every time one says to drill hole in T-Stat.

Not sure why the factory does not always provide an air bleed hole?

Not sure why I've never had to drill that hole.

 

I've already raged a few times doing this thermostat. I don't think there's enough beer in the world for this job. Something so simple is so frustrating thanks to the ****ty position of the damn bypass hose and right screw.

 

Sometimes it is advisable to purchase a new bypass hose for their flexability compared to old stiff hose. Back about 22 years ago I had the pleasure of doing 125 ambulance safety recalls. Replaced a bunch of heater hoses and after that I'm totally immune to hose difficulties. New bypass hose is like $6.

 

Do you think a bypass hose allows T-Stat to bleed trapped air sufficiently?

So no need to drill hole in T-Stat w/ bypass hose is an urban myth??

 

Is this hole drilled in the fat part of the body near the center of the thermostat? I don't see how a hole in the lip of the t-stat will help considering it's covered by the gasket.

 

Put the spring side towards the intake. If your car is overheating, the water should still be hot enough to see if the thermostat is open when you take it out as long as you don't break the seal of the gasket.

Try running it without the cap off for 3 thermostat cycles and fill when needed. Your hoses should be the same temperature. If it overheats with the cap off, pull the thermostat and check it.

 

Bypass hose will not properly bleed air or you would have no problem. Nobody would have a radiator throwing up. Not the part of thermostat that has spring and moves but outer not where gasket will interfere dill small hole. Position hole at 12 oclock position. Slowly fill and most all of trapped air will be gone. Run until up to operating temperature, let cool open radiator and top off. No mess.

 

I thought you let it get up to operating temp without the cap on to burp out the air, then put the cap on?