I have a problem. My cooling system it keeps spewing out of the upper radiator cap on the thermostat housing. I thought it was the thermostat so i pulled it out to see if it was sticking and it didnt seem to be it. So I left it out to see any ways just to double check . Now it is still spewing and my upper radiator hose is expanding like it wants to blow. But the real wierd thing is that the thermostat housing cap is a !6lb and the radiator cap is a 13lb but it is only the 16lb theromostat cap that spews.

 

you only need one pressure cap. the other should be a flat cap with no spring. Put the pressure cap wherever the overflow line comes from.

 

yea i could do that but it would still be spewing right. Cause the pressure cap isnt stoping up the housing. I went by a place today that deals with just rx7's and he said the pressure cap was fine. but the funny thing is he said he didnt even know what was going on.

 

Are you using an aftermarket pressure cap or OEM? Some people have bad experiences with aftermarket brands like Stant.

Do you mean the coolant is gushing out past the cap? Is the coolant system pressurized when you do this? Or just when you run the car with the car off it will gush out? Possibly blown coolant seal.

If your mechanic only deals with rx7s and doesnt know what's wrong I would take it to someone else.

 

it does it with the car running and when i shut it of untill all the pressure is gone. but why is my upper radiator hose expanding and the 13lb cap on the radiator does not relieve the pressure

 

Sounds like a bad rad cap to me. There's no other possible way to make enough pressure to expand a hose noticeably with a functioning rad cap. Replace the cap and if you still have coolant spewing into the overflow run the car with the rad cap off until it reaches norm. operating temp. If you see a steady stream of bubbles in the coolant than you have a bad o-ring and need a rebuild. If this is the case the car usually smokes a little when you start it after sitting for a while. While your at it make sure that there is a steel coil(like a spring) inside the lower rad hose. It's there to keep the rad hose from collapsing due to suction from the water pump.

 

Your internal water seals may have gone. The pressure from the combustion chamber is getting by and pressurising your system.

 

do the coolant seal test located in the FAQ thread.

 

stant = crap.

 

been doing some new test. this is going to sound messed up. but the top of the radiator is hot and were the bottom radiator hose goes in it is a lot cooler and so is the bottom part of the radiator. Help please. im confused.

 

clogged radiator

 

I found another radiator today i am going to put it in tomorrow

 

it ended up not being a stoped up radiator. Cause flushed it out. Finally got to check my timing it was way out of wack. maybe it will get straighting out. it seems to be doing a lot better

 

Do you have a slant mounted or upright mounted radiator,you may need an air separator tank if you do not have one already,even if your cooling seals are fine.

 

Hmmm, after 2+ years he probably doesn't have the car any longer.

 

i have this same problem after driving for awhile my upper rad cap will start to let coolent gush by it and my overflow tank fills up.

but i have not determined but suspect that its a bad coolent seal although i never get any smoke on startup or running

 

what is the milage on the car? chances are that the water seals are gone. like it was mentioned before the compression is getting to your cooling system. time for a rebuilt?