Hi everyone. I am going to explain my full situation so it is apparent why I am asking this question. I have suffered from poor compression for a while and chalked it up to bad apex seals. The other week I got the add coolant buzzer on in my car, but I never overheated so I assumed the sensor was bad. Upon checking my coolant I realized: 1) I was running the orange **** from the previous owner instead of green. 2) the coolant was pressurized to the point that I was unable to fully remove the rad cap without coolant spraying, even on a cold engine. I think that my coolant seals are going bad and that is causing the poor compression which is allowing combustion gasses to escape into the coolant system, that is also why my overflow tank appears to be so far over the full line. I need to flush the coolant system to prevent any further damage. I think I understand how to do that, my main question is how to flush the overflow tank? Do I need to take it out? Will it drain ok by itself to where it won’t be a problem? If I need to take it out, how?

 

the overflow tank is 2 bolts and it lifts out

 

yeah I made this post and then went home and looked at it and now I feel really stupid lol

 

if you do think a coolant seal is bad and causing over pressurization, ive foudn a few cars wehre if i pulled the over flow cap off, i coudl smell the gas/exhuast in the overflow tank(while cars off)

 

one of the test for piston cars is to put the emissions tester in the radiator cap, if combustion is getting in there it will read

 

When you flush your coolant system, do yourself a favor and get a coolant bleeder kit ( ). It's basically just a big funnel with a coolant cap adapter so that you can properly bleed the system without spilling. This will also give you an indication whether the coolant seals are blown or not. While you're bleeding the cooling system (keep the car running with the funnel attached), you'll see a steady stream of small bubbles emerging through the coolant if the seals are blown (also known as the "champagne test").