i was running my engine to test my new digital gauge cluster and i noticed a little steam coming from the radiator cap. i looked at the temp gauge and it was not overheating, upper hose was warm. i was thinking i have a bad seal on my cap but the cap was replaced 2 weeks ago, but i pressure tested it and it held 16 lbs of pressure. the thermostat is stuck open (i have yet to replace it still) could this be my problem? i did do the one thing you never do and that is taking off cap while warm. i never got it fully off cause coolant just blew out and i quickly tightened it back down. the coolant was a little foamy

 

u can block test it to see if u have compression leaking in your coolant..also u sure its not steamy because its burning off old coolant? you can also have a small crack on ur radiator filler neck

 

your talking about a compression test to see if i have a blown head gasket right? the radiator looks fairly new and clean but i will put a pressure test on that too and report back thanks

 

dude you are the man, i pressure tested the cooling system and right away i noticed alot of hissing sounds and coolant gushing from these 3 spots. turns out the clamps were loose so i grabbed my 10 mm ratchet and tightened them im probably gonna toss some new ones on since those look old and rusted. can someone tell me what that line going into radiator in first pic is for? the upper hose is on the opposite side of the radiator this is just a smaller diameter 4th line going into radiator that has me confused