damit, still have pressure
damit, still have pressure
I bleed my cooling system, n wen i drove it... it was fine, no pressure. then the next day i drove it again, n it came back. can anybody help me. thanks.
Re: (DAEDALUS)
but if i drive it 4 a long time, the hose might burst. and one time i drove it, then i park, i squeez the hose n it is hard. so i left it alone till the next day when i open the radiator cap, coolant splash all over my face. m like thinking, why the heck is it like that. isnt theres something i can do? can u help me? i just bought my 240 4 a grand, m thinking of just selling it, but i really wanna fix it kos i love 240s. thnks
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Bronze MFP
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Re: (Bronze MFP)
so you mean to say the radiator hose getting hard is normal? u think its just my radiator cap? thanks
The cap is a supposed to release pressure at a certain level, usually around 10-15psi. It releases coolant into the overflow bottle to limit the pressure when things are hot, and the it allows coolant to be sucked back in when the coolant cools down. There should not be any pressure in the system when it's cool...just not possible theoretically with good coolant. It expands when hot and contracts when cold, so I'm confused too. Replace the cap with a factory one for now. Don't use aftermarket unless you know exactly what the cap's rating is supposed to be (from shop manual).
Re: (98s14inaz)
ok, i will buy a new cap. thanks 4 helping me guys. I'll get back at u
Re: (98s14inaz)
i change the cap already, but its the same. i drove my 240 for a few minuites, then i parked it the i went off island for 3 days, then when i came back, i open my cap n alot of air came out, the pressure been stuck in there.
Re: (DAEDALUS)
It doesn't matter where the pressure is coming from, the cap should bleed it off after the car is stopped.DAEDALUS wrote:I don't think the thermostat would cause that. Maybe it's a blown head gasket or a cracked block? Pressure from the cylinders is pressurizing the system?
http://www.thetoolwarehouse.ne....html
I would first do a pressure check on the cooling system, just in case it is a block or head gasket. If they checks out and it's not leaking, it's an obstruction in the cooling system, possibly a stuck thermostat, or a radiator cap, with the radiator cap being the most likely.
Re: (MikelZ)
good thinking, i cant belive i didnt think of that lol
if you take the cap to any shop, they should have a pressure tester, it should open from 10-14 psi according to the FSM IIRC
if you take the cap to any shop, they should have a pressure tester, it should open from 10-14 psi according to the FSM IIRC
The thermostat is a single point in the circuit; even if it was sealed shut the system should equalize pressure throughout after the car is shut down. This suggests that there is still 10-14 psi pressure after it cools down. I assume the cap is OK since it was just replaced. Regardless, why should there be any pressure in there after the coolant cools down? It should contract to it's original density and actually create a vacuum to suck back whatever was released past the cap. Even if the cap was sealed shut and the thermostat was sealed shut, 3 days after running the car the system pressure should be exactly as it was the last time it was opened up (atmospheric), assuming ambient temperatures are the same.
Re: (drag)
A lot of air came out? There should only be coolant. You can try pressure testing the system as suggested. A tiny hairline crack in the block may not show up, but a larger one will (i.e., it doesn't leak at 14 psi, but it might at 600 psi). How does the oil look? Not milky at all? Is there not a lot of white smoke in the exhaust?drag wrote:i change the cap already, but its the same. i drove my 240 for a few minuites, then i parked it the i went off island for 3 days, then when i came back, i open my cap n alot of air came out, the pressure been stuck in there.
Re: (DAEDALUS)
my oil is ok, i just changed it. n no there is no white smoke. n i dont think that theres a place here to pressure test. this dam island sux. but if they do, how much you think it willl cost?
Re: (DAEDALUS)
hey guys, thanks for all your help. my problem is done. I just keep trying diffrent caps n keep on test running, i found the right one, n now pressure is releasing to the coolant resevior. u guys been a big help. thanks you all. maybe later i have more questions. PEACE OUT! Neo...........