Mike1114

1989 Jeep Cherokee Laredo, all coolant parts were original when I got it.

So i replaced all cooling components, hoses, t-stat, water pump, radiator, sensors on the rad for whatever, I changed from closed system to open by getting an overflow bottle and rad cap fitting that T'd into the rad hose, and I flused cooling system including heater core.

I bought an ebay 3 row all aluminum rad and ran it for months, after a while it started weeping out of passenger side where fins meet tank. I figured I got a bad rad so I bought an OEM replacement from autozone. About 2-4 months, bam same thing starts happening, coolant is weeping BAD out of passenger side where fins meet endtank.

Why does this keep happening? What can I do to stop it? Seems like I keep battling cooling issues and loosing. I live in Florida so I need to tame this dragon before summer, everday its 100+ here, hell today its 81!!

DFlintstone

I've gotta wonder if your pressure isn't an issue. You're sure your cap is letting what, 16-18 Lbs free to the overflow? Also your radiator is mounting as it should? Nothing "tweaked" or funky there? I've been thinking of trying the same thing as I'm on, like my 4th bottle! (14+ years). Sorry Btw.

ZINGGG

Good thing with autozone is that they got a lifetime warranty right?? And you can go get a new one free of charge. As for why it keeps happening, I couldn't tell you for sure.

On another note, I would also replace the fan clutch if I were you, as that is the last component of the cooling system you have not replaced

hankthetank

x2, check cap, or get lower pressure cap. My 90 is on its second pressure tank, just replaced last month. Pretty good for 22 yrs old...dont see the heat some of you guys see up here though.

Mike1114

Now that several have mentioned it, I realize that the coolant never overflows into the overflow bottle....

The rad cap that I have T'd into the upper rad hose is the highest point in the system like its supposed to be....Right?

What would cause the coolant not to overflow into the resevoir?

hankthetank

cap not opening...too much pressure? weird

kjc

You used the same cap from your closed system? oops.. Are they even designed to release pressure?

DFlintstone

His ""rad cap fitting that T'd into the rad hose"", should have a conventional cap, with a spring in it to allow pressure over 18 Lbs or so to blow threw to the recovery bottle. Later when the system cools and the air contracts, coolant from the bottle is sucked back into the system.

Mike1114

as DFlintstone said, yes I have a conventional rad cap (there was no rad cap originally in closed system), but I've never seen overflow go into the resevoir......

So the consensus is replace the rad cap and see what happens?

DFlintstone

As far as I know that, or somehow having it mounted tweaked is all that might cause that. Or freezing or crashing! It is really just a pressure relief valve. I think they make them down to 10 or 12 Lbs, at least, if you want to start extra safe.

Are you in, like Fargo, running less than 50/50 ?

DangerXJ

oddly enough i have seen the coolant overflow into the tank several times unfortunatly but I have never seen the pressure suck the coolant back into the system from the overflow; i've lead myself to believe that it won't....

[QUOTE=Mike1114;1517803]as DFlintstone said, yes I have a conventional rad cap (there was no rad cap originally in closed system), but I've never seen overflow go into the resevoir......

So the consensus is replace the rad cap and see what happens?[/QUOTE