so my jeep an 87, started overheating today, and when i got home i saw it was leaking a good amount of fluid, so i popped the hood open and noticed it was coming from the coolant reservoir, the cap was broken. at first i was thinking it was the tstat, im gonna replace the tstat anyways, but i was just wondering if the broken coolant reservoir cap could cause it to over heat..thanks

 

if your losing fluid there that sounds like the issue...especially since you haved the older closed cooling system

 

ok, ok i had a feeling it was that, and good to know its a closed system lol
ill change both of those tomorrow and see if that helps.
thanks

 

After you replace the tstat, make sure to burp the system. That alone was causing mine to overheat.

 

this is even more important with this system due to the hot air being trapped in it

 

ok, ive read some ways of burping the system,
correct me if im wrong, but it sounds that the easiest way is to leave the reservoir cap off, pouring coolant half way to full line running the system to operating temp, shutting it off and adding fluid as needed then just put the cap back on.

 

while cold, fill till you cant anymore, then when it heats up the thermostat will open and you can fill more keep going till you cant anymore(while at operating temperature) then cap off quickly and your done.

guess it dosent have to be COLD but not hot.

 

i may sound like an idiot for this, but from what you said im assuming the reservoir has to be completely full at all times??

 

pretty much^

 

about 1/2 to 3/4. allow some room for expansion.

 

dam, im surprised mine hasnt overheated before, well see you guys later, gotta go run outside and fill mine up lol
well thanks for your guys help, fixed my problem, and taught me some really important stuff..lol