ok guys so the cooling system in the 87 -90 xjs suck ass. recently my buddy was telling me that i can do a conversion to change it over to the newer system. just wondering if any of u guys have a good write up or have done this. i need to know what exactly to buy and from what years etc. i dont know anything about cooling systems other than how to change the water pump t stat and fan clutch. im confident i can do it, just need some tech info. thanks.
-
Welcome to the new NAXJA Forum! If your password does not work, please use "Forgot your password?" link on the log-in page. Please feel free to reach out to [email protected] if we can provide any assistance.
cooling system conversion?
- Thread starter bails85
- Start date
- Location
- WA state
I believe there is an FAQ on this. if not here then over at cherokee forum.
Actually, the closed system is amazing when its functioning properly. I have not had any problems with it on any XJ's that I have had. Only issue I ever had was the POS heater valve. And a stripped bottle cap for the reservoir.
Actually, the closed system is amazing when its functioning properly. I have not had any problems with it on any XJ's that I have had. Only issue I ever had was the POS heater valve. And a stripped bottle cap for the reservoir.
xcm
NAXJA Forum User
- Location
- Southern Oregon
5' of 5/8th's heater hose.
91+ radiator, 19(?)lbs radiator cap,
91+ heater valve (optional, i dont run one. definately dont buy one from autozone)
91+ radiator overflow bottle, and hose to connect to the radiator.
i stuck up for the closed system for way too long, get rid of that shit. it's like a dana 35, first time you need a new radiator, convert over, putting any money into a closed system is wasted money.
91+ radiator, 19(?)lbs radiator cap,
91+ heater valve (optional, i dont run one. definately dont buy one from autozone)
91+ radiator overflow bottle, and hose to connect to the radiator.
i stuck up for the closed system for way too long, get rid of that shit. it's like a dana 35, first time you need a new radiator, convert over, putting any money into a closed system is wasted money.
joe_peters
NAXJA Forum User
- Location
- Grants Pass, OryGun
XCM has it right, except it is a 16 lb cap (the parts monkey will want to sell you a 13 lb cap, and you will have a lower boiling point if you use it).
cheapcherokee93
<----boat-manche
- Location
- Guadalahabra, CA
or if you're cheap like me just do something like this:
just add a reservoir tank and your good to go
just add a reservoir tank and your good to go
luvherinmyjeep32
NAXJA Forum User
- Location
- Pennsyltucky
I used a 92 XJ radiator, and because it didn't have fittings for the axillary fan temperature switch, I had to get a 92 XJ thermostat housing from the junkyard with the 92 XJ auxiliary fan temperature switch in it. I used a cheap, universal coolant recovery bottle from the parts store. No need for that tall factory one that would have to mount where our coil is mounted on the fender. Thermostat and housing gasket were the same. Get rid of the heater valve. Those things are a pain in the ass. At Advance Auto you can buy 2 plastic connectors with hose clamps in the Help! stuff section that does the job.
I had the same thoughts about my closed cooling system when I first got my MJ. However, after reading, researching, and tinkering I found the Closed system is way better, my '87 cools better than my '00. Once you get the system burped (with the two hole method in the thermostat) and get a good rad cap, you're set. (I'm running a Volvo cap)
And keep in mind, I run my MJ hard through the blistering desert in Barstow and the like. 105+ degrees and no issues.
And keep in mind, I run my MJ hard through the blistering desert in Barstow and the like. 105+ degrees and no issues.
cruiser54
NAXJA Forum User
- Location
- Prescott, Az
A real help on the closed system is to use the Stant 10244 cap on the expansion bottle. Joe recommends this and it works well. They don't seem to strip, hold a higher pressure, don't rub the hood when the bottle espands, and they're less that $10 at Napa.
tribalmentality
NAXJA Forum User
- Location
- Stonewall, Manitoba, Canada
if youre rad is tsill good, then go to the wrecker and steal an upper rad hose from a 2000-2003 dakota or durango. it has the rad cap built in. make that work as youre upper rad hose and turn youre pressure bottle into a return bottle. or just buy the whole set up for a 91. i got a 94 rad and an aftermarket coolant bottle, any way you go about it, its pretty easy.
- Location
- San Diego
