Another Closed To Open Cooling System Conversion Success Story
Another closed system bites the dust. I'm sure these systems work much better in cooler climates, but this summer in the Southern California dry heat was the last straw. I really wanted to make the closed system work so I could stay factory but now I'm really glad I gave up. Theres nothing worse than sitting in traffic on a hot day (or the drive thru), or towing something up a hill or wheelin in the hot desert and not being able to use the A/C because the truck will overheat. I went through three different closed system bottles; the first one cracked, the second new one began leaking at the cap so it wouldn't hold pressure and the third "aluminum" one workd but didnt solve the overheating issues entirely. The closed system has to be burped after every overheat too. The thermostat can be modified to allow easier self-burping but still didnt solve the problem. Filling the system up was a pain unless you pulled a radiator hose to do it. When I replaced my stock tires with a set of 31x10.5 BFG A/T the overheating issue was exagerated in those key areas. What a Pain in the Butt!
So I finally bought a 92 cherokee 3 row radiator with a lever-vent cap. Filling it up at the lever-vent cap took 1 minute. Now my temps are locked between 195-200 deg no matter what I throw at the truck. Towing heavy loads, a truck full of people, up hill, in the desert with the AC on, running the big tires on stock gears... 200 degrees stable, 1/16 below straight up and down on the guage, all day long. I wish I hadn't have been so hesitant to do this a long long time ago.
Whle I was in there, I replaced my heater control valve next to the stock bottle as I had read it makes the A/C blow colder due to it fully blocking off the heater core. Yep, that worked too - very cold now, not just cool. The entire swap took about an hour with my basic limited tools I keep under the back seat. I also bought a new thermostat housing which has the a sensor mount in it from a 92. The 92 radiator does not have a sensor mount like my 88 had on the drivers side. While the part number showed the same part, mine didnt look the same so I skipped that. I read it was supposed to send a signal to is the dash temp guage as well as trigger the electric fan. Part of the conversin was to involve splicing longer wires here (polarity doesnt matter). Well my model doesnt have any electric fan and my guage is still working normally so I'm still looking for what this might control. I plan on purchasing the correct sender for the new thermostat housing I bought so I can wire up a dual electric fan setup and eliminate my clutch fan setup.
Part Numbers:
1992 3 core radiator (ask around, my place in SoCal said they are extremely popular and even provided me with the closed to open converions information)
I didn't end up using the below parts, but instead bough a generic at pep boys due the the mounting hardware and better fit.
Coolant Bottle: Mopar #52027984 (in stock but tall and ugly)
Coolant Bottle Cap: Mopar #4682828 (not stocked)
Heater Valve: Mopar #56005900
7 feet of 1/4" fuel line from radiator to overflow bottle (pep boys, kragen, etc)
If you are in a pinch, you can mostly reuse all the hoses and hose clamps that are on there but its a good time to replace all that including the 5-6 feet of 5/8" hose. Dont forget to flush the system and add 2 quarts of coolant.
Also, I cut open the ends of my old radiator and inspected the stock 2 - core. I rodded each tube looking for obstructions. It really wasnt in that bad of shape, which supprised me.
Thats it, Thanks
for keeping this information available to the masses. It definately made a difference in my ride!
- Mike
Another closed system bites the dust. I'm sure these systems work much better in cooler climates, but this summer in the Southern California dry heat was the last straw. I really wanted to make the closed system work so I could stay factory but now I'm really glad I gave up. Theres nothing worse than sitting in traffic on a hot day (or the drive thru), or towing something up a hill or wheelin in the hot desert and not being able to use the A/C because the truck will overheat. I went through three different closed system bottles; the first one cracked, the second new one began leaking at the cap so it wouldn't hold pressure and the third "aluminum" one workd but didnt solve the overheating issues entirely. The closed system has to be burped after every overheat too. The thermostat can be modified to allow easier self-burping but still didnt solve the problem. Filling the system up was a pain unless you pulled a radiator hose to do it. When I replaced my stock tires with a set of 31x10.5 BFG A/T the overheating issue was exagerated in those key areas. What a Pain in the Butt!
So I finally bought a 92 cherokee 3 row radiator with a lever-vent cap. Filling it up at the lever-vent cap took 1 minute. Now my temps are locked between 195-200 deg no matter what I throw at the truck. Towing heavy loads, a truck full of people, up hill, in the desert with the AC on, running the big tires on stock gears... 200 degrees stable, 1/16 below straight up and down on the guage, all day long. I wish I hadn't have been so hesitant to do this a long long time ago.
Whle I was in there, I replaced my heater control valve next to the stock bottle as I had read it makes the A/C blow colder due to it fully blocking off the heater core. Yep, that worked too - very cold now, not just cool. The entire swap took about an hour with my basic limited tools I keep under the back seat. I also bought a new thermostat housing which has the a sensor mount in it from a 92. The 92 radiator does not have a sensor mount like my 88 had on the drivers side. While the part number showed the same part, mine didnt look the same so I skipped that. I read it was supposed to send a signal to is the dash temp guage as well as trigger the electric fan. Part of the conversin was to involve splicing longer wires here (polarity doesnt matter). Well my model doesnt have any electric fan and my guage is still working normally so I'm still looking for what this might control. I plan on purchasing the correct sender for the new thermostat housing I bought so I can wire up a dual electric fan setup and eliminate my clutch fan setup.
Part Numbers:
1992 3 core radiator (ask around, my place in SoCal said they are extremely popular and even provided me with the closed to open converions information)
I didn't end up using the below parts, but instead bough a generic at pep boys due the the mounting hardware and better fit.
Coolant Bottle: Mopar #52027984 (in stock but tall and ugly)
Coolant Bottle Cap: Mopar #4682828 (not stocked)
Heater Valve: Mopar #56005900
7 feet of 1/4" fuel line from radiator to overflow bottle (pep boys, kragen, etc)
If you are in a pinch, you can mostly reuse all the hoses and hose clamps that are on there but its a good time to replace all that including the 5-6 feet of 5/8" hose. Dont forget to flush the system and add 2 quarts of coolant.
Also, I cut open the ends of my old radiator and inspected the stock 2 - core. I rodded each tube looking for obstructions. It really wasnt in that bad of shape, which supprised me.
Thats it, Thanks
for keeping this information available to the masses. It definately made a difference in my ride!- Mike