Mudd
NAXJA Forum User
- Location
- Bethel Acres, Oklahoma
My 88 XJ had been heating up regularly with the arrival of warm weather. After I got my A/C operational it only got worse. I got a lot of excellent advice when I presented the problem in this thread:
http://www.naxja.org/forum/showthread.php?t=85652&highlight=hiway
I decided the radiator was the culprit based on a few observations:
1) During the first drive of each morning the radiator is nice and cool. As the temp gage makes its first climb and the thermostat opens the temp gage shows a sharp drop. Then it climbs again and drops a little less. The cool radiator is now being heated up. Then it doesn't drop anymore. It just steadily rises regardless of driving conditions or speed.
2) When it looks like a trip into the red zone on the gage is inevitable I turn off the a/c and turn on the heater to full blast. This does not have a favorable outcome with passengers when outside temp is already 100 deg f.
It does, however, drop the temp a little.
So it looks like the radiator is just no longer up to the task. This is the original closed cooling system, by the way.
I called a 1-800-radiator place from the yellow pages and they brought me a Modine 3-row to my house within 2 hours for 140 bucks.
I recently moved, I don't have all my stuff yet, I have a gravel driveway to work in, and it's 100 degrees again. So I didn't run any flush through the system and I didn't pull the block drain. I did do some flushing though:
I pulled the old radiator. I pulled the hoses from the heater core. I pulled the thermostat housing and thermostat. I pulled the temp sensor from the back of the head.
I used a pointy sprayer on the end of my garden hose to flush the heater core in both directions until it came out clear. I stuck the nozzle in the temp sensor hole until the lower hose ran clear, then put my hand over the end of the lower hose. This caused the water to go through the block and come out the front of the head, eventually running clear. Also in the front of the block I could see a water passage on each side of the head. I forced water in one hole and it eventually came out the other hole. Once everything was running clear I figured I was pretty well flushed. This left some tap water in the block and heater core but my well water does not leave mineral deposits on the fixtures in the house so I figured what the heck, good enough.
I buttoned everything back up but left out the temp sensor. I think the system capacity is around 3 gallons so I added 1-1/2 gallons of antifreeze to the pressure bottle. Then topped it off with distilled water until it started spewing out the sensor hole. Then I put the cap on the bottle. This stopped the flow from the sensor hole. I installed the sensor and ran the engine and checked for leaks with the cap off the bottle. You can see some air being purged as the return line dumps into the bottle, which is the highest point in the system. Then I pulled the sensor again. I slowly loosened the cap on the bottle and a little trapped air came out of the sensor hole. I closed the cap to stop the fluid flow and installed the sensor. That should leave it pretty well burped.
I went for a long test drive in the hot weather with a/c blowing and the temp gage never crossed over the 210 mark. Success!
I wanted the fastest, easiest, lowest cost repair so I kept the closed system and upgraded to the 3-row.
Hope this helps anyone suffering the dreaded cooling problems...
John.
http://www.naxja.org/forum/showthread.php?t=85652&highlight=hiway
I decided the radiator was the culprit based on a few observations:
1) During the first drive of each morning the radiator is nice and cool. As the temp gage makes its first climb and the thermostat opens the temp gage shows a sharp drop. Then it climbs again and drops a little less. The cool radiator is now being heated up. Then it doesn't drop anymore. It just steadily rises regardless of driving conditions or speed.
2) When it looks like a trip into the red zone on the gage is inevitable I turn off the a/c and turn on the heater to full blast. This does not have a favorable outcome with passengers when outside temp is already 100 deg f.
It does, however, drop the temp a little.
So it looks like the radiator is just no longer up to the task. This is the original closed cooling system, by the way.
I called a 1-800-radiator place from the yellow pages and they brought me a Modine 3-row to my house within 2 hours for 140 bucks.
I recently moved, I don't have all my stuff yet, I have a gravel driveway to work in, and it's 100 degrees again. So I didn't run any flush through the system and I didn't pull the block drain. I did do some flushing though:
I pulled the old radiator. I pulled the hoses from the heater core. I pulled the thermostat housing and thermostat. I pulled the temp sensor from the back of the head.
I used a pointy sprayer on the end of my garden hose to flush the heater core in both directions until it came out clear. I stuck the nozzle in the temp sensor hole until the lower hose ran clear, then put my hand over the end of the lower hose. This caused the water to go through the block and come out the front of the head, eventually running clear. Also in the front of the block I could see a water passage on each side of the head. I forced water in one hole and it eventually came out the other hole. Once everything was running clear I figured I was pretty well flushed. This left some tap water in the block and heater core but my well water does not leave mineral deposits on the fixtures in the house so I figured what the heck, good enough.
I buttoned everything back up but left out the temp sensor. I think the system capacity is around 3 gallons so I added 1-1/2 gallons of antifreeze to the pressure bottle. Then topped it off with distilled water until it started spewing out the sensor hole. Then I put the cap on the bottle. This stopped the flow from the sensor hole. I installed the sensor and ran the engine and checked for leaks with the cap off the bottle. You can see some air being purged as the return line dumps into the bottle, which is the highest point in the system. Then I pulled the sensor again. I slowly loosened the cap on the bottle and a little trapped air came out of the sensor hole. I closed the cap to stop the fluid flow and installed the sensor. That should leave it pretty well burped.
I went for a long test drive in the hot weather with a/c blowing and the temp gage never crossed over the 210 mark. Success!
I wanted the fastest, easiest, lowest cost repair so I kept the closed system and upgraded to the 3-row.
Hope this helps anyone suffering the dreaded cooling problems...
John.
