Alan L.
Elite Member
I don't know how the title got changed to "C Yukon CL coolant leak". Should be 2001 GMC Yukon XL coolant leak"...anyway.....
I posted other threads about doing various maintenance on this 195K mile vehicle and our trips, most recently to Red River, NM, which is where we are right now. I debated changing out the water pump before the trip but consensus was not to, both on this and other boards since it was not leaking or making noise. Our trip from north Texas and then from there to here were uneventful until this morning when we were about to head to town.
The "low coolant light" came on and stayed on. I checked under the hood and in the coolant reservoir the level appeared to be maybe a half inch from the full mark. Went ahead and drove to town to the one repair facility, really under the assumption that the water pump was leaking. I talked to the mechanic who was busy and he said bring it back in 3 hours, and that he had the part. I arranged to bring it back for him to look at, but meanwhile i crawled under it and sure enough I could see a couple of orange colored watery drips trying to form on the bottom of the A/C compressor which is mounted on the lower right side of the engine. Say one drop actually let go.
After killing and restarting the engine, the low coolant light has not come back on.
Drove back to the cabin about 4 miles and crawled under there and dried it off with a towel, then let the truck idle for 15 minutes and checked it and could not detect any more leakage. With a flashlight I looked all over and around the water pump and could not detect any leakage anywhere. What appeared to be the drain hole on the pump is perfectly dry. Based on this I cancelled my appointment with the repair facility (was going to take a long time in which we would be without a vehicle and overly expensive IF he actually did change out the water pump).
After another trip to town and back I spent some more time looking around under there and the drips were back on the bottom of the a/c compressor, and I finally got in position where I could train the flash light to the bottom side of the thermostat hosing which is brand new from when they replaced the thermostat a couple weeks ago. It appears to be wet on the very bottom of the housing to the seam where it attaches to the other housing where the 2 heater hoses attach, whereas the part where the heater hoses attach is perfectly dry.
Bottom line it appears to me the new thermostat housing is leaking, very slow. So I made the decision not to do the emergency repair here but to figure I can make it the 600 miles home, keeping an eye on the coolant level. I can't see anything around the water pump and all and the shaft is not wobbling at all. I topped off the coolant level (up to the full mark in the reserve tank) and plan to head home early in the morning. Hope we make it.......
I posted other threads about doing various maintenance on this 195K mile vehicle and our trips, most recently to Red River, NM, which is where we are right now. I debated changing out the water pump before the trip but consensus was not to, both on this and other boards since it was not leaking or making noise. Our trip from north Texas and then from there to here were uneventful until this morning when we were about to head to town.
The "low coolant light" came on and stayed on. I checked under the hood and in the coolant reservoir the level appeared to be maybe a half inch from the full mark. Went ahead and drove to town to the one repair facility, really under the assumption that the water pump was leaking. I talked to the mechanic who was busy and he said bring it back in 3 hours, and that he had the part. I arranged to bring it back for him to look at, but meanwhile i crawled under it and sure enough I could see a couple of orange colored watery drips trying to form on the bottom of the A/C compressor which is mounted on the lower right side of the engine. Say one drop actually let go.
After killing and restarting the engine, the low coolant light has not come back on.
Drove back to the cabin about 4 miles and crawled under there and dried it off with a towel, then let the truck idle for 15 minutes and checked it and could not detect any more leakage. With a flashlight I looked all over and around the water pump and could not detect any leakage anywhere. What appeared to be the drain hole on the pump is perfectly dry. Based on this I cancelled my appointment with the repair facility (was going to take a long time in which we would be without a vehicle and overly expensive IF he actually did change out the water pump).
After another trip to town and back I spent some more time looking around under there and the drips were back on the bottom of the a/c compressor, and I finally got in position where I could train the flash light to the bottom side of the thermostat hosing which is brand new from when they replaced the thermostat a couple weeks ago. It appears to be wet on the very bottom of the housing to the seam where it attaches to the other housing where the 2 heater hoses attach, whereas the part where the heater hoses attach is perfectly dry.
Bottom line it appears to me the new thermostat housing is leaking, very slow. So I made the decision not to do the emergency repair here but to figure I can make it the 600 miles home, keeping an eye on the coolant level. I can't see anything around the water pump and all and the shaft is not wobbling at all. I topped off the coolant level (up to the full mark in the reserve tank) and plan to head home early in the morning. Hope we make it.......
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