Originally Posted by Les_Ismore
Hey, I owned this truck! And did exactly this when my truck had exactly this problem. Are you speaking from direct experience?
1) Pull off the upper radiator surround (8 bolts with 10 mm heads) plenty of room now smart guy.
2) Sure, but if you dont have coil cleaner, use what you already have.
3) An unskilled pressure washer user can destroy a radiator, a garden hose never will. Soak, wait, flush for 5 minutes- its a 30 minute job including dis/assembly.
It took me a lot longer than that to flush my radiator on my current car out, I sprayed it with my hose and it took 30+ mins before all the bubbles were gone. I wanted to clean my condenser, but the rad was right behind it and it took forever. I was using foaming coil cleaner though. That's why I suggested the pressure washer, you need the pressure to get through both the rad and condenser, else you sit there wasting water and time. It might have been the coil cleaner, because I did my intercooler which has larger passages and it still took forever to rinse.
If you can spray from the inside I would deffo recommend the coil cleaner. If your condenser is in front of the rad and you spray the cleaner from the inside, the foaming action will hopefully penetrate to the front of the radiator. Honestly I would do both sides, you might as well clean both the condenser and radiator while you are there, then you can be 100% sure you do not have a blockage and get increased ac performance as well.
EDIT: Parents' have an 04 Sierra 5.3 Z71. 03 was the facelift year but I'm sure it's the same inside the engine bay.
Hey, I owned this truck! And did exactly this when my truck had exactly this problem. Are you speaking from direct experience?
1) Pull off the upper radiator surround (8 bolts with 10 mm heads) plenty of room now smart guy.
2) Sure, but if you dont have coil cleaner, use what you already have.
3) An unskilled pressure washer user can destroy a radiator, a garden hose never will. Soak, wait, flush for 5 minutes- its a 30 minute job including dis/assembly.
It took me a lot longer than that to flush my radiator on my current car out, I sprayed it with my hose and it took 30+ mins before all the bubbles were gone. I wanted to clean my condenser, but the rad was right behind it and it took forever. I was using foaming coil cleaner though. That's why I suggested the pressure washer, you need the pressure to get through both the rad and condenser, else you sit there wasting water and time. It might have been the coil cleaner, because I did my intercooler which has larger passages and it still took forever to rinse.
If you can spray from the inside I would deffo recommend the coil cleaner. If your condenser is in front of the rad and you spray the cleaner from the inside, the foaming action will hopefully penetrate to the front of the radiator. Honestly I would do both sides, you might as well clean both the condenser and radiator while you are there, then you can be 100% sure you do not have a blockage and get increased ac performance as well.
EDIT: Parents' have an 04 Sierra 5.3 Z71. 03 was the facelift year but I'm sure it's the same inside the engine bay.
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