I manage to do my heater core flush today, and it worked great. Thanks to the many threads on the topic in this forum. However, for future reference (I expect to have to do this again some day), I do have a question.

Removing the clamp from the water pump end was a piece of cake, and the one on the thermostat end was a little hard to get at, but not all that bad either. However, I had a heck of a time getting the hoses loose, and I scraped the heck out of my hands on the process. Is there a trick I'm missing out on? I ran the engine for about 4 minutes or so, to try to warm up the hoses. The hoses started to warm up and soften. That made it easier to remove the one on the water pump, but I still had a heck of a time with the one on the thermostat. Should I have let it run longer, so that it starts to actually get hot? (obviously, you'd want to have the radiator cap off to avoid it being pressurized)

 

I use a hose hook tool. It it's like an "L" shaped poker that you run inside the end of the hose and move around the thermostat housing (or heater pipe or rad etc..) between the hose and the metal to break the seal, while gently twisting the hose.

I'd take a pic of the tool but I gotta get to a hockey game.

 

I ended up having to cut the hoses off and replace them. There was no way they were going to come off.

 

Yanking the hoses for the first time after a few years on the connections can be a real challenge. I've used a homemade L shaped tool to try to slip between the hose and the fitting but sometimes you just can't get the darn thing in there and I always worry about gouging the fittings as well. The most successful way I've discovered is to grab the hoses (while cold) with locking pliers (or channel locks) near the fitting and twist them CW, CCW, CW, CCW, starting in small degree increments (like 90, one way, then the other) progressing further and further, until the hoses finally let go. I re-position the pliers as necessary to get the turning range I'm after. I've twisted some hoses a complete 360 before she finally let go and I've never ruptured a heater core fitting yet.

If all else fails, take a razor knife and carefully slit the hose from the fitting about 3/4" long and then twist them off. Most hoses are long enough to still reach even with 3/4" missing. If not, heater hose is relatively cheap to replace. I always chuck the original clamps and use new hose clamps too, and I use a silicone grease inside the hose to put the new hoses on the fittings. The next time they pull off with ease.