I saw this post and was hoping some one would have a cool trick on how to clean the core without having to remove it.

I recently had to replace the radiator due to a leak, so figured that while I was going I may as well give the system a flush to start with the new radiator and a clean system. Well the flush seamed to work well. I started to get leaks around the thermostat housing. Took the hoses off and found very corroded housing. Replaced the housing and everything seamed OK.

Then about a week later, on one cold morning, no heat. Took the same route of pulling off the hoses at the firewall, and used the garden hose to back flush. Put it back together and all seamed good for a couple of weeks and then no heat again.

Ah well, warmer weather at the moment, so on the back burner for now, but guess I will have to pull it out before winter comes around again. <img src="/forums/images/graemlins/smile.gif" alt="" />