B7800 gets hot after about a hour.

[Hay Dude]

Hose it from the inside out. Dust ducked in and got trapped from the outside in do you want to push it out.

Yep. Good point. No sense in pushing it further into the radiator. The key to getting it clean is to rinse it for a long period of time. Some guys will rinse them while brown water is still running out. You really have to get in there and rinse the entire surface area of the radiator until it runs completely clean.

 

[nyone]

I would start by useing a flashlight and trying to see light through all corners of the rad. Many times they can be clogged way in the fins and look clean. The corners are the worst for clogging up as they dont get the same fan flow.