[QB93Z]

In my experience, the radiator fins become clogged with very fine sand. I had a radiator that was showing signs of insufficient cooling due to reduced air flow. I removed all the shrouds and the fans and fan assembly. Then I blew compressed air though the fins from the back using a stiff tubing with a right angle tip.

Then I removed the radiator and held it up to the sun and there were two circles (where the fans are) that let through less light than the edges.

I placed the radiator front down on the cement, lifted it about 6 inches and slammed it down on the concrete. On the cement, there were two circles of grit. I did this several times, then blew air through (backwards) and repeated.

I eventually got most of the fins cleared somewhat and reinstalled the radiator. I ended up replacing the radiator a few months later because I still felt that the air flow was reduced.

One good thing about removing the radiator was that I could straighten out all the fins that I bent using the pressurizer air wand.

Jim