I took off the leaky upper radiator hose and discovered a white residue where it was clamped on at the motor. It was on there pretty good, I had to chisel it off. Has anyone experienced this? Is this a warning of some sort? Where did it come from? There was quite a bit there.

 

calcium build up from not using distilled water

 

No big deal you just have hard water.

Grew up with that just clean it off to make sure the hose seals good

I have never used distilled water in a engine in the old days in batteries when they needed topping off.

 

Thanx guys!

 

I discovered the same problem when I changed my timing belt & hoses on my 01 Tacoma V6. The interface for the upper hose was so corroded it would not seal. I didn't see any of the same corrosion under the timing cover or on the water pump but presumably if there is lime scale there it's everywhere. For future reference do not use a chisel or screwdriver. Instead, use emory cloth or sandpaper to clean the scale off the water neck.