Ask the Mechanic

Color Matters

(Getty Images; Photo Illustration by Barry Falkner)

READER: I'm overhauling my John Deere 1020 tractor. The sealing rings that go in the bottom of the block are different colors. Does it matter which sealing ring goes on the top and bottom?

STEVE: Yes, it does matter. It really matters. One color is designated for sealing the top of the liner to the engine block, holding in coolant. It's made to be resistant to coolant. The bottom ring is made to be resistant to oil and seals engine oil in the crankcase. It also serves as a backup to seal coolant from getting in the oil pan. The sealing rings usually have a color-code designation in the package. If you did not get directions with the sealing rings, do not chance it.


-- Write Steve Thompson at Ask The Mechanic, 2204 Lakeshore Dr., Suite 415, Birmingham, AL 35209, or email, and be sure to include your phone number.


Past Issues