antifreeze

[sail410]

Any tips or tricks to use when changing antifreeze in a 6lp yanmar? Is there a procedure somewhere?
Thanks in advance, Bill

[Cape Codder]

I've done this every season as recommended.
It's just about 3 gallons of red/pink/orange extended life anti-freeze. I use pre-mix 50/50 Havoline of Prestone extended life (5-year) anti-freeze. (Wal Mart $10-11/gal)
First, I remove the storage boxes from the hatches on either side of the engine box to get clear access.

If you look at a schematic of the 6LP, you will see a drain valve on either side of the block.
I attach 2-3 ft of clear plastic tube to the drain. (3/8" tubing I think). I tape the tube to a 9-10"piece of coat hanger so I can push the tube onto the drain, because you CANNOT reach your hand in that far to the engine block. Once the tubing is secure to the drain, I place the tubing into a small bucket or empty gallon jug. I don't want that stuff draining into the bilge, as it is messy to clean up. The drain is released using a metric 10 or 11 mm socket, and a 6"or longer extention.

Open the radiator cap on top of the engine to allow air into the block, then open the drain on one side of the block until it is fully drained into your container(s). Repeat on the other side of the block.
Close the drains when done, and pour fresh pre-mixed anti-freeze back into inlet/radiator cap on the top of the engine. Fill completely, and re-cap.
I also pour some into the over-flow tank on the side of the engine and fill to the "cold" mark.