Yanmar Coolant Expansion Tank Replacement
Posted: Fri Mar 11, 2022 5:04 pm
I got in a hurry today and broke some stuff and spent a lot of money - so here's how not to do it:
My port engine coolant expansion tank had a slow drip, which I've done a great job of ignoring. The boatyard work is wrapping up and we're getting ready for sea trial Monday morning ... and, damn if the leak did not worsen considerably overnight.
Conveniently, the tank still had it's original sticker with the Yanmar part number on it ... except the part number on the sticker is for the sticker itself, not the tank ($4.17 each at Mastry Engine Center, should you need the sticker.)
Fortunately, Mastry had the tank in stock (what a relief !) ... at $106.73 plus tax (Part Number 720445-44200). I briefly considered modifying a small milk jug to use as the tank...On the upside, the new tank is very clean and shiny, and comes with a new shiny bracket and lid, and even includes the new sticker. (There must be a reasonably priced equivalent tank out there somewhere.) (The photo is the original tank.)
Back at the boat, I was very excited to remove the old rusty bracket. The mounting screws were stuck, so I pushed hard on the screwdriver, whereupon a loud "snap" let me know that there is no support behind the little board that the bracket attaches to ..., so be sure and grab the bottom of the little board before you exert any pressure on the screws.
My port engine coolant expansion tank had a slow drip, which I've done a great job of ignoring. The boatyard work is wrapping up and we're getting ready for sea trial Monday morning ... and, damn if the leak did not worsen considerably overnight.
Conveniently, the tank still had it's original sticker with the Yanmar part number on it ... except the part number on the sticker is for the sticker itself, not the tank ($4.17 each at Mastry Engine Center, should you need the sticker.)
Fortunately, Mastry had the tank in stock (what a relief !) ... at $106.73 plus tax (Part Number 720445-44200). I briefly considered modifying a small milk jug to use as the tank...On the upside, the new tank is very clean and shiny, and comes with a new shiny bracket and lid, and even includes the new sticker. (There must be a reasonably priced equivalent tank out there somewhere.) (The photo is the original tank.)
Back at the boat, I was very excited to remove the old rusty bracket. The mounting screws were stuck, so I pushed hard on the screwdriver, whereupon a loud "snap" let me know that there is no support behind the little board that the bracket attaches to ..., so be sure and grab the bottom of the little board before you exert any pressure on the screws.
