The new car battery can't possibly be the right physical size. Got it clamped down and it wasn't, quite. So much for fancy online find-the-right-battery software! Connected the terminals and started the car anyway, then spent far too long improvising with some leftover oak trim to ensure the battery would stay put,* a loose lead-acid battery being something you never, ever want under the hood. Electrical capacity is right and it's too darned cold to be fussy. I'll do something better in the Spring.
Clamping nuts on the terminals take a 10 mm wrench, the size 3/8" won't fit and 7/16" ruins, so I used a combination (box end/open end) 10 mm wrench like I was some kind of savage. I have a set of standard and deep-well 1/4"-drive metric sockets on my Amazon wishlist now, waiting for the next time I am flush with an extra $32 American. --Not that Craftsman sockets are made here any more.
* Growing up in a small town and keeping cheap cars running on a budget, I am no stranger to improvising mounts for a wrong-sized battery -- because that's all the auto-parts place had at a price I could afford.
BUILDING A 1:1 BALUN
1 month ago