This 10mm battery terminal ratchet makes my eternal screwing up less painful

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Why is this 10 mm and not simply 1cm?

Metric bolts and wrenches are x mm? I was just using a 19mm and a 21mm – not 1.9cm and 2.1 cm.


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Why are you using 10mm side terminal batteries?

I thought the OEM batteries were top terminal, easily and painlessly accessible with either a 13mm or 1/2" wrench.

Maybe I’m remembering wrong. I never actually owned a vanagon myself.

I’m using side-terminal batteries for the auxiliary and the main is tucked under the metal lid and a bitch to reach.

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A house battery that fits in the drivers pedestal is too small to be useful for most of us. I yanked my dead one (44 aH? Wow…) and replaced it with a 160 aH marine battery that lives under the rear bench. Lots of room there. Remove the rear heater and you can stuff a couple of deep cycle batteries in there and go way off the grid…


If this doesn’t do it for me, I am thinking of putting a big deep cycle or two inside the former refridgerator space – but the 44aH served me well, and I’m replacing it with a same sized 50aH.

I make the extra effort to find top-terminal batteries for my electric tractor (it uses six 90lb 220ah lead acid behemoths) but even that doesn’t solve the new-batteries-old-vehicle woes… modern GC220 batteries are very slightly taller than they were in the 70s, so the rear battery compartment had to be made taller, or they’d have shorted out on the underside of the driver’s seat.

It’s so they can print 9, 10, 11 on the wrench and not 9mm, 10mm, 11mm, etc. It’s like a clothing size, supposed to be simpler with fewer characters.

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What is it with Volkswagen and putting the battery under a seat? The old Bugs did that too. I seem to remember they caught on fire occasionally too, when the seat springs contacted both top terminals. Maybe that’s why the newer ones have side terminals.

The battery box on my pre-A 356 Speedster was a joke. Leather straps don’t hold up to battery acid off gassing very well.

Plastic terminal covers are a thing…mine has them.

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decimal points, or, if you’re French, decimal commas, are hard to make out.

There may be a slow movement away from the centimeter, I have a number of camera lenses marked as “20cm”, or “13.5cm.” Now, that seems almost quaint. More modern than the contemporaneous practice of using inches, but still…

Millimeters are the standard units in engineering and construction. I have 9, 10 and 11mm ring spanners. I never call them 0.9, 1 and 1.1 cm. 90 by 45 pine is never called 9 by 4.5 cm.

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I saw one go off like that in Panama City, in 1975. My dad seemed to almost expect it when an extra large person squeezed himself into the back seat. For a well regarded car it had some nasty failure modes.

The Reliant Scimitar had leather straps for the petrol tank. It’s exciting when they fail, I tell you what. Wrenches like this are an absolute godsend, can attest, having had to deal with a Renault 5 clutch cable, which is in a stupid place even by French standards.

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I remember that. Considering my 64 Bug had 6 volt electrics that were too weak to power lights plus wipers or radio and indicators I thought they’d be fairly harmless, but when they shorted under the rear seat they were anything but.

Good times.

Although I guess it’s better than having the gas tank under the passenger seat like old Landrovers (series 1) and 1970’s FJ40 landcruisers

Oe of my favorite cars is the convertible Corvair.

Put things where people expect them…

[quote=“nixiebunny, post:10, topic:103734, full:true”]
What is it with Volkswagen and putting the battery under a seat? The old Bugs did that too.[/quote]

Also MGs. Two six volters in series in my sister’s MGB, one under each rear seat.

There’s actually good reason for it. You want to carry as much mass as possible as low in the vehicle as possible, to make it handle better. Lead acid batteries, of course, are the most concentrated mass in the system, and in a lightweight vehicle they count for a lot. And in the case of the MGs, they were actually balancing the weight as well as lowering it.

Yep, putting the batteries low and between the axles is good, forgetting that steel springs sag with age is bad. We used to put masonite on top to prevent that problem, those fiber-stuffed seats were quite flammable.

Side terminals were introduced to cars as a cost control measure because of the expense of lead. Top terminals use a whole lot more lead. Side terminals are a later design, and better engineered for maximizing anaerobic contact between the conductive bits of the battery lead and the battery, but you often won’t want to use them in a machine built for top terminals, because older machines don’t usually have non-conductive battery boxes.

You need hydrocaps!