OutdoorKing Repair Forum Forums General Discussion Forum OutdoorKing Showcase My 1954 14inch Acto Mower

pics of my 1954 14inch Acto Mower in original condition, only replaced the fuel line. Last pic of ID tag. What does the letters mean?

There was one of these in a scrap pile near here, when i went back it was already scrapped

steveford ,

That is one good looking machine. I have two of them myself and they really run smooth.

It looks as if one side of the fuel tank has been mounted to the wrong hole. The tank is supposed to be level.

Hi Grumpy
No, it�s just an optical illusion due to the angle of the photo.
This old girl runs well but she gets a vibration on hard surfaces when the revs go up. I suppose the engines weren't balanced real well back in 1954!

I had a very old 12" ATCO for a few years, and it had fairly extreme vibration, especially at idle or on hard surfaces. I do not think it is a question of engine balance: single cylinder engines inherently have fairly awful balance. All you can do on cheap engines is minimize the mass of the piston and rod (hence aluminium pistons), and "half balance" them by adding a counterweight of half of the reciprocating mass to the crankshaft. When the capacity gets larger that alone is insufficient and you have to add specific measures such as counter-rotating shafts or reciprocating balance weights. B&S do that on their bigger engines, but not on push-mower engines.

Does your engine have an 18 mm spark plug thread, like mine did? That is the test for being really ancient. I just kept cleaning the original plug - new ones were way too expensive (spark plugs have had 14 mm threads since before WW2).

Hi steveford, great to see the ATCO in original condition, and running so sweetly. Yes, they do vibrate a little on hard surfaces, but that is just the nature of the beast. Just remember to go over the machine with a spanner occasionally, so as you don't lose anything in your lawn that might go through your reel (with disastrous results)
on a good score.

Hi Grumpy

The spark plug is about 18mm, you need a shifting spanner to undo it. I suppose the poms would have been using witworth spanners to fit it!

Steve, I used a 10" shifting spanner on mine, because I didn't have a fixed spanner to fit. It may have been Whitworth, I didn't try to find out. Your muffler is quite different from mine, but otherwise the engine looks similar. I have an idea they didn't make any 12" ATCOs after WW2, so mine may have been even older than yours, I didn't ever read the brass plate to find out.