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Collection, Preservation and Display of Old Lawn Mowers

Hello all and what have I bought?

Hello all.  Just joined the club.  I have restricted myself to Briggs and Stratton and Honda self drive mowers until recently.  I fell in love with a Barn Find. However, this is a big step up for me and I have no idea how to work out what I have bought.  I know it's an ATCO and it has a Briggs and Stratton Industrial/Commercial Engine Cast Iron Bore. The engine

It's a ride on.  I would guess from the 70's but I have no idea.  is anyone able to enlighten me as I need to find manuals on this so I can take the motor out to get the starting cord working etc.

The Mower

It's in great condition overall.  Thanks for your help!

gmadgwick Mon, 04/04/2022

after looking some more I think the engine is a 90000 I/C 475/525 Series engine.  I am unable to see the engine ID numbers.  They are not where the manual I found say they should be.  Is anyone able to confirm my thoughts?


wristpin Mon, 04/04/2022

Looks like an Atco 28” Groundsman that has been re-engined. An early one would have had a Villiers Mk25 and a later one a Tecumseh . The engine may be dated from the Model, Type and Code stamped into the blower housing (air cowl or shroud). As far as the original date of manufacture of the base machine , I’ll guess 1950s. Sometimes there’s an ID tag on the right hand side of the chassis held on under one of the frame fixings.

wristpin Mon, 04/04/2022

I’ve not been able to open up what looks like a row of thumbnail pics along the bottom of your main image but I think that you will find the Model, Type and Code numbers will be on the vertical face of the blower housing on the carburettor side. Other than general interest the age of the chassis isn’t critical as the basic design didn’t change that much. Clues will be changes in the handle bar design etc and someone such as Clive with a collection of brochures may be able to answer that question.

gmadgwick Tue, 05/04/2022

Thanks for the replies!  I will take a look.  I think it is a 36" cutting roll (whatever that s called).  I am just working on the engine and have a broken spring, which I think I can reuse as it is onlt the end rusted off, the rest of it seems stable,  So a grinder job I think.  I will take a look at where you suggest, though I think you are probably correct as it is the only place I haven't really been able to look so far.  I will keep the thread updated.  Anyone with any more ideas are very welcome!

Thanks again.

wristpin Wed, 06/04/2022

Briggs  recoil springs are still available either original or pattern. I think that the width of your machine will either be 28 or 34". They did make a 36" but it would be a far older machine.  

gmadgwick Sun, 01/05/2022

I got the engine running!  Quite scary actually, the shaft spins at such a rate!  I am trying now to move it from my shingle drive.  I read a manual that talks about a dog clutch that disconnects the cutting cylinder from the drive.  The manual did not show what this was.  Is anyone able to help me on how you disconnect this drive?

On other matters, how does this mower get steered round corners?  Is it just that the trailing roller guides the front in some way?  I can't see how this enormous machine gets steered.  I am afraid you may all hear of a guy that started his lawnmower, engaged the clutch and it kept going through fences and cars for a mile or so before he found the kill switch.  

Any advice is thankfully received.  Anyone local to Lightwater, Surrey that can come give me some advice and safety tips would also be appreciated.  Thanks all!