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Collection, Preservation and Display of Old Lawn Mowers

rotary blade removal

Hello to you all.

My first rotary mower is on the bench, got it running but poorly due to intermittent spark, advised that it is probably due to a magnet issue in the ignition, as this mower is purely for display I am not overly concerned regarding the running but more the visual appeal so decided to strip it down for paint prep.

As the rotar blade won't go through the little shaft hole in the chassis, this was my first port of call so the engine can be unbolted and lifted off.

Undid center bolt and with it came the washer and a collet or cap, happy days, the blades are actually attached either end of a carrier plate that spins on the shaft and is held in place by a keyway type slot in the shaft. I can only see the top of the slot above carrier plate.

It's stuck fast, tried every lubrication product in the garage, tried to lever off with anything I could find, ( note to self, don't use a piece of softwood with a knot in it as it almost broke your nose).

I checked for pins and grub screws before I must add so it must be just stuck tight. Any ideas, I don't own a blow torch so I cannot heat it and with the amount of WD, brake cleaner, spray grease and paraffin on it I would probably be on the news if I put a flame to it, and I don't own a puller of any description, 

So apart from going shopping for new tools, can anyone suggest another way. Ta.





wristpin Tue, 05/02/2019

Now you have the blade off do you actually need to get the boss off? Unless you need to change the lower crankshaft oil seal the boss can usually be left in place for engine removal.

If the boss has to come off, and in a commercial situation, it would be a case of heat - and plenty of it. We would remove the fuel tank and drain the oil and then protect the sump with a couple of pieces of steel sheet with U slots placed overlapping from either side and then covered in wringing  wet rags. Then apply heat from the oxy acetylene. A recent development is the availability of "motor trade sized"  induction heaters designed for just this sort of job without the use of naked flames and  the associated fire risk, insurance and gas bottle  costs. 

Without a suitable heat source you could try begging and borrowing a hydraulic puller  but there's not a lot to get hold of. To give it a fighting chance try shocking it to break the rust seal between the boss and the crank.  To do this you will need two substantial hammers, one a bit heavier than the other . Hold the heavier hammer (or suitable lump of iron) against one side of the boss and then strike the opposite side as hard as you can. working your way around the boss,turning it to give the best access. Then get a tin that is tall enough to accommodate the boss and crank and wide enough to support the engine placed on top. Fill the tin with heating oil or diesel  and stand the engine on top making sure that the top of the boss is immersed . Leave it for a few days and hopefully the oil will have crept into the interface between the crank and the boss and will aid its removal.

Good luck.    

hortimech Tue, 05/02/2019

Everything Wristpin said, plus, it might help if you told us what the machine actually is, photo's always help.

Lee Smallwood Tue, 05/02/2019

Thank you both and sorry for a crappy description, the mower is a Suffolk galaxy. I'll attach a photo at the end.

Wristpin, the boss you described is part of the spinny plate that holds the two "shark tooth" shaped blades bolted to either end, the groove in the shaft that I can see must be a slot for a pertrusion of metal inside the boss to stop the boss spinning on the shaft if bolt becomes loose when in operation, am I correct in thinking this, I didn't think of hitting both sides at the same time, like releasing a tapered suspension joint so I will certainly be giving it a go, I've been trying to hit it off the shaft but worried I'll be doing damage further up the shaft, I'm sure it's shifted a little but I don't really fancy breaking anything at this stage, 

Petrol tank and carb is now off as, if I cannot remove engine I can at least clean  paint it in situ, makes the job a little harder but the exhaust isn't in great condition and I would like to take a closer look at it.

Here's the pics hopefully. Thanks again, ignore the axe, I was trying everything. 


wristpin Tue, 05/02/2019

In your favour, the boss is quite short . Im guessing that its a parallel shaft and not a taper. The horizontal bit precludes the standing in a tin bit so all you can do is to keep squirting your chosen releasing agent around the joint . If you are really keen you could cut a strip of tin, wrap it around the boss with a worm drive clip so that it protrudes above the top of the boss to form a reservoir, and than fill it with "whatever" in the hope that it soaks down.

On the subject of releasing agents, WD is not high on my list. Diesel or Kerosene is cheapish and effective when left to soak and Plus Gas probably the best proprietary product . If you trawl the net , particularly US sites you will find a variety of home brewed potions , many involving a mix of Automatic Transmission Fluid and Acetone. Coca Cola that contains a percentage of food grade Phosphoric Acid has its fans!!  (other Colas available etc!!!)…

Lee Smallwood Wed, 06/02/2019

Thanks, cannot open link on my phone, so will try when I'm on my tablet,

Let you know how it goes.

Are you getting fed up of looking at that pony yet?

Chris G Sat, 09/02/2019

Even if its for display, worth getting it running and cutting right - no?

Not sure if its a "looker" :-)

Lee Smallwood Sat, 09/02/2019

Beauty is in the eye of the beholder, for instance I find my misses attractive, as for getting it running right, it's the second ignition unit I've fitted and still isnt behaving, so except for sourcing another unit to try I'm out of ideas. Thanks for the picture, only colour picture of the corporation I've seen with the cream handle and engine, see my older post "corporation conundrum"

wristpin Sat, 09/02/2019

Re the advertisement for the Corporation , I’m wondering what the “ unique safety cut out device “ could be?

Lee Smallwood Sun, 17/02/2019

WP. After starting and increasing revs the clutch engaged itself and stalled engine, haven't played with it to see why but it may have something to do with the safety feature, or it's not working properly.

Pete56 Fri, 26/07/2019

Lee that really is a good job. That is inspirational to us new starters in the reconditioning of lawn mowers. I have just started to recon a Suffolk Punch 14S which I'm scrambling around for some information for engine and carburettor etc.

well done!

Pete S.

Lee Smallwood Fri, 26/07/2019

The first mower which started this obsession was a 60s colt. I'm a huge fan of Suffolk's, although not clued  up on the technical specifications of engines, model numbers etc, I have 8 differents Suffolk's in my collection now, some restored, others left as found,. I'm not in the slightest mechanically minded so struggle with engines. I am currently "messing" about with a Pony I've finally acquired after searching for one for a year or so, it has been my holy grail of suffolks.

Your in safe hands with Wristpin, he knows his stuff.  Thanks for the comments on the galaxy,welcome to the club and enjoy your new hobby, it'll get under your skin.


My colt


And after

Pete56 Fri, 26/07/2019

Thanks Lee

How long did it take start to finish?

Will you be able to get the relevant transfers?

I don't mind the project growing on me. I will look forward to it... The frustration at present is getting information. I have no idea who made the engine etc... Oh well take care Lee


Pete S.

Lee Smallwood Sat, 27/07/2019

Hi Pete, the colt took a while as it needed a new ignition system, and a mechanic mate to get engine running, I've just been to the garage my collection is stored in, the colt has been in there for around 10 months, first pull it started with the old fuel in it, and ran like a dream, 

The website is full of information in makes and models so hopefully you'll find what you need, and with photos Wristpin will probably know. 

Various transfers are available on here, if not available here online is your best bet. The colt ones came from Australia..