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Collection, Preservation and Display of Old Lawn Mowers

Grandads Mower

Hi All,

I am looking for some advice.

I have got my hands on my Grandads old Suffolk Colt Petrol mower (Model Number 75G 14 24A). I have fond memories of my Grandad showing me how to fill the tank, how to start the mower, and the sound of it still rings true. However this was over 25 years ago and my Grandad has since passed away. I have recently moved house with big Garden and wanted a better mower than our existing electric flymo type mower. Low and behold going through my grandparents old garage I found the suffolk colt. I now have it in my possession as my Nan has since got a newer lighter model for her gardener.

So, I have this beauty in my garage and i haven't got a clue how to use it :)

But i do want to see if it works first!? Can anyone tell me what petrol i need to use. Also is it a 2 stroke model or 4 stroke?

I understand 2 stroke you mix the oil and petrol (at a certain ratio) if 4 stroke do you do the same thing?!

Any advice is welcome, as I want to get this beauty cutting my grass :)

Best wishes


wristpin Wed, 13/05/2015

It's a 4-stroke and runs on ordinary pump fuel, no mixing required. It was made in the days when there was "leaded" petrol and one of the functions of the lead was "preserve"  the valve faces and seats in hard worked engines. In your application the lack of lead is not really anything to worry about but if it bothers you you can add a drop of a lead substitute from somewhere like Halfords..

No oil in the fuel but it does have a oil sump and after such a long period of inactivity it would be a good idea to drain any oil and fill with fresh oil up to the mark on the dipstick. Mower shops, garden centres etc usually sell "Lawnmower Oil" in half litre bottles.

If it was put away with fuel in the tank and carburettor there will probably be a smelly gungy mess in both which will take some serious cleaning.

Hopefully, If it has been dry stored the valves wont be stuck but it would be a good idea to remove the spark plug and put a spoonful of clean oil into the cylinder and turn the engine over a vew times  before refitting the plug.

Assuming that it's old enough to be pre-electronic ignition,after such a long period of storage you will be lucky indeed if there is still a spark as some corrosion will probably have formed on the face of the contact breaker points  and will need to be cleaned off.

Could go on and on  - all depends on how handy you are with things mechanical !

If you post an image of the machine I'll see if I have a suitable Owner's Manual and will scan it and post it on this forum for you.

mattycustard Wed, 13/05/2015

Wow, thats brilliant, Thanks wristpin for all the above information. Much obliged!

I will get you a picture of the complete lawnmower.


steveb Wed, 13/05/2015

Stick with it Matt, they are beautiful machines - almost works of art.

I will probably be a fight to get it going but once it runs it should run and run. I use one that is significantly older than me, yet it seems to be in significantly better condition than it's owner...

If however you are not mechanically minded (and these machines are basically very simple, needing to be being internally clean and adequately lubricated) then you may need to find an old school lawnmower agent to give it the once over - or find a neighbour of the right vintage :)

beware of moving parts as it probably pre-dates most modern safety mechanisms. Change the oil once per year, use "lawnmower oil" and not car oil - and once you free it from it's likely rust induced torpor it should do you proud. 




--edit-- if it is the 75g14-24a, a manual is here 



wristpin Wed, 13/05/2015

The reason that I asked for an image was to make a positive Identification of the " Suffolk Colt". The manual posted by SteveB is for a "Super Colt" - essentially a different machine.

Which do we have?

hortimech Wed, 13/05/2015

Don't really need a picture (providing  it is a Suffolk and a 12" cut)

Does it have a clutch lever on the handles and are the side casings made out of alloy, or is there a round knob on the left hand side that takes the rear roller out of gear and the side casings are made out of cast iron ?

First is a super colt, second is a colt.