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Collection, Preservation and Display of Old Lawn Mowers

Fuel additives?

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I have recently acquired a Villiers Mk25 engine which I have put on my Atco 28" Groundsman. Engine and mower is all in good nick and I plan to use it this summer to cut some grass tennis courts. 

My question is what fuel should I be using and should I put an additive in with it?

Look forward to some advice.

Forums

wristpin Mon, 18/02/2019

There are two reasons for considering the use of an additive .  The first is to combat the possibility of valve seat erosion from the use of lead free fuels. The second is to reduce the detrimental effects of the addition of ethanol to pump fuel.

Taking the first, valve seat erosion ; it  very unlikely to  affect a big old low stressed lump like a Mk 25, particularly if only mowing “ a few tennis courts” .  Manoeuvring a 28” Groundsman within the confines of a tennis court may well be a greater source of operator stress.  If you are concerned a drop of lead substitute or even good old Redex, will not do any harm.

The ethanol issue is not quite so clear cut ; not the least being that the present level of around 7% is scheduled to be increased to 9 and maybe 13% at some point in the future. Wether  or not the B word will change this, remains to be seen.

A lot has been written about the possible detrimental effects of ethanol on various fuel system alloys and components - such as fibre glass fuel tanks on some motor cycles  - that won’t affect your Atco. I will stand correct but I have not seen any of the above mentioned issues to date. What is fact is that ethanol blended fuels do have a reduced shelf life before they “ go stale” , loose volatility and eventually degrade to an evil gum in the fuel system. 

The current advice is that fuel should only be bought in a quantity that will be used within a month. While this may be a bit over cautious, this seems to work and is a no cost option compared with bottles of patent medicine.

 

Henno Tue, 19/02/2019

I have started using Aspen last summer; the mower starts better / easier, runs smoother, has almost no smell when running, carb stays clean. Iam only using 95RON in the car.

And yes, it is expensive. The good things mentioned above outweigh the cost.

 

djg745 Wed, 20/02/2019

As a professional gardener I have been using Fuel Fit by Briggs and Stratton for some time  I use it in 2 stroke machines that get used infrequently, especially my chainsaw. Before I began using the additive the chainsaw was very difficult to start after a prolonged non-use period. Now it will start first time, run smoother and not cut out for no apparent reason.

I now use Fuel Fit in all my vintage machines as a matter of course and have no problems with starting them after several months or so of inactivity. A Suffolk Punch I recently bought, which hadn't been used for two years, fired up after very few pulls. Possibly the carb. had been run dry by the previous owner and there was no build up of stale fuel in the tank, but very unlikely looking at the condition of the mower. When some Classic 2 stroke oil arrives this week I will use some Fuel Fit in the mower as a first resort, the mower having compression and a good spark.

Yes there is a cost with any additive, but at 20p a litre when bought off ebay, I am very pleased with the results. Some may cry 'snake oil' but it works for me, and 20p is little to pay compared with time spent getting a reluctant chainsaw to work!

I don't work for B and S, there are other additives out there!

 

 

gtc Thu, 21/02/2019

Looking at the MSDS for Fuel Fit, it contains quite a cocktail of ingredients. About the only thing missing is gunpowder:

  • Hydrocarbons, C10-C13, n-alkanes, isoalkanes, cyclics, aromatics (2-25%)
  • Solvent naphtha (petroleum), heavy aromatic
  • 1,2,4-trimethylbenzene
  • Solvent naphtha (petroleum), light arom.
  • phenol,2,6-ditert., butyl-
  • Mesitylene
  • Naphthalene
  • 2,4,6-Tri-T-Butyl phenol
  • 2,6-Di-tert-butyl-p-cresol
  • Polyolefin alkyl phenol alkyl amine
  • 2-Tert-Butylphenol
  • alpha,alpha'- propylenedinitrilodi-ocresol
  • Xylene
  • 2-Ethylhexan-1-ol
  • Benzene, 1,2,4-trimethyl-
  • Cumene
  • Propylbenzene