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Collection, Preservation and Display of Old Lawn Mowers

Ransomes Ajax Mk5 Project

Evening All

I've been lurking for a while, getting tips whilst trying to source my first mower online. Managed to pick a Ransomes Ajax Mk5 up on eBay for £17 and have begun to strip it down ready for refurb/repainting and will be using it for years to come. So far the handles and nameplate have been cleaned, sanded and semi-primed ready for painting. I will be posting updates as I go and any tips/help is greatly appreciated. I've had a good look through the forums and there's some great refurbs on here, given me lots of ideas so thanks already!

Hope you enjoy,


Harvey Fri, 09/03/2018

Looking forward to seeing another Ajax restoration. I have a MK5 and two Mk4's.  The only differences that I have found are the front roller configuration and the grassbox shape.

The two 'side' rollers in your picture are for use on longer grass so that  it doesn't get flattened in front of the cutting cylinder. For normal mowing there should be two longer rollers between them which can be fitted after removing the split pins and washers. I had some new rollers made by a guy on e-Bay and I got a new bottom blade also from eBay.

The thrower plate can be removed for when mowing without the grassbox fitted so the cuttings are not thrown in a heap in front of the mower.  It looks as though your thrower plate is fitted upside down. The edge with the cut-outs should slide in first.

If you are intending to paint it as original, the name plate and handle clamps should be silver the same as the side plate castings.

Anything that you need to know when dismantling it I am sure you will get answers here.





SilverFox89 Tue, 13/03/2018

Hi Harvey 

Thanks for the response. Yes I'd noticed the thrower plate and had corrected this, old photo, but a good spot! Paint will be fairly original, have purchased a darker green, personal preference, but sticking to the green/silver/red. 

Tried getting the gears off this evening and really struggled. Managed to get the nut off the large gear, but couldn't get the gear off the axle/shaft. Any tips on how to get this off? The front gear nut is on very tight too, will have to get a longer socket/wrench to try and put some more pressure on it. Grinding paste arrived today so can get on to lapping the cylinder and bottom blade in the next few days. 


hillsider Tue, 13/03/2018

The large gear should slide off the roller shaft if you wiggle it with a pair of levers but it may take some patience as they can become rather tight due to the retaining nut squishing the alloy gear hub.

Re the nut on the cylinder gear I suspect you are trying to tighten it, have you tried turning it both directions? 

SilverFox89 Tue, 13/03/2018

Will try prying it off tomorrow. 

RE the cylinder nut, is this left hand thread like the large gear nut? Whilst I've turned it both ways, I've only put pressure on turning clockwise, thinking it's left hand thread. Will try it the other way and see how that goes. 

Thanks for the help! 

hillsider Tue, 13/03/2018

The cylinder drive gear nut is a normal right hand thread and unscrews in the opposite direct to the roller gear nut. I recently dismantled an Ajax for parts and found out the hard way also.

SilverFox89 Wed, 14/03/2018

Feel a bit dense for not trying that, but glad I'm not the only one to make this mistake! Will try again this eve and see how I get on. Thanks for the help


Harvey Fri, 16/03/2018

Removing the rear roller gear.  I had trouble with that too. Get some  tyre levers or similar behind. Get the ends right in as near the hub as possible and just wiggle them so it rocks the gear slightly with a little outward force. Do not lever near to the outer edge of the gear: you will probably bend or break it. The gear has a slot in the back of the hub  and locates onto a 'pin' through the shaft.


SilverFox89 Wed, 04/04/2018

Evening All

Thanks for the help RE getting the large gear off the axle. Glad to report that after several attempts, frustrated fingers and lots of patience I managed to get it off! 

I've spent the last week taking it all apart, degreasing, sanding off the old paint and it's now nearly ready for undercoat and paint. The two side casings are pretty badly scratched, not really sure what I can do with those other than to polish them out as much as I can before painting. Any other suggestions? Really happy with how it's coming along and can't wait to paint it! 

stonethemows Wed, 04/04/2018

I'm no great expert but I would suggest that the alloy side plates are not intended to be painted. I find that careful rubbing with an appropriate steel wool works well. Actually I'm not sure that the scraper/name plate was originally painted either, none of mine are, the same treatment applies.

wristpin Thu, 05/04/2018

As per the last post, neither of my Ajax have ever had paint on the side frames, just pain alloy. 

Also, the Ajax illustrated in Brian Bell's Seventy Years of Garden Machinery has unpainted side frames and nameplate.

Clive1997 Fri, 06/04/2018

Yes I agree the original alloy introduced post war on the Mk 3 onwards was un-painted side panel & scraper.

 I suppose it is personal choice, customise to taste or restore to original, bit like cars the majority of Escorts are customised but Austin sevens restored. There are so many Mk3, 4 & 5's  around some modified ones won't change history.  If however you are dealing with an early pre-war Ajax Mk1 & 2 perhaps restoring to original is preferred.

If you are restoring to original spec note that the wood rolls changed  from a single long one on Mk 1, 4 of similar length (2 x 3.3/8 2x 3.1/8  on Mk2 , 4 on Mk3, 3 of equal length on Mk4 with the Mk5 having 2 big 2 small, this may of course have altered during production & when the particular parts lists were produced. 

I am pleased to see that the two restorations highlighted via links earlier in this thread a Mk3 & Mk5 both appear to have the correct wood roll combinations for the particular model.

On the subject of Ajax's I seem to be inundated with them at the moment & happy to move some on, probably all Mk's available, message me direct if interested.

If anyone comes across an 1870/80's‘Ajax’ Please don’t customise, leave as original & give me a call!!!

SilverFox89 Fri, 06/04/2018

Hi Clive. Couldn't agree more! 

Once complete it's going to be lovingly used by us, not sold or kept indoors as a museum piece so personal preference with a nod to "original spec" is good enough for me. As you say, if this was a MK1/2 then fair enough, but it's not. I bought it with the sole intention of stripping down, learning how it works, refurb and then use it for years to come and must say that I'm loving the process so far! 

That MK1 looks like a right beast! Will be sure to keep my eyes peeled for one. As a guide, how much would a MK1 be worth/bought for if anyone came across one? 

Clive1997 Fri, 06/04/2018

Hi Chris

Sorry may have confused the issue, the Ajax in the ad is an early one from the USA nothing to do with the Ransomes Ajax. The Ransomes Ajax Mk1 was introduced in 1933 similar design to yours but with straight handles and no alloy. 

The American one is a bit tongue in cheek as I doubt if any have survived!

Harvey Sat, 07/04/2018

You will probably need some new front rollers. I had a set of rollers made for both my MK4 and MK5 by a guy on eBay trading as keypad.

They are excellent.  He gives a choice of woods and I had mine made of oak. If you would like the dimensions for the MK5 I will look them up.  Can't find them right now.

I also bought a new bottom blade from a trader by the name of  chain9921.  £22



SilverFox89 Mon, 09/04/2018

Hi Harvey

Dimensions for the front rollers would be much appreciated. I know they are a 2 small, 2 large configuration, but given I only have the 2 small ones (with worn edges at that) taking measurements is near impossible! I'd followed Keypads eBay listing already so will no doubt be placing an order soon. 

No pictures, but to update, the rest of the parts (ones to be painted) have been primed ready for sanding and paint. I've sprayed the handle assembly and nameplate, both are looking great. Spent many hours sanding and stripping the rust off the cylinder, took ages, but well worth the effort.

Whilst dismantling I had intended to leave the rear roller assembly as it was (it was correctly spaced, central, in very good condition with original paint) however I decided to strip this all down too. The axle was very tight on to the rollers and ratchets, took a good hour to free this up with a hammer and blocks. Found it difficult to get the ratchets off the axle, so decided to knock the axle through instead, worked like a charm. All degreased and ready for paint. Pictures to follow. 

Harvey Mon, 09/04/2018

The Ajax MK5 roller sizes are:

2.1/2" diameter

Two rolls at 1.3/4" long

Two rolls at 4.3/4" long

Note that keypad's 12" price is for a total roll length of 12".  The Ajax rolls are a total of 13" so the price is a bit more; I think £27 a set.

I had some discussion with him (Mike) about the roll sizes as all mine were too worn to measure accurately and he suggested a diameter of 6cm based on others he had made for Ajaxes but I subsequently found the correct diameter to be the 2.1/2".  Best to contact him to discuss your requirements before actually placing an order and he will tell you the procedure to order your 'non standard' roller length.

A photo' enclosed of my MK5 and MK 4 rollers made by keypad.


SilverFox89 Mon, 09/04/2018

Cheers for the measurements! Managed to do some more prep this evening, took photos too. Coming along nicely. 

SilverFox89 Sun, 15/04/2018

Took advantage of the warm weather this weekend and managed to finish off the paintwork and have just finished rebuilding the main unit. Just the handles to finish then can be used. 

Lee Smallwood Sun, 15/04/2018

Ive been enjoying the progress and reading the thread, I'd like to jump in and ask some questions regarding the Ajax range, I have a 3 and a 4 and I was wondering what the differences between the 2 marks should be, visually the 3 has straight handles, the 4 crossover much like your mk 5, cannot really see any other (I've not started tinkering yet) apart from the 3 has a funny Shap collector box 'tapers in towards the top' is this original? It has an Ajax decal so I presumed it is the right one, now I'm not sure, also, I know the 1 & 2 are hard to come by, I have had alerts for them for 6 months with nothing, but I'd be interested in a five if you have one, saw in your post you had a few you might like to move on, I'll be at the rally in may. Sorry to interrupt, great job your doing, very impressed. I did my best with the finish of my Suffolk colt, maybe I should.spend a bit more time on prep to get a finish that looks that neat.



Clive1997 Sun, 15/04/2018

Hi Lee

I will email you direct with further information.





SilverFox89 Sun, 22/04/2018

Very pleased to update and say that I'm all done....almost. Just the grass box to do now, but very happy with how it looks! 

Harvey, thanks again for the roller measurements. In the end we made some from scratch by modifying a couple of rolling pins! They were £4 each from Morrisons and solid beech, dimensions as follows: length 9", diameter 2.5", centre hole 15mm. Bought 2, removed the centre rod, cut to length, widened the centres to 16mm and chamfered the edges. Given the length, managed to make 3 small rollers as spares too. Very very happy with how they turned out. 

All adjusted and did a quick test run and works and cuts like a dream. 

Anyway, hope you enjoy the finished mower. 


SilverFox89 Sun, 20/05/2018

Happy to report that it's cutting great! Getting some stripes too, could not be happier. 


hillsider Sun, 20/05/2018

A nice restoration and a good finish on the lawn plus eco friendly as well - a good result all round.