Ransomes Ajax mk3 advice; paint & rollers

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Nigel
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Ransomes Ajax mk3 advice; paint & rollers

Could anyone help me on a couple of issues with an Ajax I got recently?

First, although I'd like to re-paint it in its original colours, essentially, I bought it to cut the grass. Is the Tractol paint I see on eBay good quality or is there a better alternative? (I'd be hand painting rather than spraying.)

Also on the issue of colours, all the pictures I've seen have the blades painted red. The whole blade cylinder on mine is very definitely the same green as the bodywork. Is this odd?

Secondly, I dismantled, cleaned and reassembled it. (I went as far as the rear roller and the blade cylinder bearings; I lost my nerve at that point because I was worried about finding my way back.) However, I'm concerned about the gap between the two sections of the rear roller. I can't remember what it was before I started and it looks "wider" than I've seen it on some pictures. It's max. 22mm, min. 15mm. Is this as it should be? - and how do I adjust it if it's not?

Finally, the grass box is reasonably sound but it has a few dents and some surface rust. I can clean it and tap out some of the dents but, if I wanted to treat it to a new "by appointment" decal, how perfect would the surface have to be for one to "stick" properly?

I would be very grateful for some advice.

Brad
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Hi Nigel, I am also restoring

Hi Nigel, I am also restoring a MK5 to actually use. 

I have a MK3 body if you need any parts and are near Gatwick.

I'm painting mine in Hammerite garage paint.......... don't tell anyone!.

I've had the cylinder and bottom blade sharpened and painted both red (Hammerite).

Ordered a decal from Australia which is good but that was before I joined the club and found they sell decals on here also.

Had some new oak front rollers made, two small and two large.

But the most helpful thing to date was Clive giving me some of the parts I needed and downloading the schematic from the club for free.

I've been stripping paint and rust off with wire wool, wire brush and wire brush drill fitting.

Progress has halted as I have bee hives to build and the weather has gone a bit poo.

Nigel
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Brad, thank you for your help

Brad, thank you for your help! Your project seems well advanced.

The main "problem" I've got is the size of the gap between the two rollers. I've looked at dozens of Ajaxs on the internet but I've only seen about three with a similar gap. 

All the others, including one in a museum, seem to have the rollers very close together. On mine the gap is 22mm max/15mm min.!

I can't see any way to adjust it. 

Can you - or anyone out there! - give me any guidance?

(I'm afraid any fun jobs like the re-paint and transfers will have to wait until I've got this mechanical problem fixed!)

And thanks for your very kind offer on parts; much appreciated!

Nigel

 

 

 

Harvey
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The roller gap.  I believe

The roller gap.  I believe that the MK3 is the same as the 4 and 5 in this respect. I do not know exactly what the gap should be but looking down between the outer ends of the rollers and the side plates you will see a square headed set screw which is threaded into the 'ratchet / free wheel hub' and bites down onto the axle and retains the rollers in position.  Slackening this setscrew should allow you to slide the rollers closer together; in theory anyway.  It is quite likely though that the screws will have chewed up the shaft; probably having come loose at some time and you may have to dismantle the mower to free the roller hubs.  Several people here have stripped and rebuilt Ajaxes so advice should be on hand if you need it.

hth Harvey

Nigel
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Thanks for your help, Harvey.

Thanks for your help, Harvey. I think I'm getting into deep water here! 

I've removed both of the square-topped screws that clamp down onto the axle but, as you suggested, neither of the ratcheted bearings (?) moves. 

With a well- padded Mole grip, I managed to turn one of the bearings (at the non-gear end) without too much pressure, clockwise. After a few gentle turns, the bearing has moved inwards - to the point where the flat on the axle, that I believe is supposed to be the seat for the square-topped screw, is partially exposed.

What I cannot do is find a way to draw the bearing outwards. I can't find any way to pull it towards the end of the axle.

So, using another well- padded Mole grip to hold the axle, I managed to turn the bearing anti-clockwise - but is hasn't come back outwards.

Apart from an annoying score-mark on the bearing when the grip slipped, I don't think I've done any damage - yet! In fact, I've managed to close the gap! - right result for the wrong reason since an excess of adjustment has taken place at one end instead of a bit at both! It can't stay like this.

I'm sorry to impose on your time when I've only been a member for five minutes, but I need a bit of help here!

Nigel

 

Harvey
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Nigel,

Nigel,

My opinion is that your best option is to dismantle the mower in order to deal with the problem. You may cause further damage otherwise.

There are several 'threads' here about rebuilding Ajaxes which contain useful dismantling tips. It is not really very difficult. To give you some encouragement this is a mower that I gave a 'drink' for.  The owner had some trouble with the land rolls and tried to fix it with a sledge hammer.  Do not do this!

Before and after pics.

Harvey

Brad
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Nice resto Harvey, I'm not a

Nice resto Harvey, I'm not a fan of the silver though, I think I'll be going green and risk being lynched by the purists!.

Sledge hammer!!! really, I'm amazed it didn't break anything.

Nigel if your anywhere near Gatwick like I said before I can give you some spares for free, in all fairness I removed mine with a rubber mallet and yes the grub screws had damaged the shaft, but I've four mowers in total so finding a nice one to use shouldn't be an issue.

I am going with little or no gap my self, but I've not even finished cleaning the bits I intend to use yet.

If your more down towards the coast contacting Clive at the south downs heritage center was very useful, especially for my spares. 

Nigel
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Thanks again, Brad and Harvey

Thanks again, Brad and Harvey, for your advise and encouragement!

I've actually managed to get one of the "ratchet assemblies" off the rear roller axle (I haven't started on the other - yet). I read the earlier posts and it seems to be a common problem. I tried some heat and a few taps with a mallet but I'm worried about collateral damage so I went back to yesterday's approach; turning it with the Mole grip. This time, I made up a wooden cradle, put the gear wheel back on and clamped it in the vice. This held the axle so that I could turn the ratchet assembly in the other direction. With plenty of padding and oil, I turned the assembly and it gradually moved outwards to the end of the axle - and off!!

The axle and the inside of the assembly is scored - so much so that I thought at first it was threaded and that the assembly actually screwed on and off! I've cleaned it up and given it a light rub over with very fine wet/dry. With a good bit of grease, it goes back on and off reasonably freely. 

I've more to do on it because I think the scoring is actually what's now stopping the roller sliding off the axle, but it's a start and if it were not for you gentlemen, I'd still be sitting staring at it!

(I know these are beautifully designed machines but it does seem that that little screw, tightened down onto a fairly shallow flat, is being asked to do a lot! - holding that assembly from turning.)

Thanks again for the the help on spares. Unfortunately, I'm up in Northumberland! - where the usual way of dealing with grass is sheep.

Nigel

 

 

 

Nigel
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The continuing saga of

The continuing saga of getting the ratchet assemblies off the roller axle! (I'm sure that most people out there have been down this track before but, in case there's anyone newer to lawnmowers than me, perhaps these pictures can illustrate why these things can be so hard to get off!)

I got both off by gently turning the assemblies with a well-padded Mole grip; they traveled towards the axle ends, and off, as though they were a screw fitting.

The first one (the non-gear end) was scored on the axle by the squared-top retaining bolt. The scoring on the axle had, in turn, scored the inside of the assembly. With a bit of wet&dry paper, I was able to clean up the surfaces and get the assembly reasonably free on the axle.

But on the second one at the gear end! - the scoring was dreadful!

Over the years (?), the assembly, in spite of the retaining bolt, must have turned on the axle, dragging the retaining bolt with it. The base of the bolt must have moved out of the "flat", that it was originally screwed down on, and carved a channel around the axle. The steel from this channel was pushed up into "walls" on each side of the channel which, being harder than the aluminum of the assembly, cut deep grooves in it.

These walls and grooves are, perhaps, why in this case, it would have been very hard to hammer the axle through the assembly to get it off. (I am pretty sure that none of the scoring has been caused by my removal of the assemblies.)

I cleaned off the "wall" ridges on the axle and smoothed the assembly tube and they seem reasonably comfortable now.

Interestingly - to me anyway! - the distance by which each assembly had moved outward over the years, towards the axle ends, explains the over-sized gap between the rollers that I was moaning about in the first place!

I still have a couple of questions:

- what grass cutting action could put such pressure on the assembly/axle connection to cause such severe metal-to-metal damage?

- why would the "travel" of the movement be in an outward, "screw" form? - and not just "round and round".

- if it's happened once, how do I stop it happening again???

Re the first, I've tried to visualize what happens when the mower's being used. If the rollers are being pushed and turning the blades, and the blades were suddenly jammed by,say, thick grass, would the full pressure of the "push" be transmitted to twisting the assembly on the axle?

The other two, I don't have a clue!

(I haven't got the hang of uploading pictures! - the first is inside the assembly, second & third - the axle (all from the gear end), and last the two retaining bolts.

 

 

 

wristpin
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These things happen and once

These things happen and once reassembled, out of sight and out of mind - almost!

Careful reassembly, line the screws up with the flats and use a drop of Loctite to make sure that they don't slacken off.  

Nigel
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Thanks for the tip about

Thanks for the tip about Loctite. Because the edges of the flats have been stripped away where the retaining bolts have "escaped", I had been considering carefully drilling a, say, 1/8th inch deep "seat" into the flat, of exactly the same diameter as the bolt, to act as a retaining "cup" to stop it moving again  - but that might have been a bit drastic!

Nigel

wristpin
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Not drastic at all imo, but a

Not drastic at all imo, but a practical solution to what you are faced with - just make sure that you drill in the right place !

In some similar situations the bolt will be manufactured with a slight taper on the tip that locates into a depression of a lesser diameter than that of the threaded part of  the bolt.

Nigel
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Thanks for that, Wristpin. I

Thanks for that, Wristpin. I think, on balance, I won't make my proposed "modification" to the retaining bolt arrangement on the roller axle; it could potentially make things worse.

It does seem that the scoring on the axle, and in the barrel of the ratchet assembly, is caused by the end of the retaining bolt being driven - a very little distance each time - around the axle by the rollers when a sudden Stop! of the blade cylinder (ie unable to cut through the grass or caught on a large twig) transmits a sudden Stop! to the roller axle but the little retaining bolt's pressure on the axle, which is supposed to lock the axle to the rollers, is overcome by the forward momentum of the rollers - presumably because of the bloke still pushing them!

If I made a deeper seat in the axle for the retaining bolt, it would probably make any slippage between the axle and the rollers a lot harder but, if the blades continued to jam, isn't it possible that, over time, instead of the retaining bolt scoring the axle, the end of the bolt itself could become distorted? If that happened, it would be impossible to unscrew the bolt. Curtains!

I expect Ransome's solution would be "keep the blades sharp, the heights properly adjusted and don't try and make the mower do what it's not made for!"

Sorry to grind this so small!  That's it.

wristpin
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I think that considering

I think that considering Ransomes' over-engineering your scenario is unlikely but I respect your decision. Just enjoy your machine.

hillsider
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I think if you reassemble

I think if you reassemble carefully and tighten the screws fully then all will be well, sometimes we tend to over think problems such as you have experienced.

The root cause of the problem was likely to have been the screw becoming loose either by backing off due to vibration or simply not tight enough when last assembled. I also think you are wise not to drill out a recess for the screw to locate in if you are lucky the marking on the shaft will engage the end of the screw in somewhere near the correct location for keeping the rollers together.

As Wristpin says enjoy the machine.

Nigel
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Thanks, Hillsider. It's

Thanks, Hillsider. It's reassembled now and looking good. - now onto the painting! 

Nigel
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Thanks, Hillsider. It's

Thanks, Hillsider. It's reassembled now and looking good. - now onto the painting!