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Collection, Preservation and Display of Old Lawn Mowers

First ever Restoration - Suffolk Super Colt - Lots of questions!

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Hello all, I've been browsing the site more and more recently - mainly from search results while googling for information. After giving up cycling recently due to health problems i needed something to help pass the time and something to fettle with! I've always carried out servicing and repairs on my own cars and bikes, learning along the way and reading up about things i didn't know how to do, and like to think I’m mechanically competent. 

There has always been something about engines that has intrigued me, and so i decided to see if I could strip down and refurbish a lawnmower. One came up nearby on the bay, a 'Suffolk Colt' which was advertised as spares / repairs due to 'No Spark - suspected coil'. I figured it was worth a punt and would be a good learning experience even if i can't manage to get it running. Looking online, Colt's didn't seem to quite match the look of my mower, which led me to discover it's actually a 'Super Colt'.

What started off as a simple 'Let's find out why it's not sparking' quickly resulted into a complete strip down of the entire mower and lastly the engine!! Taking plenty of pictures along the way, and bagging up nuts and bolts with labels so as not to forget what went where, I've now stripped the entire thing down so that I'm left with the engine block, and an exhaust that is well and truly welded to the block - thankfully it doesn't appear damaged, just rusty, so It can stay where it is (frustratingly for my OCD).

I'm going to test the waters here to make sure I can upload pictures properly, and once I can, I'll post up a few pictures I've taken during the strip down. I've come across quite a few things I’d really appreciate some advice with so anyone interested in looking/reading can hopefully help me out - which I’m hoping will help others out in future who are thinking of tackling the same sort of project.

Here is a Picture of the mower after collecting it

Forums

RedLeader Fri, 03/07/2020

My new spherical bush for the clutch shaft arrived, part L08501 (F016L08501) as well as some 1/4" shakeproof washers for my starter, in accordance with the parts diagram, as they were missing

Should this bush be soaked in oil before fitting? And the felt packing strip that surrounds it?

EDIT - Just read up about oilite bushes and there would be no point soaking it in oil, as the initial process of getting the oil into the pores is done under vacuum

Clive1962 Fri, 03/07/2020

That sounds such a familiar story....  at a local show some years ago there sat a 20" Marquis with a second, in pieces engine, turned out to be a failed rebuild which was assembled from more than one...had to correct the engine location, drill and tap.!!.. but turned out ok in the end...engine seemed sound but did valves etc,  started first pull but smoked to match the Red Arrows....  Turned out to be the oil control ring stuck in...all ok after re ring . The second sloper engine or  remains of it, was interesting as I believe it had a parallel crank rather than taper.?

Then I  was short of a grass deflector, at that time around £100-ish, so another machine was spotted in the local paper, at quite a price, but upon visiting found it had chassis cracks, sideplate tops by front of engine plate, known ailment, and a poorly carb mount, price genuinely reduced and came home with me to provide initially deflector plate..of course then I saw an 18" on e-auction, so close I couldn't resist....and then 2 came on a pallet from deepest Cornwall.....

Like I say..... ;)

C.

RedLeader Fri, 03/07/2020

It sounds like there's no hope for me then, once you've done one mower, it's a slippery slope(r?).....

At this rate I'm going to need a bigger garage/workshop as I can hardly move now - in what once was a tidy organised space! Already keeping an eye our for local donor machines just in case there are any parts I need for the Ransomes - I haven't even had a good poke around on either of them yet, literally just collected, managed to get both in the back of the Ford Focus, lifting out was much harder than lifting them in as they aren't light! and put into the garage awaiting a good lookover

RedLeader Fri, 03/07/2020

I might need some advice regarding the assembly of the rear roller. I took pictures during disassembly, and have the parts diagrams, but something doesn't quite seem right.

This is the diagram I am working from

and my parts 

Part number 7 - Bush for rear roller - I presume is already installed in each end of the roller, as per my last photo (Silver inner bush above) and I have the nut and spring washer for the non drive side, so that matches. However I have two very thin metal washers which were on this side before disassembly, can you can see here:

but these do not appear on the diagram on this side?

On the drive side, I believe I have the correct 'Thrust washer' - part number 6 - as per picture during disassembly

Part number 11 - Bush for rear pinion shaft - I believe is the bronze flanged bush which sits in the side panel, so that's ok. I have the nut and spring washer for this side too. However, the diagram shows parts 12 and 13 as Washer - Shim, each with a different part number. I'm not sure I have these as they look like they should fit behind the nut holding the pulley on. When i disassembled, I just have one very thick washer here, as seen on the left of this picture

The Suffolk Super Colt diagram doesn't show any washers on the non drive side either, so the 2 fitted on my mower before disassembly must be rogue? 

However, the Suffolk version strangely doesn't show any washers/shims between the outside of the pulley and the nut, but DOES show a spacer  - part 100 - between the pinion and shaft sub assembly, and the flanged bush for the pinion shaft, which the Atco diagram does not have

can anyone who has stripped one of these before help to clarify?

Clive1962 Fri, 03/07/2020

My tendency was in a ordinary service not to remove roller shaft from r/h side, same with cross member rod left in situ attached thru r/h side and then re assembly took place adding the roller, cylinder.  The deck plate went on towards the end of assembly..check and level..add bottom blade, then slide in delivery plate from top.

 The two washers on l/h side of roller are shims to take up end float, many had two.

 

C.

Clive1962 Fri, 03/07/2020

I found this, out of focus photos, on my pc taken when I must have been assisting someone with belt and guide settings some years ago.   Interesting also to see  Atco green remnants on chassis and Suffolk Super colt green on cylinder pulley..

 

C.

RedLeader Fri, 03/07/2020

Thanks again Clive, that's a big help. I'll leave the 2 thin washers on the l/h side to take up end float in that case and see how it feels when back together. From your picture, it looks like the same thick washer on the outside of the pulley under the nut that I also have, so perhaps this was a change at some point from the original 2 washers/shims in the Atco diagram. 

I definitely don't have washer '100' form the Suffolk diagram, and as it doesn't exist in the Atco diagram, hopefully it isn't required. 

Yes odd about the different Suffolk green on the cylinder pulley, that's exactly how my mower came to me. I couldn't tell if it was original or if someone had painted the pulley halves, so I removed the green from them and left them bare.  

I'm waiting for the cutting cylinder and bottom blade to come back from being sharpened and then I can start getting the 2 halves back together.

Going over to the drive side, how tight should the drive chain be set? Is there a specific amount of movement that the chain should have, say being able to move the chain 'x' distance away from the chain slipper?

Clive1962 Fri, 03/07/2020

I suspect a batch of Suffolks recvd overall  Atco green leaving internal components ex the Suffolk line.   

1/2" movement on the rear chain run was the word, just visible in Wristpin's earlier belt adjustment post...in reality chain wear has to be added to this rather than tightened to compensate against it and almost inevitably on a mower there will be a need to check carefully for tight spot.   What was then forgotten by owners was that cylinder adjustment over time, down onto the bottom blade, on these models sees the chain tighten as a result.  By the time machines came in for attention chains were often found to be dead tight...damaging tensioner, etc and even one on a relatively new machine had pulled the top shaft right through the top bush..how on earth they managed to keep running it to that point I couldn't see... 

By the time they came in for service they were eminently fixable and mostly easily so but often consumed a good few parts if the attention interval had been a long one.

 

C. 

Clive1962 Fri, 03/07/2020

I forgot to say...early Super Colt/Punch? had some detail differences one was that the rear belt pulley was alloy rather than pressed steel also the jockey pulley arm was alloy.

  The last ones and later production  Punch had alloy ring gear within the roller with matching nylon pinion drive...they had to be kept as matching paired items.  

C.

wristpin Fri, 03/07/2020

The second sloper engine or  remains of it, was interesting as I believe it had a parallel crank rather than taper.?

Slopers were a general purpose industrial engine and  not exclusive to Ransomes and in non Ransomes applications usually had parallel shaft cranks, and often red fuel tanks and shrouds.. One that comes to mind was on Pattison ( Paterson?) spikers; a gruesome  bit of kit !  Also remember them on concrete mixers.

Clive1962 Fri, 03/07/2020

Thanks for the info on the sloper, I never got to see them in other applications.   This one had, I assumed, a Ransomes clutch backplate but not of the large flywheel type...but was minus head, shroud, tank, etc..

C.

Clive1962 Sat, 04/07/2020

Just checked this morning....there is a steel spacer behind the steel pulley, appears, on quick visual, to be same as one in front of pulley...I feel I should have known that, but didn't often remove pulleys....  Here's one of my blurry photos, taken a few mins ago....shows the mouse droppings  too ;)

C.

RedLeader Sat, 04/07/2020

Interesting info on the sloper engine Angus, and thanks for the document. I've been working form a slimmed down version of that one which just has the 12" Standard diagrams. 

Clive - that's a big help, thanks very much for the picture! That clears up one of the extra thick washers I have on the side as my original pictures didn't show that one behind the pulley. I thought I took enough pictures when taking things apart, but clearly not!

Oh and thank you for the advice on the chain tension too. I checked all the links of the chain when cleaning it originally and thankfully there are no stiff links, so I will give it a grease up ready for fitting, and remember to check the tension once the cylinder to bottom blade adjustment has been carried out :)

Clive1962 Sat, 04/07/2020

Pleased that you've located another matching spacer washer. :)  I checked again here and both do appear to be the same size, front and back of pulley.

 I've been pondering...and I bet in the early days when it was an alloy pulley with a longer central boss it had a thin "shim" like washer behind and a flat washer in front.?   I have 3 others chassis I could check but they aren't accessible at present.!...but my Atco version looks totally un molested, although very worn in many places it didn't look as if the pulley had ever been removed looking at grease markings on one side and fresh clean steel on the other of the back washer.

I feel it may be another place were a little artistic licence may have crept into the parts diagram.? and has lagged behind a production change.?  

There are likewise on mine 2 shim washers on the non drive side roller..

I did find online a diagram for the Webb Diplomat 300 which was really the last use of the Atco Standard type of chassis/handles/fuel tank.   A nice useable machine which we sold a couple of in preference to the Punch 30S of the day, in the very last days of the machinery agent I once worked for...30 years ago now.!   I wouldn't mind acquiring one for old times sake :)  The Diplomat drawing still showed 2 "washers" outboard of the pulley..but I couldn't access the section which gave the part no.s to check further.

 

C.

RedLeader Sat, 04/07/2020

Interesting, thanks Clive! 3 other chassis, sounds like you've got plenty to keep you busy?! Are they all working, or are they for spare parts/donors/waiting to be brought back to life?

I hadn't seen a Webb Diplomat before so had to look up some pictures on the web, and I see the similarities: ) In fact, the handles and petrol tank look strikingly similar to those on my mower?? Out of interest, are the handles and petrol tank on your Atco the same as mine or are they different? It looks like I might actually have a 'Webb' addition to my mower...

Clive1962 Sat, 04/07/2020

The handles on mine are the same as yours and correct for the Atco type.

 They could have been consigned to history but  the design was utilised again in the build of the Diplomat.   At the same time there was the Atco Ensign which was the similar basic chassis but with a loop type handle and other higher spec fittings.   Right at the end of this chassis type the clutch changed...it was after my time in the mower world and have never set eyes on the later ones..but I understand that the centrifugal clutch was replaced by, I assume a belt clutch in the l/h case. ? so there was then a control cable entry point at the top rear of what would have been the chain case originally...all changes would be driven by the machinery regulations applicable of the day.

 I have to admit that my machines are largely sat waiting for....one day I'll ... so currently just feature in my reminicences of old times...which has been amazingly helpful in keeping interest in things during recent months....   

 

C.

 

Here's the Ensign...and another possible explanation of how grass boxes can fail over time...

wristpin Sat, 04/07/2020

Your non folding handle and mid mounted tank are correct for the Standard.  The De Luxe had folding handles and a different pattern of tank, as shown on the last page of the Dropbox parts diagrams that I posted this morning.

If nothing else, Atco, Suffolk, Qualcast and Webb had badge engineering off to a fine art and their parts inventory was put to good use across the brands.

Clive1962 Sat, 04/07/2020

If nothing else, Atco, Suffolk, Qualcast and Webb had badge engineering off to a fine art and their parts inventory was put to good use across the brands.

..and just a few of the parts lived on and still do on the next style of machines....and crossed over in earlier times to..or from..the Atco roller rotary mower...

 

RedLeader Sun, 05/07/2020

Lots more interesting information, thank you both very much. I'm sure the Atco manufacturers didn't plan on mower operators using the grass box as a stool, even the 'impact resistant' versions! 

Glad your machines have been helpful keeping interest recently with these strange times Clive, hopefully other's have found the same, I know I certainly have. 

The end of the sanding/prepping/priming/topcoat is in sight thankfully, just the Atco green colour waiting to go on the chain case cover now. I've managed to get the majority of the dents and bumps out, so hopefully it comes up well. Then I'm at a standstill until my cylinder and bottom blade come back. Which gives me the perfect opportunity to try to fix the fuel leak on the first of the 2 Ransomes which other than that seems to work well, and which will be my regular use mower hopefully, while I look at fixing up the other one which has no spark. 

RedLeader Fri, 10/07/2020

After cleaning up the cylinder and bottom blades, I sent them off to be sharpened and painted - nice to see a contrast to the green at last :)

which meant I could finally get it all back together...

It's beginning to look a lot like... a lawnmower...

Which brings me to the clutch adjustment. Getting a little frustrated here. I've followed the guide which Wristpin kindly uploaded a picture of, which says to allow approx 5/64" gap between the top of the metal belt guide with the clutch disengaged. I've set the barrel adjusters at both ends of the clutch cable to the slackest position. However when I push the mower forwards, the belt is putting too much drag on the front cylinder pulley and therefore turning the blades. If I push the mower backwards, the belt slips around the rear roller pulley fine. I have the 2 washers in between both halves of the front cylinder pulley to widen the V groove, but have also tried them on the outside behind the nut instead, to bring the 2 pulley halves closer together, but the same happens. I've now removed the belt guide completely to take that out of play, however the same happens. The jockey pulley is in the slackest position, resting on the bottom

So close yet so far - can anyone suggest what could be going wrong here - I haven't replaced the belt, so can't rule out it's the wrong belt... Also if I hold the mower still, and turn the cylinder carefully, the belt slips like it should....

hortimech Fri, 10/07/2020

Fit the belt guide! If this doesn't fix it, remove the cylinder nut, washers and the outer pulley half. Place one of the thin washers on the cylinder shaft and refit the outer pulley half, followed by the remaining washers and the nut.

RedLeader Sun, 12/07/2020

The belt guide was fitted when the issue was present, therefore I removed it in case it was causing the excess pressure on the belt - it wasn't, as the issue still persists without the guide. This is why it isn't in the pictures above. 

There aren't any markings on the belt at all, so I've ordered a correct vee belt (L08476) so at least it rules the belt out if it still does it. If this doesn't cure it I will play around with the config of the front pulley shims as suggested.

Cable clips - for holding the clutch and throttle cables to the handles - L11580 - seem to be available, however postage is considerable so I will wait until I need to order some other parts! Given the rest of the mower, seems a shame to use electrical tape or cable ties!

wristpin Sun, 12/07/2020

If the belt is a genuine part with that or the later F016 prefix it should be fine but many suppliers may send a pattern belt with perhaps a Z prefix . The problem is that that some suppliers matched to slightly different sizes .  If the belt that you receive has sizing markings as opposed to just a part number, and it does the trick , share that number with the forum. Meanwhile I’ll have a look at some of my old paperwork !

Put the guide back on, as all other things being correct, it plays an important part in springing the disengaged belt from away from the pulleys. Rule of thumb - with the drive engaged the guide should not touch the belt either top or bottom . Disengaged it should spring the belt clear of the back puller - clear being just enough slack for a rust free pulley to slide , not a huge gap.

I’ve not got a machine to look at but I’m surprised that your tensioning roller appears to be pressing quite hard on the belt while at the same time is resting on the flange of the chassis.

Clive1962 Sun, 12/07/2020

Here's a photo of my machine...with tensioner disengaged.    Earlier up the thread is the same machine with pulley shown lifted, to statically, simulate the position that it would be in when in drive, with the top guide just clear of the top of the belt.    

 My machine will "freewheel" ok and cylinder turn freely too, one shim in between the pulley and one as "washer" behind the nut.

  It is set up, on cut, and has a brand new bottom blade fitted which will have restored the cutting cylinder to a relatively high position within its potential travel...  

 

C. 

RedLeader Sun, 12/07/2020

Thank you both very much for the advice. I will be sure to post once the new belt arrives detailing the size/numbers if it is successful. 

I've refitted the belt guide - here is a picture of the clutch disengaged, and then engaged

So the belt guide prevents the belt from resting on the jockey wheel (as seen in previous picture) and making it look as if the jockey wheel is deflecting the belt with clutch disengaged. I've set the gap so that when disengaged, the belt has the required clearance and doesn't touch the top of the belt guide, but the bottom of the belt rests on the bottom of the guide. 

With the clutch engaged, the belt is completely clear of the belt guide so no problem there. There's just slightly too much friction between the belt and pulleys with the clutch disengaged. 

The belt does sit on top of the pin beneath the rear pulley, when the clutch is disengaged - is this pin there just to prevent the belt from coming off of the rear pulley? (circled white)

wristpin Sun, 12/07/2020

I was referring to the image in your post 324 which seems to be at odds to the ones that you have just posted. Basically the correct adjustment with the correct belt is a trial and error process rather than a by numbers one. As you are finding out, there are a number of variables and Clive has just thrown in another - the position of the cylinder - except that becomes a fixed point that the others have to relate to. Wait and see what a new belt achieves. 

Clive1962 Sun, 12/07/2020

The belt guides keep the belt in shape, around, but just clear of, the pulleys when out of drive...allowing the pulleys to rotate free of the belt when out of drive. 

Without a guide, to keep the belt in shape, the belt would drop into the pulley and catch, in one spot, and thus snag the belt into drive. 

The front guide is adjustable because, with blade/cylinder wear, the position of the cylinder shaft and thus the pulley will change during thje working life of the mower.

The back pulley guides, the pin and "pip" at the top in the casting, are fixed position relative to fixed location of the back pulley.

C.  

edit, to add that Wristpin, posted whilst I was still typing...he's faster at typing than me ;)   Yes, wait and try again with the new belt :)  I ordered a new one for stock and it has come as Z 19.5, 10x500Li..but I add that I haven't tried it as yet as old one proved to be ok..at the moment.

RedLeader Sun, 12/07/2020

Ah yes, the picture in post 324 didn't have the belt guide fitted at the time, as I had just removed to test if the issue was still present, so the latest pictures show the difference having the guide fitted makes - i.e lifts the belt up off the jockey wheel when the clutch is disengaged. I can certainly see all the adjustments that play a part now, after setting the cylinder to bottom blade clearance, then drive the chain tension. Thanks both for the explanation, hopefully the new belt achieves the desired result after rechecking all the adjustments. I've noticed it is much easier to drag the mower backwards without the clutch engaged, than it is to push it forwards. It takes a fair bit of effort to move forwards, which is completely transformed by removing the belt, it moves totally free then, so definitely too much drag form the belt, as if it's on the small side.

hortimech Sun, 12/07/2020

It looks to me as if the guide is slightly high, there should an equal distance between the top and bottom of the guide and the belt. If this doesn't help, try spacing the cylinder halves apart with the thin washers, it is why they are thin. This does always depend on the cylinder being set correctly.

If, after checking and adjusting everything, it still will not push easily, then you will need to replace the belt.

wristpin Sun, 12/07/2020

I ordered a new one for stock and it has come as Z 19.5, 10x500Li..but I add that I haven't tried it as yet as old one proved to be ok..at the moment.

Ha, don't know about the typing, strictly a two finger job! However, just to confuse things, my crib sheet of many years ago for F016L8479 says Z19  - not really what any of us needed to hear at this stage.

Back to the waiting game. 

RedLeader Mon, 13/07/2020

Thanks Hortimech, Angus, Clive. I'll do some more fettling with the current configuration of belt guide and washers while waiting for the new belt to arrive, and see if I can obtain the desired result.

Angus your part number F016L8479 doesn't seem to return any results online, which is unusual as there is normally some sort of reference to at least most Suffolk/Atco part numbers I've searched for in the past. Tried F016L08479 as well just in case but still nothing. 

Until the belt arrives, just a few more update pictures

Chain case cover looking a bit better

RedLeader Mon, 13/07/2020

That's right, that's the number I've ordered - should be here in a couple of days :)

Henno Tue, 14/07/2020

Those pictures almost hurt my eyes... that mower looks probably better then it came out of the factory 30 odd years ago. And you should tell us something what you use to make those pictures... a feast for the eye. I assume not a 60 pound smartphone?

RedLeader Wed, 15/07/2020

Those pictures almost hurt my eyes... that mower looks probably better then it came out of the factory 30 odd years ago. And you should tell us something what you use to make those pictures... a feast for the eye. I assume not a 60 pound smartphone?

Hopefully your eyes have recovered a bit now Henno, sorry about that :) I completely understand that the mower will not be to everyone's tastes, but I'm happy with the way it has turned out, so far, having never done anything like this before. Compared with the sorry state it came to me in! The pictures are indeed all taken on my smartphone :) admittedly not a 60 pounds phone, but a Samsung S10 (I think?!) which does have a decent camera for a phone - have to keep a clean rag to hand for wiping oil from the lens though :)

RedLeader Wed, 15/07/2020

So, the new belt arrived, markings as follows

Certainly a bit longer than my current belt and also the V isn't quite as deep

I've played with every combination possible with the washers and adjusted the belt guide in tiny amounts and tested pushing the mower back and forth. Although certainly better than the previous belt, and it does now slip on the pulleys, when pushing the mower forwards, it squeals like a pig! The belt is squealing on the rear pulley about once per revolution of the pulley. Admittedly with the engine running, you wouldn't hear it I expect, but still, it shouldn't be dragging that much surely. There is rather a lot of end float on the rear pulley / roller gear pinion shaft, when I take the rear pulley off you can push and pull the pinion shaft quite a distance, but I believe this is normal and required to prevent binding? There's also a small degree of lateral play in the rear pulley when on the shaft and tightened up, which would appear to be slight wear in the bush for the pinion shaft - could it be possible that this slight play is the reason for the belt squeal/howl? This is surprisingly turning out to be one of the more frustrating parts! I'm going to have a break from it and get the clutch cover back on and then apply the Royal crest decal.....

Clive1962 Wed, 15/07/2020

Interesting that the pattern parts supplier I went to online sold me Z19.5....  I subsequently remembered I still had an old Central Spares catalogue lurking under my pc table here...It lists M19 / Z510...   I have to add that I'm unlikely to check my belt fit for a little while..whilst work calls.. 

 C.

RedLeader Wed, 15/07/2020

Hmm I think you've probably got the correct length belt there Clive, a Z19.5 (19.5" inside length) would probably give that extra bit of slack required on this setup, based on all the (now extensive!) testing I've done. It would probably also allow the jockey wheel to have some pre-tension on it to move it up from the casing floor just slightly while the clutch is disengaged, so as not to clatter. I think I'll get one ordered...

Clive1962 Wed, 15/07/2020

Your new belt though does tally to that which Angus had on his workshop crib sheet, which I'm sure will have served him well.

 I wish I could have retained more documentation from my old work place, I had a few duplicate parts books come home with me but suspect the rest were discarded in the clear out back then...lots of the parts books behind the counter had hand written in updates for such as belt and bolt sizes etc.

C. 

RedLeader Sat, 18/07/2020

I wonder if Z19 is correct then, and perhaps after a bit of running in the belt will be fine. I will post back as soon as the Z19.5 arrives and I can do some testing with that.

In the meantime, running through some last checks before I try and start the thing for the first time - issue discovered with the fuel tap. Nothing was coming through the tap and after removing the plunger, the cork was stuck inside the tap body! I managed to fish it out and the cork looks fine, however I don't understand how it's supposed to stay in place on the plunger, as there is nothing to stop if from coming off of the end? Is the plastic normally splayed a bit at the end to prevent the cork coming off?

RedLeader Sun, 19/07/2020

Curious how an original one of these retains the cork, but soldering iron it is! The cork seems a bit short based on the position of the fuel entry port, so needs packed out at the back to keep it far enough inside to blockage port when closed. 

Packed out with a nut, and the soldering iron created a retaining end. Or so I thought - due to the tight fit even with the cork not swollen, it became stuck again and the plastic retaining end piece snapped. Going to look online and see if I can source a new plunger style tap, the same as this, but doesn't look likely - I may have to opt for the lever type instead....

Jonson Mon, 20/07/2020

In my experience the lever type fuel taps are usually more reliable than the plastic plunger ones, especially if you're planning on using the mower a lot, however I have to say yours looks far too pristine for that! 

Best of luck with the first start (don't forget to check oil level). Can't remember if you replaced the rings or not but if so it's best to take it easy with the revs at first.

RedLeader Tue, 21/07/2020

Thanks Jonson! Fresh oil level is spot on, and I nearly had to check the thread myself, if feels that long ago, but yes I did fit new rings :)

Some updated findings regarding the drive belt. I ordered a Gates belt in Z19.5 out of curiosity (493/515 L)

Immediately much easier to get the belt on and in place, and I could easily push the mower back and forth with no resistance or belt squeal. At the same time, squeezing the clutch lever did not produce enough tension on the belt to drive the roller, and resulted in more squealing but due to being too loose this time! I adjusted the clutch cable at the mower end by unscrewing it approx 2/3 of the way out and locked it in place. This raises the jockey wheel up enough to put a fair bit of tension on the belt, but seems to be the perfect amount, as I can push/pull the mower fine, and with the clutch engaged, it drives the roller properly with no belt slip or squeal. 

All this means is that there isn't a huge amount of adjustment remaining to cater for cable stretch in future, although there is also the adjustment at the lever end of the cable, so actually it's probably fine. Whether other mowers of this same model require a Z19.5 belt it's hard to say, it could be that the Z19 belt might be ok after it's actually been used properly, as it might free up just enough to not cause issues once it's broken in a little, and then you would have the entire adjustment length of the ferrule in future. Either way, happy to have found the sweet spot in terms of setup for my mower at least. 

Clutch disengaged

wristpin Tue, 21/07/2020

Looks as though you may have both spacing washers out of the front pulley but if there’s one still in there , you could try removing it and maybe regain some potential cable adjustment, but even a new cable isn’t going to stretch that much.

RedLeader Wed, 22/07/2020

That's a good point, I think I'll leave it as is due to it working as desired now, but if there is any stretch in the cable, the remaining washer can come out from between the front pulley and go under the nut with the other one. 

I'd like to say a HUGE thank you to all who have followed this thread and who have contributed such valuable advice and guidance. I honestly couldn't have done this without the kindness and vast wealth of knowledge of the members of this club - Angus, Hortimech, Chris, Clive - to name just a few! I hope others can benefit from all the advice given here should they wish to tackle something similar themselves. I can hopefully help to pass on some of the advice and knowledge I have gained to others members who post questions up in future. 

One forum member came up trumps and kindly helped me out with a replacement petrol tap which I have just fitted and it works like a charm :) - I am now 99.9% complete with this restoration - here are a few pictures of the finished article