[sidevalve5]

Dear Charlie,

That would be great. Have a Clifford Mk IV and a manual which I think has an exploded view of the machine. But the Mk 1a is a very much cruder piece of engineering. Believe the Clifford factory made parts for the MoD in the war and probably rushed to get a roteo on the market soon afterwards. The Jap 5 engine was made in 1948. So do not have a clue if the oil seals in question are the same for both models. In all probability think they would have been improved upon. Be good to know how to take it apart and what the fix is for the leaking problem. Suspect the ID and OD of the original seal may not have a modern equivalent.

Best wishes,

Grahame

[sidevalve5]

Hi Norman,

You may be able to help me. I bought my Clifford 40 years ago and got a Trusty at the same time. A chap was giving up his ground and wanted to clear his sheds. Used both for a few years, the Trusty had the better engine, but the transmission was knackered. The Clifford was hard to start, but the hooked tines did a really good job in seedbed preparation. It had a massive oil leak where the bevel drive housing joins the rotor axles. Someone told me it was a common fault when the machine gets old because the oil seal was, I think I recall him saying, leather. Which dried out and wore. I used to have to store the machine tilted with the engine on the ground, otherwise it would loose all the oil. Still had to give it a good top it up every time I used it. I put some new tines, big end shells and rings on it, all purchased from Chester Hudson. Then moved and put it away in a shed, ready for the day I had the time to carry out all the repairs to make it a reliable machine again. Two years ago my Trusty Jap 5 engine blew the big end. So I took the engine off the Clifford and made one good engine out of the two. Still have another spare engine, so the plan was to fully re-build that one and fit it to the Clifford.

Where you can help me is with advice about the dismantling of the rotor axles and what I should expect to find in the way of oil seals. Then how to get the parts to fix the problem. Like yourself, am in no rush to do this. At the very earliest it will be a couple of years before I get round to doing it. Have another couple of working rotovators I have done up, so there is no pressure to fix the Clifford.

It was a right old beast to use, no throttle, just the governor to regulate the engine speed. When you pulled the dog clutch handle to engage the rotor you had to do the same for the drive with the next movement of your hand. Otherwise it tried to jerk out of your remaining hand on the handle bars. Was younger, fitter, stronger and quicker back then and it still took some effort to use. Remember I could not get it to start one day with single swings, so kept winding it up as fast as I could. It fired, the handle came out, swung around and hit me straight in the mouth. There was blood everywhere. All good fun though.

Best wishes,

Grahame

[sidevalve5]

Hi,

I have the same machine in its original colour. Have taken the engine off, so some non faded paint is now exposed. Will take a photo so you can colour match if you wish. But this may take a few days, the machine is buried at the back of a shed. Some experts in the club may be able to help with the exact colour from a previous restoration.

Best wishes,

Grahame

[sidevalve5]

Dear Roy,

There is not much to them, so expect you will be able to work out what goes where quite easily. But if you do get stuck, send a photo and I will try to help. Can dig my machine out and take some pictures of a particular part if you wish. The throttle linkage is a bit crude, the chains are very slack and the gearbox is full of false neutrals. But it still works very well for light skimming. It does struggle on hard ground or with big weeds.

Best wishes,

Grahame

[sidevalve5]

Dear Roy,

I have the same machine in original condition that I still use for row cropping. I do not have a manual, but can take some photos of any individual parts of the machine that you are unsure of, if this helps. Think you will find the engine is a JAP 2a, not 1a.

Find the Colwood a joy to use, much easier than a Planet type push hoe that would be the usual alternative. You can go very slow in 1st gear if you want to be very accurate and get close to the crop. Or nip along in 2nd. The clutch on mine sticks after it has been left for a few months, but rocking it back and forth soon free’s it. Had always assumed the steel wheel was fitted as standard on the eariler models and the rubber tyres to the later ones. There are many experts in the club with access to documentation that could clear up this point for you.

Best wishes,

Grahame

[sidevalve5]

Hi Paulr,

Its a bean seed planter, used for sowing larger seeds individually. Do not know the make though. Have little experience of them as I have never used or worked on one. Hope this helps.

Best wishes,

Grahame

[sidevalve5]

Had a similar problem with a Kohler K181 engine after inspection when I took it apart. Got a rebuild kit from the USA with an oversize piston and struggled to find an engine reconditioner that would do the rebore. They had the machines set up for large engine blocks and one said just breaking it down and setting it up for a small block would take the best part of an hour. But did eventually find a chap at Kidderminster who does them. You may have to make many phone calls, but will find someone somewhere. A tip maybe is look to see if they do British motorcycles, there are several in the West Midlands. The Kohler rebuild kit only cost about £70 and was a bit sceptical if the parts were of reasonable quality. Should not have feared, they were fine, with ideal limits and fits tolerances. Have a mate with a Honda GX160 on a Merry Tiller that smokes like a steam engine and runs terrible. Am going to take that apart this winter and if the bore is within service limits, will get an after market rebuild kit for that too. Can you believe they are less than £20.

[sidevalve5]

Brilliant advice, especially about water getting into gearboxes. Have a Toyota Hiace and have to have the gearbox oil changed every year because it has water in it. No one who has looked at it could understand the reason why, but now David has explained it. As air cools it becomes denser and reduces in volume. Its why the float contracted then crumpled under severe cold and water around the Hiace’s gearbox was drawn into it. Have seen it as low as -14oC on more than one occasion. On a Zenith float would try to pull out the creases with heating, but if that did not work, de-solder it and knock out the dents from the inside. Or go to Villiersparts and buy a new plastic one. If I ever get a float thats just leaking and not malformed, will follow David’s method.

Many thanks

Grahame

[sidevalve5]

When I have recovered carb’s that have been left outside for years, found the opposite affect to expansion on the float. Some have crumpled due to the action of contraction in extreme cold. Put one into a cup of boiled water to see if it would recover its shape, but bubbles came out instead.

The ultrasonic cleaning did improve the Zenith’s performance at tickover on the Jap 5, but it was not perfect. After looking at the sectional drawing of the carb, I just get a feeling that some of the blind passageways still have a partial blockage due to corrosion deposits leaving an uneven surface.

Finished scuffling with the diamond feet yesterday using the new Jap 6 Trusty, it went like a dream. Raining this morning, so am sorting out a shed to fit it in. Will not need it now until the December ploughing. Now have a reserve gear can back it in, can even move it around on a hard surface because of the rubber tyres. Its a different world to the old steel wheeled Jap 5 Trusty. Used to leave that outside all year under a steel bath, just like most of the Trusty’s were kept around the Vale of Evesham. Gong to dig out the Davis toolbar this morning to use as a counterweight on the Trusty. Wonder if anyone had heard of one and know what it is.

[sidevalve5]

Think before I use something I am not sure about on a carb I will trial it with some scrap material. Some carbs are made from different alloys, so need to be careful.

[sidevalve5]

Just done a quick google search about things to use for removing corrosion from ali. What ever you use, its got to be acidic, not alkaline. So caustic soda if definately a ‘no no’. Will be getting an ultrasonic cleaner at some point. Its good to know what cleaning fluids I can use with it. Have some brick cleaning acid, so may give that a go if the parts are corroded.

[sidevalve5]

An update, the adjustable tapered screw does work very well with Zenith 24T2 carb that has a fixed jet. The Jap 6 in my newly acquired Trusty was obviously running rich. Had to take the head a barrel off as part of the re-commissioning and there was a lot of sooty type deposits. It was not hard baked on carbon, which I would have expected if it was burning oil. I set the fuel/air mixture with a plug chop and after a couple of efforts with doing adjustments, I have the plug with the correct brown coloured deposits on the end. The engine sounded beautiful and pick up from tickover was smooth. But currently only scuffling with 7” diamond feet on 5 legs, with at 2” deep in ground I have already gone over both ways with ducks feet at 3” in clay soil that was padded down well. So did not need much power on the already roughed up ground. Find when I put a SV engine to harder work and if I have the correct brown colour on the plug, I get a bit of a hunting type misfire. A tweak to richen the mixture usually cures it, even though the plug colour changes more to a charcoal shade.

The Zenith carb on the Jap 5 was taken off a Trusty that must have been left outside uncovered for decades. It had thick corrosion deposits inside and out, could clean off what I could and blew everything through with an airline. Have also recently had it ultrasonically cleaned. But the air mixture screw makes no difference to the tickover, unlike to carb on the Jap 6. Where I could adjust both main and idler jets. I think that the blind holes and passageways still have corrosion deposits in them and was thinking of soaking it in something like drain cleaner or caustic soda. Would be interested if anybody has any advice as to what is the best solution.

[sidevalve5]

Many thanks for the replies. My old Trusty Jap 5 has now done its time, the transmission is worn out. Had rebuilt the engine and it was working very well before the transmission system broke. Have a Clifford Mk1a, so am going to put the engine on that and scrap the Trusty. The Jap 6 Trusty has a graunching sound from the very slack primary chain hitting the casing. Had this problem before so at the weekend am going to see if a half link will fit. Put some new clutch springs available at the club shop on my old Trusty, they made a big improvement. So at the weekend, if the Jap 6 clutch shoes have less resistance that the Jap 5 one, will take them off and fit them on the more recent machine. Will be saving the springs anyway, have two Douglas engine Trusty’s awaiting restoration.

The Jap 5 has the adjustable carb needle, so am going to put it on the Jap 6 and see how it goes. Have nothing to loose and can always return it back to the fixed jet. Many thanks for the offer David, but have a spare Zenith carbs with an adjustable needle. When I get round to restoring the Gravely D I might have a go at fitting a modern carb to it. Think the Zenith is too big so such a small slow reving engine. But thats for another day.

[sidevalve5]

There were a couple of errors on the original post. The Villiers engine was a VIIIC and the top ring gap ½” up from the bottom of the cylinder 0.063”, the second ring in the same position 0.054”. Also should have said the Hastings recommended clearance between the axial height of the ring AND THE GROOVE should be between 0.001” – 0.003”. Apologises for any confusion.

Hastings Piston Rings have written their advice to include tuned and high performance engines. Ours are on the very opposite end of the scale, so should think the tolerances can be greater than the advised. But the closer you can get to it, the better the performance will be of any engine.

The post was nearly exclusively about re-ringing, when to do it, how to measure a cylinder bore with just a ring and feeler gauges. Also where to get rings if the original parts are no longer available. After disassembly, obviously other aspects of the engine need to be inspected and work undertaken as required. FYI the Gravely D had very worn guides, so had some made by a mate who has an engineering business. The Villiers had worn main bearing bushes and play on the big end. Enquired at a Villiers specialist engine rebuilder and he wanted a huge amount of money to do it. Managed to get the bushes and big end rollers. A vintage motorcycle racer could do the crank, press in the bushes and ensure everything aligns. What surprised me about that engine was the amount of wear on the rings, bushes and big end rollers. Yet the cylinder bore was OK!

Do not wish to get into a ding dong battle of opinions. Will only reply to a comments if I think it will make a positive contribution.

[sidevalve5]

Dear Andy,

This is going to be my last reply on the subject. I do not wish for the conversation between ourselves to descend in acrimony.

Am glad to say we do have an area where we share common ground. Have too amassed a large collection of horticultural pedestrian machines and mowers. A lot were rescued from redundant market gardens that were one so prevalent around Evesham. Have done some up so they are in good working condition. Am fortunate to have a smallholding where I can use the machines for the purpose they were originally intended. Where I diverge from yourself is that I have repaired/renovated/improved each magneto on the machines myself with a 100% success rate. As I use the machines, I require full power and reliability. The methodology of the work I have done on the magnetos is covered in the original post

An area where we are similar in another aspect is that I too have experience of magneto ignition systems from the 1970’s. Although at that time I was very much into motorcycles, both British and Japanese. Repairing them for myself and friend’s. I read copiously, so I could then understand the various ignition and charging systems on the bikes. Both in theory, their practical operation, how to test and repair them. A multimeter was vital for this. I also was a Grasstrack racer, the bikes were fitted with a variety of mags, including the racing type. The engines ran on methanol at 7500 rpm at a 1:15 compression ratio. A big fat spark was vital. There were four of us in a group who worked on the bikes and went racing together. The best mechanic and tuner was trained as a horticultural service engineer. The shed was at his Dad’s house, who himself used to be a Francis Barnett works rider and was the ‘go to’ man to repair the plethora of Trusty’s that were around the locale at the time. He had a section of the shed to do this and apparently had ‘special tools’ to work on them. We worked on the mags ourselves, I recall just one being sent to a specialist repairer, he charged £70.

Additionally I have a very good mate who runs and electrical auto repair business. They do all sorts of specialist work in that area, other garages send the vehicles they cannot do to him. He has the experience to work on older vehicles too and has recently purchased a couple of British bikes, including a 350cc AJS that is difficult to start. We went to Italy last year as part of a group to watch the MotoGP, it included a trip to the Ducati factory (wow). We discussed at great length magneto ignition, their testing and capacitor improvement. He concurred with everything I said.

I wish I knew then what I know now. The expansion of my knowledge has been greatly accelerated by the world wide web. Where research can be carried out and information obtained. In the case of ignition systems, including magnetos, from highly skilled electronics engineers who have taken a particular interest in the subject. Some of the YouTube videos by service engineers or keen amateurs regarding testing coils on small engines were a bit jazzed up. Many were from Americans who could get a bit excitable when explaining something. But in just about every case, they all did the same thing and tested the HT coils (a lot were the transistorized types) with a multimeter. Am afraid I just cannot believe ALL of them are talking rubbish. Some are clearly professionals and repair small engines as part of their livelihood. I started to look at the videos in earnest when I had a coil pack up on a 4hp Briggs & Stratton engine, confirmed by a multimeter ohms test. The engine had points and I understood the system could be replaced by a transistorized module. It could and the YouTube videos proved invaluable in showing me how to do it. They also confirmed the HT side of a module could be checked with a multimeter, but not the LT circuit. Know several mechanics and they all say they look at YouTube regularly to see how others in their trade solve a problem. Some of the British magneto repair specialists have written extensively in the explanation and advice pages on their websites. These include The Magneto Guys and Brightsparks, particularly the latter, which is where I got a lot of the information that formed part of my original post. I invite you to go to their website https://brightsparkmagnetos.com/ and in particular read what they have to say in the Document Library tab. There is a huge amount there, its very informative and well worth a read. I can also vouch for the improvement in an engine’s hand starting and tickover after fitting an Easycap.

As regards to your comments about some Villiers and Millar mags you have worked on not being able to give a 6mm spark. Without you being able to test the mag adequately, how could you find a fault. Am presuming the air gap between the coil and the rotating armature or flywheel would be correct, the points gap and their contact is good too, the flywheel magnet has not lost some of its power. Then if it sparks at less than 6mm the most likely problem is a slight leakage of voltage from either the HT or LT side, or the condenser. A multimeter used as a resistance tester would allow you to identify the problem and fix it. If the resistance readings are OK, then its almost certainly the condenser. I am fortunate to own an old wind up megga that I got so I could test electrical underfloor heating cables during their installation. So can test a condenser too. If required it would also allow me to test the insulation levels between the various parts of the mag as well. But have never had to do it, have got every mag I’ve worked on to achieve a 6mm spark. Most will not have access to a megga, so after the experience I have had with the fitting a modern capacitor. My recommendation is if the LT and HT resistance figures are good, but the spark is still less than 6mm, replace the condenser with a capacitor.

In reply to your particular question as to why professional magneto repairers use specialist equipment is because they run a commercial business. A good proportion of their jobs are to do with very old, rare magnetos, many with rotating coils that require extensive rebuilding at a very high cost. They rewind coils, carry out remagnetizing, manufacture slip rings and other parts in such a magneto. They need to test the electrical elements as the work proceeds and not at the end of reassembly. But they still use a multimeter, its a vital instrument that ALL electronic engineers use for testing. They even show the instrument being used on their websites. A simple resistance test of a coil of enamelled copper wire does not need specialist equipment, the engineers would use a multimeter. I think you are confusing apples with pears. A Wico Series A, or a Villiers 25c mag is not at all comparable to say one off a WW1 aircraft.

Am sorry, but I fail to understand how you can be so dogmatic and not to look once again at a subject when additional information is provided. Surely one of the advantages of the ‘University of Life’ is that it teaches you to be open to fresh ideas from others. This should include the conception of resistance along the copper wires of a coil, how to test it and interpret the figures obtained. A break, partial or full in the copper wire of a coil, will show up in a resistance test by a multimeter. Likewise if there has been a significant arc and some wires have fused together. You appear to view the multimeter as just a simple volt and continuity tester and not appreciate its function as an accurate ohms tester too. I have countless times changed a long held view when presented with new evidence. You seem keep following the line that magnetos can only be tested by specialists using PROPER instruments and these include something of a likely 1950’s vintage that came from a school lab. Unless it was an oscilloscope, it would rely on an electromagnetic coil operating a mechanical dial. What I do know from such devices is that they would need regular calibrating, so the figures indicated by the dial would be accurate. When was such a calibration last done? Why did the school let the instrument go, was it because it was out of date technology, or inaccurate and needed to be replaced? You have not stated what this PROPER tester actually does? My £8 multimeter is accurate to + or – 1.2% from 0.01 ohm and to many K ohms. How accurate is the PROPER device? Does the person operating it know how to interpret the figures obtained? Is the test a simple ohms and/or a spark test that could be done with a multimeter and an adjustable spark tester by a home mechanic? Has the replacement of the condenser with a capacitor been considered? These questions need to be answered in full for you to even start to suggest a multimeter cannot test a magneto. Am afraid the experience of the University of Life and your 40 years in the industry does not mean that you can make such a definitive statement unless you can back it up with technical evidence. I have produced mine, I invite you to enlighten me with yours. Am respectful of your experience and if you can prove to me from an electrical engineering standpoint that a multimeter cannot test a magneto coil. I will look at the subject with fresh eyes.

The forum readers can make up their own minds to who is correct about the topic of the use of a multimeter in magneto testing by someone with a small degree mechanical skill. I can only reiterate yet again, the whole purpose of my original post was to encourage others to ‘have a go’ at taking apart, cleaning, carefully reassembling and testing a magneto in their own workshop. The mags fitted to horticultural machines and mowers after the 1930’s are not very complex, they are pretty robust, with many parts being readily available too. They are really not difficult to work on, am sure many will be both surprised and very satisfied with a successful repair and/or improvement. If in the very unlikely event of you not managing to get a good spark. You always have the Plan B route of going to a specialist. But “nothing ventured nothing gained”. I wish to now leave the subject and will not be making any more comments in this string. I will however reply to a new post about magnetos and refer the writer to this conversation string, so they too can come to their own informed conclusions over the matter.

Best wishes,

Grahame

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