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Member postings for Ramon Wilson

Here is a list of all the postings Ramon Wilson has made in our forums. Click on a thread name to jump to the thread.

Thread: Anodising
27/03/2010 23:22:58
I am intending to try to anodise some of the parts for the 'Racer' engines currently being built.
I have two articles to turn to, one from the Stictly I/C magazine and one much older by Ian Bradley from ME plus there is some information on the MEN site.
I have no experience of this process other than having read about it so would welcome any thoughts or advice from anyone who has tackled this at home.
I can see that the need for thorough degreasing is paramount but the one thing I really would like to know is - are the parts are  best anodised immediately after machining or can they be left until all parts are ready then the lot is done as a batch?
Many thanks - Ramon
Thread: Anodising
27/03/2010 23:11:10
Double posted - apologies

Edited By Ramon Wilson on 27/03/2010 23:23:33

Thread: Hallam Engine
27/03/2010 23:04:24
Hi Alan,
Thanks for the PM. Thought you and possibly others interested would like to see a some pics of the Ohlson and Rice sparkie I mentioned.
This was recently given to me by the friend I borrowed the Hallam off. Apart from a very rusty steel cylinder outside the internals appear to be okay. The method of construction is quite unusual - the piston has to be rotated through 90 degrees to remove it through the crankcase front as the liner,fins and head are all one piece and are, I am informed, 'spot welded' into the crankcase. The round mark just above the crankcase opening is repeated on the rear and is apparently the 'plug' pressed in after welding to 'finish off'.
There is a heat witness mark clearly visible on the liner inside and I'm told it needs special tooling to replace it if the liner is actually removed.
Unfortunately it is missing it's timing arm and points so something will have to be made if one can't be sourced but the rest of it should rebuild nicely - the cylinder heads were evidently lacquered black and, despite the rust, there is some very slight remains of that to confirm it. It will certainly be nice to try and restore it to running condition again.
My friend was quite positive about 'rebuilding the insides' of the Hallam to see if the running characteristics can be improved but this and this O&R will now have to wait until later in the year though I am trying to get a bit more done on the Racers before the garden takes precedence!
Good to hear you are now getting some results yourself on the Hallam and do keep us posted on your new experiences with the Magnum.
Regards - Ramon


17/03/2010 16:56:37
Well after a bit of a delay caused by unforseen factors I finally managed to get some time on this example today with reasonable results......
But first a day or two back -
Having bolted the original head back in place the lack of compression and sounds of leaking were apparent. A squirt of fuel showed frothing around the head and the plug seating. There are no gaskets fitted to any joints on this engine. The head was held in soft jaws by the cylinder register and a minimum skim taken across the plug seat. The plug, a 'Pacy' was taken apart and the boken insulator repaired with epoxy. (So far no problems with this repair at all). A new copper plug washer was turned and annealed.
The head was then refitted paying real care to the bolting up and the compression improved considerably ( though I still have my doubts over the composite piston's ability to hold compression as well as one machined from one piece).
The cam was set so that with the timing arm in its retarded postion the spark occured just after TDC and a locking arm made from 1/8 brass rod, one end threaded to fit the timing arm and knurled for grip the other. The intake tube and spray bar fitted was the homemade one that had been proven when using glow fuel.
The coil - totally unmarked so an 'unknown quantity' appeared to deliver a good spark from a 6v supply which also showed I guess that the condensor was also functioning correctly. The let down was the petrol - last years lawn mower from the shed kind - spit pop bang - but no run more than two or three seconds and a worn out shoulder however it was felt the parameters were there.
Today however, with new petrol (super unleaded) mixed 4:1 with two stroke oil, another attempt was made. This time the engine showed much more promise and began to fire and run for  a few seconds at a time. These short 'runs' were sufficient to see that even with the much finer control with the home made needle valve it is incredibly easy to flood this engine. The plug was checked - oily - and the gap checked, something over looked in eagerness. The 30! thou gap then was quickly reset to 10, the plug cleaned and instant success - it  fired and ran within an armful of flicks.  By manipulating the timing and resetting the needle the revs improved and the engine settled nicely into a reasonably consistant run.
I have no idea of the revs, perhaps 3000 - 4000ish they certainly appeared much lower than anticipated and are not much more than Alan's engine appears to give. What I was really surprised to find was that the needle in it's optimum position was open just 1-1/4 turns supporting the comment read that "these type of engines (spark) will run on a mere smell of petrol" (It was some 31/2 turns when using glow fuel)
I have had several runs of three - four minutes (have to think of the neighbours) all on a 13 x 5 wooden prop The engine like Alan's is still new inside and needs to bed in as yet but is not tight anywhere. The timing arm is not critical as such, but does need to be in 'just the right place' to give a consistent run and being able to move it whilst running is definitely a requirement.
As with trying it on glow it does get hot and begins to hunt a little before dying off slowly (newness perhaps) then it does not like starting until it cools somewhat, however I might try some smaller props perhaps 12 and 11 x 5's to see if the run smooths out at slightly higher rpm 
I did take some video and yes I have managed to get it into the computer however does this have to go on You Tube for anyone to see it or am I able to use Picasa as I do with still pics ( I've had a good look on Picasa today - it talks of movies and video but simply can't see how to get the file on there for others to see - anyone know how to do this?
Despite some thoughts I have learnt quite a lot by taking an interest in Alan's initial posting - it has brought me into contact with others whose opinions have been taken at face value then acted upon to prove right or wrong. By doing that I now feel much more confident in attepting a 'sparkie' of my own in the near future which I guess is what its all about.
Regards for now - Ramon
Thread: What type of STEEL?
08/03/2010 09:34:54
For the home user steels are usually heat treated in two basic manners - 'through hardening' and 'case hardening'. Keeping it basic then --
In the first, the metal, after heat treatment, is as it says hardened completely through the part. This then requires 'tempering' to reduce any tendency for brittleness and to reduce the hardness to the level required for the application of that part. The kind of steels normally encountered for this are silver steel and gauge plate though you can of course now add EN8 to this
['Silver steel' is not a generic term. It is what it is. Keeping this 'practical', as already said, this comes as a very bright ground finish. It normally comes in 13" lengths (though it is available in longer) and sometimes, though not always, it is marked 'Stubbs' on the end.  Ground mild steel round bar can, to the inexperienced, be visually mistaken for it. The easy test then is as someone has already commented is carrying out a 'spark test' or better - taking a thin slice and quickly heat treating it - the result will quickly indicate which you have]
In the second method the part is encased in a compound which is high in carbon and then heated. The carbon deposits into the surface of the part, the longer it is held (at temperature) in the compound the greater the depth of the 'skin' but this is usually only a few thou. Hence the term 'Case Hardening'. The hardess of the skin is usually left as quenched the core of the part remaining ductile though this can be further heat treated if desired. The steel has to be suitable for this process - the (very) limited amount I have carried out using this method was using EN32b.
There have been several books written on the heat treatment of steels for the home user all of which will give you sufficient detailed information as to what is occuring as you carry out these proccesses as well as how to carry out it out at home
There are of course many other ways of hardening metals but these are really well outside the needs of the home practitioner
Hope this helps- Ramon
07/03/2010 22:14:10
Ray (Macmarch)
I'm afraid I'm not.
I'm at Beccles in Suffolk so Peterborough is a good 200 mile round trip! Usually come up once a year though.
06/03/2010 21:07:17
DC, Macmarch, Chris and particularly James.
I hang my head in shame
For the best part of thirty years I have, on more occasions than enough, made parts from EN8 - work and home - thinking that this was a 'tough' steel at the low carbon end. These were always left in their soft state and until David's post I  was truly unaware that this was a 'through hardening' steel. Despite simply loads of heat treatment work with many other types of steels I would never even considered it but sure enough there it is in MacCready's handbook. Oh dear!
Well guys I can only apologise and appeal in mitigation that I was trying to help someone based on what I believed to be factual.
It reinforces that quotation that you really can learn something every day and yesterday I did.
Redfacedly yours - Ramon
(Sorry for the late response but I was out until late yesterday and only just in from a trip to Peterborough today).
05/03/2010 13:00:53
Er I think perhaps you have missed the point - I don't actually say EN8 to be a 'mild steel'  but a 'low carbon steel' which in my experience it is, certainly tougher than mild steel I agree and ideal for the parts you describe.
This subject, we all know, is immense and the idea taken up by DC is perfect timing.
05/03/2010 12:12:06
Yes, totally agree with KWIL James, I just didn't want to add too much 'extra' at once. Taking cuts does work reasonably well but it can be a pain as it doesn't always aleviate the stress equally. If theres nothing else though it's the best method of dealing with the problem.
Stress relieving however if you are in a position to carry it out is much the better option on BMS. As an addition to KWILs good advice if you can get hold of some fine fire ash bury the (red) hot metal into it it will cool a lot slower than in air
05/03/2010 11:27:56
James, your query indicates that of a beginner and as Tony says a tall order.
I can't improve on Tony's excellent overall description but I feel you may need a little more practical help.
As said all of these materials come in many forms and grades within their respective 'subtitles' but for the model engineer the knowledge of a few basics will help.
Cast iron is a relatively easy material to machine using conventional HSS tooling and or carbides. It is not normal to use coolant or cutting fluid when machining (Tapping excepted) Castings all have a skin which can be, though not always, much tougher than the material beneath. The hard spots mentioned can be a problem but reducing speed right down and or using carbide normally solves the problem. Continuous cast bar is 'lovely' stuff to machine, very homogenous and consistent quality. Once you have seen and machined a piece of cast iron you will have no difficulty in recognising it from then on !
Steels likely to be encountered at least to begin with are Mild steel either 'Bright' or 'Black'.
 Bright is cold drawn and has on flat bar - at first look - a nice smooth flat surface. This can be misleading when you need something actually 'flat'. It's big draw back from a machining point however is that because of it's method of production it has high stresses 'locked' within itself and when a cut is taken these can release to a greater or lesser degree to produce some remarkable distortion. This can catch the unwary - it is best if possible to relieve the stresses by machining small amounts of each side gradually. This problem is not normally experience by turning round bar.
'Black' mild steel on the other hand is 'hot rolled', has varying surface 'qualities' and  is not always square on its edges or very round but exhibits little, if any, movement after machining.
Both these materials are ideal for home machining and uses include linkages, con -rods structural parts etc. Preferably use coolant but can be machined dry but cutters will wear quickly
Leaded 'freecutting' mild steels EN1a etc are excellent to machine, a little softer than the above but much easier to produce a really good surface finish, lathe or mill. preferably coolant again.
The lower carbon steels likely to be encountered for instance EN3b EN8 are slightly tougher and used for similar parts likely to be subject to a little more stress.
Higher carbon steels as said can be heat treated to a hard enough state to use as a cutting tool or a surface much more resistant to wear than in it;s soft state. The two most likely to be encountered are Silver Steel - available in  vast range of diameters -metric and imperial - and is easilly recognised by it's ground bright silver finish. Gauge plate again in a vast range comes flat  normally pre ground  all round but some times has cut edges on the wider flats. Despite iits appearance it is not always truly square
Both are tougher  to machine than mild steels. Use coolant or cutting fluid
Stainless I have less experience with but some are magnetic, not true stainless but considered 'rustless steel' Some stainless is notorious for work-hardening. It is most important to keep the tool sharp and cutting.
High Speed Steel is what you will use as a cutting tool. It is not normally available to the home user in its soft state and in most instances though not all comes ground either in square, rectangular or round form. It's only 'machinable' by grinding and has the property of retaining its edge under higher heat build up than carbon tool steels.
'Brasses or Bronzes' of which 'gunmetal' is one covers an enomous range. Normally used for bearings or fittings (because of it's propensity to resist corrosion) it is also used for castings of lighter stress components as well as major items such as cylinders. Machining again is relatively easy but requires absolutely sharp tools. A tool previously used on steel - if only once -will tend to 'push' the material as opposed to a clean cut.
Drillng of bronzes can be difficult because of work hardening. Again sharp tooling and small cuts - drilling in steps - will prevent workhardening.
As Tony says the subject is considerable, this scratches the surface and I'm ceratin their will be more o come for you - However I hope this goes a small way to expand that already posted.
The one factor to be borne in mind is that all these different materials have differing cutting speeds - that is the rate they rotate for their diameter on the lathe or the rate of the cutter on the mill  - a subject in itself and catered for elsewhere on here as I recall
Kind Regards - Ramon
So far no one has commented on the costs involved. How long is a piece of string I guess.  Tony sums it up well in that you need to know what you have. Buying it should guarantee that but not from a 'car boot' sale for instance. Then you do need that experience to be able to make a judgement.
The best of luck in your endeavours James

Edited By Ramon Wilson on 05/03/2010 11:34:05

Edited By Ramon Wilson on 05/03/2010 11:40:53

Thread: Hallam Engine
04/03/2010 23:28:56
Hi Alan,
That's interesting you are sure it wasn't oscillating. I've seen it before on small engines diesels in particular when it can sound quite 'rough' but never as smooth and as ready to run as consistently in the state as this one was today! so I guess we need to keep looking then
I'm still convinced this is a fuel/air problem possibly coupled with internal distribution. Your description was the problem I found - just a mere crack of the needle was sufficient to bring about a flooded state. The system made is much better at controling the fuel and it will run over a good turn or more. Screwing it in gradually leans it out, the rpm increasing and the engine note becoming smoother. At this stage though cooling, or rather lack of, becomes a problem, those fins are so marginal, there isn't really much material (even on that original head) to dissipate the heat and the engine soon loses its seal until it cools again. It isn't labouring at all but it definitely prefers a richer mixture to aid cooling.  That is not to say it's being leaned out to such an extent as to cause overheating - like yours it's new - virtually unrun so that is not an option as yet. The newness is born out by the crankpin. It is in very slightly 'on the huh' sideways (looking down on it at TDC). This has caused the bronze big end bearing to deposit on the pin - something there was no evidence of when initially stripped down but this doesn't appear to be having any apparent effect on the running as yet. Despite this newness the engine flips over very easilly - no sign of any tightness at all at any point.
Having now established that it does indeed run I shall now get on to the spark side. I have read up as much as I can from what I have been able to obtain so far on engines of the period and most describe the cam as fitted as the norm. But like you I can't 'see' at the moment how that short closed period allows sufficient time for the coil to work. It will probably be next week before I will be able to get back onto it. I just hope the coil and condenser I have are serviceable. I certainly don't want to think about electronic systems at this stage though there's no doubt they seem to be much more positive and reliable. 
Glow plugs can be 1.5v or 2v. A 1.5v can easily burn out on a freshly charged 2v battery.
and the 2v don't work too well with the 1.2 v rechargeable type self contained glow plug 'starters' if the engine is a bit of a recalcitrant one (This is all hand starting of course)
A rubber sheathed wood 'chicken stick' isn't a bad idea, I did get a few raps on the back of the fingers today - occupational hazard? - but I really don't like those thick rubber finger protectors as you lose all feel of the engine. A good stout leather gardening glove is what I use - doesn't stop the occasional whack but the fingers are still all here!
The video transpires to be slightly disappointing in that it doesn't run for long enough - a non modelling friend was taking it for me and the camera only has a couple of mins recording time. The big problem though is that so far I have been unable to transfer it such that I can post it. I will work on this though and see if I can get some better coverage and with luck actually get it on here.
04/03/2010 17:27:45
Hi again
These pics are taken retrospectively - it appears I deleted the ones previously taken when running the engine!
So, for those who have an interest -  (grannies of course - the usual).

Shows the increase on shaft dia, collet and prop driver. The cam is the original.
Just about shows here no piston port and the long (and large) transfer passage
Checking the timing
The two heads - the depth is the same but the original is sligthly more concave.
The parts for the intake tube and spraybar. The needle is .048 piano wire the needle thread 8BA (mild steel studding drilled through) The cross hole and the hole the needle seals is .037 dia
Unit assembled - Knurled part is a locking nut
These last two were taken in an attempt to try to capture the difference in oscillating and running (in case the video doesn't materialise  - I haven't used that before) They don't really capture it but the first is when the oscillation is occuring the second after it has cleared  itself. The only indication is the prop and I accept it's not particularly convincing . I will now try to get that video sorted then!


04/03/2010 16:58:05
If you are not able to follow the same path regarding making parts then once I have (or not as the case maybe) got it running as intended then you are more than welcome to these bits.
And so now to discover the delights of 'spark manufacture'
Regards for now - Ramon
 PS I have taken some pics as well as some 'video' on the still camera.
I'll try to get them posted later.
04/03/2010 16:53:29
Hi again,
Alan, further to your oil bound frustration which, I am now pleased to be able to state I can  sympathise with personally, I think I may have found the reason for your engines problems - and almost certainly if the characteristics experienced so far with this example are anything to go by.
I now have this one running successfully albeit not on spark ignition - that is the next stage - but I thought you and others may be interested in progress so far.
In order to ascertain whether this engine would run at all I decided to take onboard the advice of Hugh, who is, after all, well experienced in running petrol engines and does, to be fair, actually practices what he preaches but first I took another really good look at the various engine parts and it's make up beginning with the carb.
The needle has a (relatively) coarse thread and taper and it was felt that this is probably the root cause of the 'rich' fuel situation which, for this example certainly, has proved to be.
The piston does not have a transfer port in the skirt so could be fitted the wrong way and it would still run though probably nowhere like it should. The transfer port is cast into the crankcase and connects directly with the main cavity. However this is only a possibility and not likely to be the cause
The timing was checked with a timing wheel and shows the exhaust opening for 100degrees the transfer 78 degreesand an inlet period of 76 degrees.
Before any running could take place a simple cylinder head to take a glow plug was made the internal shape simulating the original with no attempt to reduce compression. Indeed I would think given the quick method of producing the shape it is possibly very slightly higher.
A propellor driver and brass collet were made but this would not grip as it had nothing to push back against on the 5/16 dia parallel shaft. The front housing was bored out to take a larger phos bronze sleeve and the crankshaft diameter increased with a high carbon steel sleeve loctited on and then turned between centres to a running fit.
Using standard 80:20 Methanol/Oil glow fuel the first attempts at starting showed a total impossiblity to control the fuel flow from the crude needle arrangement the engine simply flooding and refusing to start.
A simple venturi was then turned up from ali with an increase in the bore size to 6 mm and a slight 8 degree taper in the inlet end. A basic 3mm dia spraybar was made with a much finer thread and needle taper. Whilst the bore was increased the choke area is possibly slightly smaller than the original (Visual comparison)
At this stage these are the only alterations to the engine - one a practical need
(crankshaft) the other an improvement on fuel supply. I really do not think the original 'carb' is up to the task - certainly for glow and which will probably be the same for  petrol.
The compression with the new head is good but not excessive and the piston seal likewise. After quite some flicking (I have never used a starter) and some finger biting 'pops' the engine began to fire intermittently before running - I believe - in an identical fashion to yours. (It certainly sounded the same) Thing was it took a few seconds for the penny to drop. It wasn't actually running! but merely oscillating - firing alternately back and forth quite happilly.  Gradually closing the needle (about 31/2 turns open) a few degrees at a time  the engine suddenly gave a couple of burps and burst forth into a free and easy run albeit backwards as side ports will do. The finning on this engine is 'marginal' to say the least and with that solid head it was difficult to keep cool but I have had several runs today like this oscillating at first followed by running 'properly' in either direction two or three minutes at a time. Like all lapped piston glow engines though virtually impossible to hot start so plenty of tea breaks!
My old analogue tacho, languishing in the model box unused for several years is typically now not working but I would hazard a guess about 4000 or so on a 13 x 5 Zinger wood prop. I hope for a loan of one so more on this later.
Now whether this is happening to yours given the need for a spark at the top of each stroke I don't know but the similarity in sound  as well as visual appearance to your video is striking. I'm sure you realise Alan but I'm not saying this is what is happening to yours merely my observations on this one but it's probably worth another look. Its easy enough to spot though by the difference in draught from the propellor - virtually none whilst oscillating but a good breeze - forward or back otherwise!
Based on todays experiences then my opinion at this stage is that the fuel system delivery is definitely critical to this engines make up. The second half of Hugh's statement 'if it will run on glow it will run on petrol' is yet to be proved but so far, with the first half out of the way, I feel I'm on the right track.
If you are not able to follow the same path regarding making parts then once I have (or not as the case maybe) got it running as intended then you are more than welcome to these bits.
28/02/2010 17:52:22
Having taken another look Martin that's not an unreasonable question as there doesn't appear to be a breather vent visible anywhere but that may be well hidden under the cap. Whether that would have the effect of the apparent restriction on running remains to be seen, I would have thought that if the tank were 'sealed'  the engine would eventually stop through lack of suction. A very small vent eg a crack around the inlet pipe etc may allow some equalisation but might possibly have the effect of causing the engine to run lean as the pressure inside was reduced and richening up as it it equalised however whether that would cause the engine to stop as Alan describes when he moves the fuel needle either way seems to point in another direction.
I notice Alan your engine has no webs on the front housing , probably machined off for easier movement on the timing arm perhaps? or just a different casting.
Regards - Ramon
28/02/2010 15:52:11
Hi Chris,  Yes it does!
A fair comment, based on your personal experience - and nothing a better indicator for making ones own mind up - a factor I totally agree with.
It may be that SAE 70 proves to be too thick but at this stage I will take on board what my friends are saying as well as taking note of other opinions expressed. Like so much in life one should listen to all carefully before making a judgement.
As I stated quite early on this thread I do not have any personal experience with spark ignition motors but that my intention was to build one. That hasn't changed and taking an interest in Alans request has spurred me on to do so even more.
I guess if I am guilty of anything it's taking an interest, with my own interest in mind too, in someones problems and trying to help based on the info already possessed on small IC motors as well as, at this stage, as that of others whose experience I know of and value. Turning to such others at  times for info that one is ready to accept but perhaps others won't is not something that can be foreseen and in all probability you may have similar aquaintances possibly in other fields that you might do likewise.
As you say 'it does take all sorts'
I intend to be back with a running example of this old engine too so please be assured that if the oil proves too thick or too much or it doesnt do or live up to what I have been told then I will be the first to admit it - redface or not  
At this moment though I would just like to see Alan improve the running of his to his satisfaction and that I at least can get this one to fire.
Regards  - Ramon

Edited By Ramon Wilson on 28/02/2010 15:53:32

27/02/2010 21:55:55
Yes Alan, quite happy with the direction - short side to the transfer.
As above  - found the pics okay - thanks.
I believe 1/4 x 32 plugs are now readily available - I'm sure I saw that Just Engines sell them. Whether you can get 3/8 though is another matter but an adaptor could be made. It would be nice to get an original unmachined head for this - it's not very good and is poor by the rest of the engine.
Bye for now
27/02/2010 21:47:42
Hi again Alan,
I'm afraid that beyond the most basic facts the mysteries of the ignition system mechanics are yet to be discovered.
However the cam on this appears to be the same as yours closing for a very short period relative to the lift. (This flat also appears filed on)
As you see it the points have just rotated around the engine, currently they are loose and will rotate to the same top position as yours. As it stands the position can be locked with a  screw but a short threaded bar knurled on the end would help move it while running and allow locking which is something I'm certain I have seen on other engines elsewhere.
BTW as a matter of interest is yours assembled with round head 1/8 whitworth screws?
(The four cylinder head bolts on this go in no more than three or four threads!)
Your photos appear to show what Hugh described as the original tank - made from a casting. This one has just a piece of tube with an end turned from flat plate let in.
27/02/2010 21:18:10
Hi Alan,
I have stripped this engine down this afternoon and feel fairly certain this one is home built. I dont know what your piston is like but this has a shallow slope on the exhaust side with a much shorter one on the transfer side. This one is a composite with an ali top riveted to an ali insert for the gudgeon pin clamping a cast skirt.
My intention was not to insult you with the suggestion of wrong assembly merely  a suggestion on something else to check.
The reason I think this one is home built is that virtually all the flat faces appear to be filed including the piston top.
The crankshaft is made of three parts the pin and shaft silver soldered in place.
The piston seal is not particularly good but I will carry out Hughs recommendations and see where they lead to. I will have to get a new plug (or make one) as this one is broken.
Regards for now - I'll keep you posted on developments.
Chris - I'm not quoting from 'hearsay' per se. The two people I contacted are well known for their knowledge of vintage model engines. One earns a living repairing, making parts and building replicas the other has  a lot of experience with using them in tethered cars and hydoplanes. Their advice is possibly not perfect in some quarters but I've known one a long time and of  the others experience for about the same.
However, at the risk of possibly being castigated for quoting from such, perhaps you will be reassured by the fact that Westbury who, in his book Model Petrol Engines (of which I have literally just obtained a copy this evening) states and I do quote (p159)
"A 250cc motor cycle may run quite satisfactorily on a mixture of 1 part oil to 16 parts petrol while a 5cc engine may require 1 part oil to four parts petrol" unquote .
The 'technical' reasons why a small two stroke petrol engine requires this amount is not something I know the answer too as yet but standard glo fuel is either 75:25 methanol/oil or 80/20 depending on the engine (I had better add - of the ones I'm used too!)
He goes on to say that the most suitable proportions are found by trial and error and represent a compromise between under oiling and over oiling.
It would appear that four to one is a probably a good starting point then.
Kind regards - Ramon
27/02/2010 15:57:40
Alan I forgot something.
Hughs advice to me was to fit the engine with a glowplug -an adaptor will need to be made - and try running it on methanol (and oil - castor that is or commercial glow fuel) first. Not for long just to establish its abilty to run - you should achieve a more flexible run against needle valve settings.
The timing cam has to be set in relation to the piston and the timing bracket should be capable of movement and locking whilst running. He recommends a retarded spark for starting - just ATDC
There is also the fact that if yours was home made the porting/timing events may be restricting things.
Just thought - you do have the piston in the right way? Some side port pistons have a step on the top to one side - this has to go on the transfer side of the bore.
Now I really am off to the workshop!
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