CTS - thank you for the feedback.

Retarding and advancing the timing. I'm not currently able to work out what position the magneto needs to be in to be discharging at approximately the right time. None of the instructions I have been able to find match the hardware I have so I'm basically lost still on getting it all in sync. Only one timing mark on the magneto means I don't even know where to start with aligning it.

Flywheel. The marks don't show up well in the photo, but they are clear enough in person. As mentioned the pointer on the pony motor is there and I can line the "MAG" mark up on that, but then I'm still lost on how to align the magneto.

EX CL is "exhaust valve closed" seems reasonable.

Regarding setting the magneto - this is the problem. I don't have instruction that match the hardware and the magneto itself doesn't have clear timing marks to align, so I'm lost. I'll take some photos today and post them.

Regarding feeding a wire into the cylinder to find the piston top, I've dibbled around in there on both sides and can only find what feels like a valve. Not knowing the internals I am quite cautious about sticking things in it and rotation the flywheel.

Yes the electric starter is a nice to have. Given I'm doing this on my own thought it makes it a lot easier to test the motor. If I had someone else to wind the rope up and pull it when I needed then that would be ideal. It just slows everything down.

Yes using another motor to turn the flywheel is an option, but I'd have to buy a stationary petrol motor for that. If that's the case I figure I may as well just spend the money on getting the starter motor fixed.

the mag could have been rebuilt at some stage with parts that fitted and not necessarily had the correct markings on them. if you could get drawings with the correct marks you could mark them your self.

its also possible the key ways in the gear or the shaft have been re cut to repair damage etc. the devcon and loctite epoxies we can use today didnt exist back then.

Trainkidz - I hadn't considered that, you may well be right.  The problem is that I have looked at the illustrations in the book and the descriptions and none of it matches my magneto.  When I position the timing mark on the coupling (which is standard to the illustrations) as instructed, then the rotor is in an entirely different position to what the illustrations show it should be and the breaker points are not just about to open.

I haven't removed the rotor, so it's just where it was when I pulled the magneto off, so the coupling and the rotor are still at the same angle to each other.

In theory, there should only be two possible positions for the magneto - rotate the coupling 180 degrees for the second position.  I've tried both and no luck.  When I try to align the breaker points "just opening" with No.1 piston in compression, top dead centre, then the magneto coupling is always 90 degrees out of phase so can't be installed.

At this point I'm just tied in knots with it.  It was working (historically) with this set up, but it won't for me now.  I really don't know where to go next, other than arranging a rebuild of the starter so that I can more easily test if the spark is synced with the compression.  That's about all I can think of for now.

Hi, LangdonStevenson.
If my memory serves me rightly (It sometimes surprises the daylights outa my by 'ackshully' doing that.), you will need a wire with a slow curve in it to check the movement of the piston due to the location of the 'sparkly' plug. It may require some experimentation to discover the right rate of curve.

I think I would check that first and compare it with the timing mark on the flywheel to see if they verify each other - - - or not. The top of the exhaust stroke will have the timing mark in exactly the same place as the compression stroke. You cain't see the valves to see fi the exhaust is open but holding your thumb or finger over the 'sparkly' plug hole should give you a clue about which stroke you're on.

Azfer your magneto timing issue, I'm a homeless Eskimo - I haven't igloo. But what else would you expect from a 'pore,dumm bulldozer op'rator'????

Just my 0.02.

I would at this point forget all about any amrkings, you need to ascertain by using your thumb over the spark plug hole when the piston on No 1 is on compression stroke, use a piece of wire or ahatever to find the piston at top of stroke and set magneto to just opened points.

Someone may have put things altogether arse about, so the marks are useless, Ii have a THIRTY that the flywheel is on a hole out, so the marks on it are useless.

Wombat

Deas - Ok, I'll try fishing around with a curved wire next time I'm up there.  I appreciate the suggestion.  I *think* that putting a finger over the stopcock to detect the compression stroke and estimate TDC on cylinder 1 corresponded with the MAG mark, but I can't remember now.  Dibbling with a wire will clear that up.

Wombat - I really can't argue with you on that.  The markings don't seem to be helping.  So the wire trick and *actually* establishing TDC on cylinder 1 seems like the way to go.  Thank you for the input.

Find the make and model # of the magneto - Post it here with pictures if possible.
Without removing the rotor, how are you assured the points are clean and functioning? Is the rotor and cap, clean, no cracks, no "tracking". Many things going on in a magneto at the same time to produce a spark - and do not forget the condensor, coil - any one component will have an impact on performance.

Does the magneto produce "FIRE", not a weak yellow spark but a bright blue one that is consistent? (no use fighting a process of timing if the magneto is not producing fire)

Do you have a "shop" that specializes in magneto service/repair available?

Trainzkid88 - suggestion of someone cutting new keyways in the magneto would be extremely uncommon - that would take expert in magneto repair process with machine shop knowledge, something that in most cases would never be attempted.

As a thought - not all magneto's are 1-1 - in other words they may be geared. You may be able to turn the drive "dogs" multiple times for the rotor to line up with the output terminals on the cap? Something that you need to check.

You have had the magneto off, did not mark the locations so at this point you have to start at the beginning, Irregardless of any marks -

Have you "worked" on the engine side of the Magneto Coupling? If that was taken apart and not alighned properly, your timing will be off accordingly.

Ensure #1 is on TDC Compression Stroke -
Ensure Magneto is timed to fire as soon as the points open and the rotor is directed to the #1 terminal.

When you have a "hot" magneto properly timed - your next issue will be fuel in the correct mixture - This will depend upon availability to the the carburetor float bowl and then the carburetor jets and adjustments being correctly set. Ensure you have a full flow of "CLEAN" fuel at the carburetor! You will be surprised how much fuel these engines require at the carburetor!

AGAIN - back to the basics - FIRE - FUEL - AIR and I would work in that order! It is easy to pull a spark plug and use an pump oil can to shoot a squirt of fuel into the cylinder to find it it will "pop". I always liked to add a bit of motor oil to the gasoline, assured a bit of rise in weak compression and also lubed the cylinder.

CTS

Spin the mag in a vice or such and check for spark at the points, clean if necessary; Have the pulley with the timing mark lined up @ 12 O'clock if the metal pointer is missing; slap that mag back on, as you only have 2 grooves. Pull a spark plug and spin the motor to make sure you have decent spark, add a thimble full of gas in the spark plug hole and re-install the plug. If luck has it, you will get it to cough for you. I am NOT a mechanic (ask anyone), the owners manual says how to time the mag, and it makes little sense to me. I went by my own trial and error method, and each time on all of my 318 pony motors, they fired off. Perhaps pure luck? Some encouragement here, YOU CAN DO IT. JM

I will ECHO JM's last 4 words --- YOU CAN DO IT!
Sometimes we get so involved in something, we fail to notice the obvious. YES - FROM EXPERIENCE - ME! Take a breather, then step by step, it will come together.

When you do put the Magneto in a vise and have wires running to a pair of spark plugs or just so they will ground producing a spark - please wear gloves when turning the mag if you do so bare handed, When the impluse kicks, it can bite. Often a small bar or wrench helps but be mindful of spippage and ensure no one is in the line of fire it the impluse kicks the tool out of the "dogs".

Keep us posted, many of us are waiting to hear that Starting Engine BARK!
CTS

CTS - Here's a photo of the ID plate on the magneto:

 

Yes the magneto produced a decent blue spark when I tested it last trip.  That's why I decided not to strip the magneto down any more than just pulling the cap off on the previous visit. "if it ain't broke...".

I'm sure I could find a shop to service the magneto here in Sydney if need be, but for now I don't think it's necessary.

Regarding gearing of the magneto, from memory it takes two full turns of the coupling to get one full turn of the rotor, which would give two spark outputs, one to each of the two terminals on the magneto.

No I didn't disassemble anything on the magneto other than removing the front cover to clean up the contacts.  I didn't even need to pull it off the motor, but didn't realise that at the time, that's my mistake.

Regarding fuel - I pulled the top off the float bowl and that's all looking good.  The bowl is full of clean fuel, the float moves freely and allows more fuel in as the float drops, so I'm confident that's working.  I don't know if the jets are in good shape of not.  That's the next thing I have to learn about and work out how to service.  I am getting fuel down to the No.1 cylinder though (but not No.2) which is encouraging.  And I even did get a "pop" out of No.1 at one point while testing.  So that's positive.

Thank you for the encouragement.  I will get there I expect, it's just going to be a slow process given the difficulty of getting to the dozer and the limits of time and my experience/knowledge.