Keep at it and don't be afraid to experiment a bit. I once had a D2 that I'd bought for parts and that's a whole 'nuther story but after I took it apart and got tired of admiring the bits and pieces I decided to resurrect it. After scrounging the parts I'd taken off it to repair the other D2 I had, I put it back together again. Problem was the pony wouldn't start so. . . .therein lies the story. Without any sort of manual, I pulled the mag and started working on that. No spark. . period.

Being the stubborn old bastid I am I figured that that engine once upon a time ran and it would run again! Bear in mind, no manual and this was before I found this board so. .

I tore that mag down and started rebuilding it. FINALLY I got spark. .actually I got a shock when I spun it with a drill motor. YAHOO. . .it's gonna work! Then it was time to put it back on the engine. Nope, no joy. .it still wouldn't run! That's when I started messing with the timing, making notes as to timing marks on the gears, swapping plug wires each time I'd pull that durned rope.

That was when I found that the marks on the gears were off by one tooth! My joy at hearing it bark just intensified my happiness so I took it off, moved it by one tooth and awaaay it went, cackling away like had just pulled the best joke it had ever seen.

I realize Cat probably has one of the best Q/C setups, but I'll swear that the marks on one of the gears were off by one tooth to this day! That's why I said to not be afraid of experimentation. .If I'd stayed with matching the marks, I'd still be pulling that durned rope!

Once it pops. .or jerks the rope out of your hand:eek: you're getting close. Don't quit now:D

Thanks guys for the images. D4 is 5 hrs away in the bush , so will pack a telescopic mirror and go look for those. My dash is so integral ( see my pull start wheel image above ) I will have to have a 'sneaky' look.

I am worried that I am feeling confident it will run now. Never go with expectations...... I will report back in a week.

Cheers David

A person can retard the spark or advance the spark by changing the mag point gap. A wide gap would be early timing and a narrow gap would be late timing. There is not much room for the gap to be changed on the magneto. 45 years ago I used to race a motorcycle that was a two cylinder with dual points located on the same point mounting plate. After setting the points to perfection, then I would time one cylinder by advancing or retarding the point mounting plate to get it's best operating position. To time the second cylinder, I would do it by changing the point gap. I would run only with the first cylinder until it was timed right and then I would run only with the second cylinder and timing it by changing the point gap. If you got your pony motor magneto point gap off just enough, it would behave as though your mag was one tooth off correct timing.

I just rebuilt my pony motor with all new rings, turned the crank down 10/10 on mains and rods. I didnt have any gear marks due to a fairly rusted cam gear. Im not sure if all magnetos are the same but mine has two adjustments. One is for dwell (points ga), the other is for timing. Magnetos bolt on directly to the motor so they all should have an internal way of adjusting the timing. Adjusting the timing to one extreme can make it so the motor runs a tooth off.

Setting Timing without any marks:

First find top dead center. This is easy to do. Top dead center will have the crank keyway pointing directly at the 3:00 position. From here the right side of the motor valves need to be closed. so the cam needs to be inbetween the intake and exhaust cam lobes on the short side. Short side means that when you look at the cam lobes you will notice the intake and exhaust lobe centers are closer together on one side of the circle than the other. If you installed the cam correctly when you turn the motor slightly in either direction from top dead center either the intake or exhaust vales will just start to open depending on which way you turn the motor over. Intake valves are the valves closest to the balancer. The exhaust valves are the two closest to the cam gear side. From the top dead center turn the motor over one full turn and position distributor so that the points are just about to close and then install.

i replaced the plug leads on our d4. you would think left side output would be for left side cylinder that would be logical but alas no the plug wires go into opposite ports on the rotor cover.

i learned the hard way with experience and much swearing from both dad and i when after 3/4hr dad suggested swap the leads over and it started immediately.
the way i had it the ignition was 180 deg out of time.

also you have to use metal crimp and solder on lead ends with proper copper wire leads. modern silicone suppression cable doesn't work either

i bought good quality ngk plug ends from the motorcycle shop (they also have the correct cable) that are nicely insulated and but they wont work the resistance is too high, put metal ends on no problems just be careful when its running uninsulated ends love to zap unsuspecting fingers as dad has found out more than once to his pain and my glee.

"SSsssteamer" wrote:

Go easy on the ether for the pony motor. I learned the hard way. On my D8 14A, I was in a hurry to start it and I gave the pony motor a sniff of ether. When I hit the starter button, the pony motor kicked backwards and it blew the starting bendix of the electric starter to pieces. Not counting down time, that was an expensive day for me at the NC Machinery parts counter. If I have to, for the pony motor, I will use WD 40 or a squirt of gasoline to start up the pony motor. I save the ether for the diesel engine.

. Wondering if it is getting fuel? This is a dangerous procedure and should only be done in a well vented area with NO ignition source. After reworking a carburetor, I fill the fuel bowl. The I blow high pressure air down the Venturi. If it is assembled properly, you should see the atomized fuel spray out the bottom.