Case 442 (little guy) ignition question

So my 7 year old was driving the 442 and it was running fine and it stalled like it ran out of gas. I just filled it up like I always do and here is the problem. It now will not run and it seems to be a spark issue. I give it a little shot of ether in the carb and no life, just cranks. Take the plug out and I have compression, take the air filter off and I have vacuum. Look at the plug and I see a spark. An old timer once told me spark in open air is very different than spark under compression. You can have a weak spark that will not go in the cylinder. I will say that I took the points cover off and I do see the spark jump the points quite a bit. I am quite perplexed on where to start. Thank you everyone.
 
I have had Kohler and Briggs engines do this to me in the past and if all else fails put in a new flywheel key as the old one could be tweaked even a half of a millimeter throwing off the timing.
 
Hi, I run a 69-442 PK almost daily. but that doesn't help you, huh !! Anyway I think T Whalen has a good point. timing. Can you match the 'air thrust' out of plug hole. (compression) with the spark caused by the opening of the points. Right when it sparks, should be top-dead-center of the piston. (close) Or check timing by the book.
 
(reply to post at 17:41:37 07/15/14)

If the spark is not bright blue and will not jump a 3/8 gap I would suspect a coil or condenser issue. The timing on that engine should not be dependant on flywheel position as it has points that run off a points lobe on the cam. Also is the cranking voltage staying up while you crank it, if the voltage to the points is low weak spark will result.

mEl
 
On the timing issue, help me think this through. I did the ether, my way of checking fuel, since anything will try to run on that stuff, and there is no sign of life, I would think there would be enough residual ether to at least give me a back fire. I also put a little gas down the hole, also leading me to think if I have fuel, it is not being lit. My old timer friend had this Frankenstein spark plug with a huge gap which he said made sure the spark was strong enough to work under compression. So far the condenser sounds like the cheapest and easiest hunt and peck fix. Any other things I am not thinking of? And thank you everyone. This is why I love this board.
 
The points setting is the only way to vary it's timing as the pushrod runs off a special lobe on the cam.

Back in the day of points style ignitions on multi cylinder snowmobile engines we would use a dial indicator with a special adapter in the spark plug hole to set points opening to a specified amount of thousanths BTDC. On multi cylinder engines the other set of points gap was tweaked to synchronize the timing

If you have excessive sparking across the points as they open I would suspect it as it's job is to absorb the spike of voltage at points opening and then release it back into the coil to intensify the spark, this can be observed on a oscilloscope as a wavy declining of the spark waveform. It should keep sparking at the points to a minimun and a well matched condenser will minimise pitting of the point surface.

Keep us posted, It also could be a coil issue so good luck sorting it out. I assume you have installed a new plug as a fouled plug will often fire the gap in open air but fire down the insulator under compression.
 
Thank you so much. Today is the basic tune up. Points condenser plug. I have never had one stall from running like this. Usually there is a period of hard starting or poor running first. It is unusual to me.
 
I feel like it is a timing problem, my Dad had that with his 530, many moons ago. One other thing, I understand that you had just filled up, so I would think that a bad batch of fuel could also be the problem. I am just saying.
 

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