VH4D Update

I have to be close? Knowing I won"t be in town the next week or so I left work a little early to play with the vh4d again. So below is what I have confirmed,

1. I have strong spark.
2. On the upstroke of # 1 cyl 12:00 is about 3/4 of the way to TDC , if I continue to hand crank the flywheel until I hear a snap at the mag I"m at 5 :00
3. I attempted to hand prime the fuel pump with no luck at one time I had fuel in the carb from the pump but for some reason it"s not going in so I will continue to work on that. I thought maybe turning the engine over and spraying starter fluid at the same time it would start ? I took the carb bowl screw off and typically gas would drip out but nothing?
4. Mag is timed per the book with the X showing thru the site screw.

So I have compression, spark, gas I hope, it should go however the timing is confusing me. I"m getting a lot of good advice but a lot of different direction, I appreciate all the advice right or wrong it"s getting me more up to speed on the engine and how it functions. As you can tell I don"t have experience with engines on this level and a learning experience it has been, I"m just ready for class to be over and this thing to start already, any how thanks to all for the advice talk soon. Scott
 
I wonder if your engine could be one of those little oddfire V4 engines. I worked on and timed one of those a couple years ago.
A dead giveaway of an oddfire V4 is the location of the rotor in the mag. If the rotor goes directly on the mag rotor shaft instead of having the little gear set that reduces rotor speed to 1/2 of mag speed, it is an odd fire engine.
another clue is the 4 lobe point cam.
Look if the mag cap is inline with the mag main shaft instead of above it like in the even fire V4.
IIRC(it,s been 2 years) the oddfire engine fires the right pair of cylinders in the first 180 degrees, then turns 270 degrees before firing the other bank in the next 180 degrees.
The mag runs at crankshaft speed, so it fires 8 times during 2 full crankshaft revolutions. 4 of the 8 sparks are "wasted" on the exhaust strokes and the other 4 fire the cylinders.
A weird setup, but the engine runs smooth when it's all correct.
I believe the actual firing marks are about 45 degrees on either side of the top of the fan opening.
 
Just to add, If your engine is an oddfire V4, I found instructions for timing it using the search engine on this site.
 
Jon,

I looked and couldn't find the instructions? I believe it may be an odd fire, the rotor is directly attached to the mag shaft, I wanted to replace it way back and could figure out how to get it off. Could you direct me as to where the instructions are or post them for me?

Thanks,Scott
 
It doesn't so do you think the crank and all that stuff is screwed up? Is there a way to leave as is and time everything else to this?If not is it a big job? Are we talking a total engine tear down?
 
This may help, I believe this drawing is of the oddfire motor by the looks of the mag.
a129320.jpg
 

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