can this be possible???

mike paulson · Jul 2, 2010

i'm doing a tune up on my 300u and pull the cap and turn the dist shaft up to a high spot to check the points before i pull them and the gap is "get this" about 1/8 inch????
can anyone explain how the heck this thing was even running????the spec is .020

Andrew Z · Jul 2, 2010

I had the same thing on my H years ago when i got it. Stuff just loosens up and points wear and thus a big gap. Hard to beat these old machines.

Andrew

mike paulson · Jul 2, 2010

the thing ran great with a gap the size of the grand canyon, wow with new plugs and the correct gap it should run like a porshe!!!!

CNKS · Jul 2, 2010

Usually the gap will get narrower due to wear on the rubbing block. Could be the previous owner did not get them on the high spot when adjusting. Yours were "only" off by 0.105.

mike paulson · Jul 2, 2010

yea he might not have tightened the screw which cause the huge gap, i cranked the new set in pretty tight.

Wayne in MN · Jul 2, 2010

You may have to re-set the timing now that the points are set correctly. If the timing had been set with the wide gap by previous owner, now the timing will be very late and the engine will not have much power since the point cam will rotate further before opening the points.
Good luck.
Contact me if you need help.

mike paulson · Jul 3, 2010

yes i'm gonna head out in a little to finish this tune up, didnt start it yet. i'll probable throw the timing light on it anyway and take it for a spin to make sure it's right. i will post with results later.....thanks

Sam#3 · Jul 3, 2010

Did the points close? I don't suppose the engine would run too well but all the points are required to do is close and open. The gap sets the duration of the coil saturation and decay which on a four cylinder needn’t be that precise.

pete 23 · Jul 3, 2010

I agree 100%, gap on 4 cyl battery ign system is not at all critical, we just like to set them where they are supposed to be. If it was a higher rpm v-8 engine you need to be very precise and normally set them by degrees of dwell. On a magneto it is whole different ball game, need to be precise because spark lag is in direct relation to point gap due to use of an impulse.

mike paulson · Jul 4, 2010

yes they did close even with that gap, i put new points in checked the timing made a slight adjustment and all is good...

can this be possible???

mike paulson

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Andrew Z

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CNKS

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Wayne in MN

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Sam#3

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