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Dizzy set up

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jlaird

jlaird

Great Pumpkin
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Am I correct in that for setting the dizzy, the #1 piston would be all the way up and the #4 all the way down with the timeing mark on the dampner at 7 degrees? Now the roter should point at the front wire, about at the #1 plug in fact?
The reason, of course, that I ask is that engine is out and I wish to make sure it is not 180 out. Do I remember correctly or am I all wet?

Associated question and what brings this up is that puts the vacuem advance on the Dizzy at a strange angle unless and maybe I dis remember, there was a rubber angle peice attached to the Dizzy vacuem fitting that corrects for that strange placement? LOL and it is Moss # 153-840 however your commens per the above might let me sleep better. /ubbthreads/images/graemlins/hammer.gif

Strange how setting here typing this helps to work it out in my mind, all kinds of Bugeye trivia come from someplace but I am never quite sure if I have it correct or not till you guys set me straight.
 
Jack, Doc answered this over in the MG forum, but let me add that TDC is when the timing mark is lined up at 0, not 7 degrees. Install your distributor in this position, and then static time it to the 7 degrees, or whatever setting you prefer.
Jeff
 
If the dizzy vacuum advance is not where you want or need it to be... pull the dizzy again and thread a 3/8-24 bolt into its drive gear in the block. Use the bolt to pull the gear then rotate it slightly and put it back in the block. Then re-check your dizzy position.

As Jeff said, with the pistons at TDC, your timing mark should be at zero degrees. At 7 BTDC the valves will be "close" to what they are at TDC but not exactly the same position.
 
[ QUOTE ]
Am I correct in that for setting the dizzy, the #1 piston would be all the way up and the #4 all the way down with the timing mark on the damper at 7 degrees? Now the rotor should point at the front wire, about at the #1 plug in fact?
The reason, of course, that I ask is that engine is out and I wish to make sure it is not 180 out. Do I remember correctly or am I all wet?

[/ QUOTE ]
Jack, I'm sure it is just a missprint. Number 1 & number 4 pistons will both be all of the way up. It's the way that the crankshaft is arranged. One of them on the firing stroke & the other on the exhaust stroke.

If #1 is at TDC firing, both of it's valves will have their normal lash (play) & the valves on #4 will be partially open, at the top of their exhaust stroke, no lash. The rotor should be pointing to #1 plug wire.

The timing mark will also show TDC with #4 on the firing stroke, ie. the cylinder #4 valves will have lash & #1 valves tight, which is 180 out on the distributor, or 360 out on the crankshaft. Not correct, unless the rotor is pointing to #4.

Jeff & Doug are right on about the rest of it.
D
 
Ok, think I got it. Heh, we will see when I get the tub back and get a chance to fire it up.
 
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