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Old 01-07-2011, 08:44 PM   #1
wxman1
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Setting Up The Dizzy

I'm installing a new Accel distributor in my 69 C10 P/U. Probably should have marked the position of the rotor before pulling it out...but I didn't. So I set the #1 cylinder at TDC using my whistler gadget. I insert the dizzy with the rotor roughly pointing at the #1 cylinder post.

I've attached a diagram to illustrate what I'm talking about. Initial attemp = no start.
I rotate the dizzy in the direction indicated in the diagram. I do this twice and it fires up.
I get the timing light out and check timing. Its firing right at TDC. Well...according to the sticker on the fender...it needs 4-6 degrees BTDC. Well the problem is...the vacuum can
is up against the intake manifold...so I can't turn the dizzy any more.

In order to correct this situation I assume I have to pull the distributor out to disengage the distributor shaft and rotate the shaft in the opposite direction in order the get more adjustment in the BTDC direction. If you have any experience at doing this let me know
if this is correct.

Jim
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Old 01-07-2011, 10:03 PM   #2
hugger6933
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Re: Setting Up The Dizzy

Jim your thinking is right on. You need to pull the dist out and move it one tooth so you can get the advance you need. If you pull the dist all the way out you may have to turn the oil pump driveshaft with a screw driver so that it will engauge after you move the dist. If not when you move it back you will have a small gap betwwen you dist base and the intake . you can also bump the motor over until it drops, then bring you marks back up and then check your timing agian. If you can read the marks on your timing tab bring it up to the 6 btdc mark ,turn the dist back and forth [cap on key on ]number one plug wire hooked up to a spark plug on top of the manifold until it sparks at the point that it is sparking there is your"static' timing. Jim
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Old 01-07-2011, 10:08 PM   #3
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Re: Setting Up The Dizzy

sorry for the in the middlie of my reply
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Old 01-07-2011, 11:00 PM   #4
jcis4me
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Re: Setting Up The Dizzy

Aloha Jim
In order for mine to even show on the balancer TDC I think I have to move the plug wires one hole over. I have tried to move the dist one tooth but to get the right timing mark I need to either remove the vaccumne advance so it doesnt touch the intake, or move the plugs one hole over. I have no idea what the PO did when he built this motor but I am finding out he didnt know what he was doing,mostly just bolt on HP parts ond not tune em correctly, err go the timing mark so far off. There is an old GM guy here on the island and he says to move the plug wires one hole over, want to try this this weekend to see if I can get the timing mark correct.
Aloha
Marty
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Old 01-07-2011, 11:28 PM   #5
CCCC
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Re: Setting Up The Dizzy

In that you did not mark the position when removing the old dist , and especially if the plug wire positions on the old cap seem to confirm the "one off" positioning, you probably will get success doing that move - with some positional adjustment of the dist to get #1 at TDC. Previous poster gives a good decription of how to do that for "static" setting. best wishes.
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Old 01-08-2011, 09:03 PM   #6
wxman1
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Re: Setting Up The Dizzy

Thanks for the replys. I was thinking about hugger's reply. Is it even possible
to pull the distributor out enough to rotate the gear one tooth without disengaging the
oil pump. it seems to me that both the gear and the "blade" inside the shaft would
disengage at the same time.

I do have an old distributor shaft...I guess I could use that to reposition the
oil pump slot. If my calculations are correct(13 teeth/360 degrees) moving
one tooth would move the timing 26 degrees approximately.

Jim
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Old 01-08-2011, 09:55 PM   #7
hugger6933
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Re: Setting Up The Dizzy

If you lift the dist enough to disengauge the drive gear, you will also but out of the oil pump driveshaft. Like I said earlier in this if you move the dist back one tooth just 'bump' the engine over until the oil pump is engauged agian. Then you can go back to #1 tdc and check yourself. You could also try "walking" the wires around[ 1to8 8to4 4to3 and so forth]. If you walk the wires you run the risk of going to far the other way, I think that may be like moving the dist about 3 teeth on the gear. Good luck if I have good and really confused you I am sorry let me know it and I'll try to clear it up for you . Jim M
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Old 01-08-2011, 10:08 PM   #8
wxman1
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Re: Setting Up The Dizzy

I probably won't try and move wires around. That would be an invitation to disaster.
So if I'm understanding you right...after moving the dizzy one tooth and re-inserting the dizzy
it obviously won't drop into the oil pump slot since that is not now in the same position.
So then I turn the crankshaft until the oil pump shaft again lines up and the dizzy drops in...
right? Are we talking about only turning it a few degrees?

Jim
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Old 01-08-2011, 10:25 PM   #9
jamesi20
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Re: Setting Up The Dizzy

NO,don't turn the crankshaft...turn the oil pump slot with your old dist shaft
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Old 01-08-2011, 11:54 PM   #10
wxman1
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Re: Setting Up The Dizzy

OK...got it. Thanks for the help!

Jim
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