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Old 07-22-2011, 07:13 PM
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Today, I got the MSD and distributor put in and wired up. I had a local mechanic stop by and check out the wiring. He said everything looked fine and he tested it to see would it fire and there was spark. The problem however was that he said I had the wrong dist. cap. So he sent me down to NAPA to get a different cap. When I got back and put that cap on, the number one was in a different location. So I put the wires on based off of where I knew the number one point was at when I put it at TDC. Well, the car turned over twice, but both times I got back fire. Now, when I hit the ignition, I'm getting nothing. Does anyone know what the problem could be? I'm thinking that maybe I have my wires on the dist off. If so, how would i be able to find TDC now, after the crank has been turned several times?

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Old 07-22-2011, 07:58 PM
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Pull the #1 spark plug, bump the starter until you feel the piston pushing your thump off the #1 spark plug hole.....that's the compression stroke, if your balancer markings are correct, turn by hand until the TDC mark lines up with the pointer....look at your rotor under the dizzy cap, that's where the number one wire should go.

Was it a new MSD or used?
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Old 07-22-2011, 08:16 PM
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It was used. When I bought the car, it was already hooked up.
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Old 07-22-2011, 08:23 PM
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Did it run before you chg'd the cap? If so you might have gotten the wrong cap, seems strange that it it ran before and the new cap was diff....... I'd go back to the orig cap
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Old 07-22-2011, 08:32 PM
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It did'nt actually run, the mechanic just took a screwdriver and put one to a plug wire and took one and taped the selonod to see would it turn over and it did. It turned over twice with the new cap, but never caught just backfired. What would cause the backfire, and I thought I smelt something burning.
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Old 07-23-2011, 06:20 AM
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dizzy could be incorrectly indexed, 180 degrees out, firing order messed up ( not starting at #1 cyl at TDC and the rotor at the #1 post) My advice is to pull all the plug wires, pull the # 1 plug, get it at TDC on the compression stroke (this is where it could be 180 degree off) look under the dizzy cap and find where the rotor is pointing (to determine the # 1 post)

(get on line and see where the #1 post should be, if it's way off pull the dizzy and re-index it so the #1 post ends up close to where it's supposed to be) Don't turn over the engine!

Reattach the plug wires one at a time (from the dizzy to the plugs) following the firing order for your engine. If your ing sytem is good it should fire, if it runs ruff - adv or retart the timing (by rotating the dizzy) untill it runs smooth, get a timing light and adj to the specs for your engine.

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Old 07-23-2011, 06:28 AM
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Thanks for the advice. Two questions though:

1) The orignal factory distributor had the #1 plug located between the 11 and 12 o'clock position. This new duraspark distributor has the #1 terminal at about the 1 o'clock position. It's a distributor for a '78 Mustang and there's no way to rotate the cap around to the 11 - 12 o'clock position?

2) As I have my thumb over the #1 sparkplug hole, will it be obvious between the exhaust stroke and compression stroke to make sure it's at top dead center since I cannot go off the number one on the cap?
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Old 07-23-2011, 07:05 AM
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which engine ?

If you have a V8 there are TWO different firing orders between std small blocks and the 351 W -5.0 Ho engines, some one could have installed a cam with the HO firing order, In that case you need to first find No 1 TDC then the next cylinder in the firing order to verify which firing order you have. Then you can plug in the wires in the correct order . On the early buick V 6 engines there are odd fire engines, the cylinders DO NOT fire 120 degrees apart. On those engines the distributor position, rotor position and spark plug wires must be in the correct position per the manual. or you can have 3 cylinders firing correctly and 3 cylinders off a few dergees. turning the distributor to time the engine just moves 3 cylinders out of time and 3 cylinders into time. and you don't notice any difference in the way the engine runs.
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Old 07-23-2011, 07:12 AM
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Its a 302. The firing order was the normal 1-5-4-2-6-3-7-8
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