how to tell if the distributor drive gear is installed correctly?

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22dog22

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Have been chasing my tail on my 69 Barracuda, 318, auto, have posted other questions. Last installed was a Pertronix Distributor with there Ignitor II module and there correct coil, [ no resistor, full power to the coil and dist, per there directions] with that I was able to have car start, but ran horribly and would just keep getting worst till it would shut off, pull plugs some showed that some where not firing, some had carbon, #8 was covered with gas after about 30 sec. run time.

Gave up on the Pertronix unit {after replacing the unit in the dist. also}.

Read on here about Ricks Mopar, I am trying one of his Mopar style dist. and ecu unit. Followed his instructions, had the engine timing on 10deg. before , as per the Instructions, marked #1 rotor was pointing . My question is at this point, the rotor for #1 is almost facing the fire wall, everything I read it should be front/left front, anyway now I seem not to have spark, when I crank the engine wants to jam?, tried to play with the timing a little advanced/retard but stays the same, just to review I had in a cheap Pro Comp dist. and there coil, the ran for about 3 years, then over last winter I had a battery tender hooked the battery over the winter,[ had cables hooked up , my error] which seemed like it took out my electronic voltage reg. [ have updated to a dual field alt. and wiring for the electronic reg] ,which I was sure caused the coil and the dist. to fail, car would run but had to give it gas to keep it going at a stop sign, till by the end of last year it stopped running. I had my friend help me, when I installed the Pertronix unit, [ dist. and matching coil], got the timing mark to tdc, and again the #1 on the rotor was toward the fire wall, as stated I have about 500 miles on the engine since a total rebuild by a local Mopar person. I am questioning could the gear that drives the dist. be off??

Have ruled out a carb/fuel problem, [ new Holley carb, old known good carb] check for poor connections/corrosion, have correct voltage to coil and the new resistor , ignition switch was checked no problem. [ as stated car would fire right up with Pertronix unit ] have pulled the spark plugs did compression test 150-155 on all cylinders. I just me seems like some type of timing issue, that is why I ask about the dist, drive gear, engine has only 500 miles, a new timing gear, chain was installed and the engine ran [ again after total rebuild, bearings, Keith Black 167 pistons, 30 over, Comp Cam, heads redone, new harmnic bal.] for 500 miles.
 
If #1 cylinder is on the compression stroke the rotor should be pointing at the #1 cylinder. As you stated, front left. 65
 
Actually, according to the service manual, the slot in the intermediate shaft should point to front most intake manifold bolt on the driver's side and the rotor should point basically straight to the front, when at TDC for #1. I always install that way, because it allows for the most movement of the distributor in regards to the vacuum advance. Read the service manual. That's how you figure it out.
 
with #1 cyl at TDC on compression stroke.


1726770944657.png
 
with #1 cyl at TDC on compression stroke.


View attachment 1716305292


This is ONLY and IF the rotor and the drive tang are in line.

99% of the time they are not.

Telling people to use the FSM and not telling them that it almost never works is not good.

I’m betting I have 30-40 distributors laying around and not one of them has the rotor lined up with the drive tang.
 
This is ONLY and IF the rotor and the drive tang are in line.

99% of the time they are not.

Telling people to use the FSM and not telling them that it almost never works is not good.

I’m betting I have 30-40 distributors laying around and not one of them has the rotor lined up with the drive tang.
They'll figure it out. We had to figure it out with NO internet and nothing BUT the service manual and MP manuals and such. We actually had to DIG for it, instead of having it spoon fed.
 
This is ONLY and IF the rotor and the drive tang are in line.

99% of the time they are not.

Telling people to use the FSM and not telling them that it almost never works is not good.

I’m betting I have 30-40 distributors laying around and not one of them has the rotor lined up with the drive tang.

i've never had an issue lining things up like the service manual.
 
So what he is saying is that on some Distributors the Rotor may not point straight ahead like it is "supposed to." The illustration in post #5 is where the Drive Gear should point. The Rotor should point straight ahead toward the front of the car. The Distributor is technically not correct if it points in another direction, but you can make it work. The plug wiring will be different though. Send us some pics
 
They'll figure it out. We had to figure it out with NO internet and nothing BUT the service manual and MP manuals and such. We actually had to DIG for it, instead of having it spoon fed.
yeah! and hamburgers were a nickle and them nickles had pictures of bumblebees on 'em!

*blows the dust off the tome of FSM's on the desk*
*ties onion back on belt*
 
I will grab some photos, I did have the timing marks on the engine at 10 deg. before, marked where the point of the rotor was facing , and dropped the new dist. the same way. Did not have the cranking issue with the Pertronix unit, it did at least get the car to start, but just could not keep it going, seemed like I was loosing spark till it would die, with this new one, I have no spark and a cranking issue now.
 
hey'll figure it out. We had to figure it out with NO internet and nothing BUT the service manual and MP manuals and such. We actually had to DIG for it, instead of having it spoon fed.

There was no innerwebz back in the day, so we used to go to a magazine store or Pep Boys and read their Chilton manual, cuz we were too broke to buy our own copy..
 
The facts are these, and we've joked about this. One member used to say, "the gear could point to China." You COULD do this:

1 Throw the gear in any old way

2 Throw the dist in either way

3 Pull no1 plug. Stick your finger in, bump the engine to find compression. When you JUST STAT to feel compression, STOP and look for the marks. Wrench or bump the engine NOT TO TDC but rather WHERE YOU WANT timing AKA maybe 12-15BTC.

4 Now, if you have points, rotate the dist body CW (retard for a SB) and then back again slowly (advanced) until the points open, or if you have breakerless, visually center the reluctor in the pickup coil

5 NOW look at where the rotor is. Plug the no1 wire into the tower which the rotor is JUST approaching, plug in the rest of the wires re: no1 and START IT UP

I am NOT saying you should do that, as the plug wires won't lay correctly necessarily, and the vacuum advance might not be "in the clear" but the timing WILL be right and it WILL run, assuming no other problems
 
Ok, I have an update, heard back from Rick at Rick's Mopar, asked if that I had power on both the crank [ brown wire] and run [ blue wire] again I am surprised even thought I had power for crank with the Pertronix system I just had in the car, and it would start , NOW I have ZERO power on the crank [ brown wire], checked all the way back to the ignition switch no power out of the switch, this is the only part I have not replaced, but I always had power on the crank and run wires. So I just ordered a switch from Danates Mopar parts. We see what happens after I get this installed.
 
There is no wrong way to install the drive gear; but there is a factory correct orientation of the drive slot for a correctly oriented drive tang.
On some of the Chinese distributors the drive tang is like 90* different from the factory, which then orients the rotor that far out, if the drive slot is correctly oriented.
None of this matters if the wires are long enough to be re-clocked, or unless there is some OCD involved.
The engine will run no mater where the rotor is pointing, so long as at #1 TDC compression, the #1 wire is plugged into whatever tower is directly above the rotor-tip, when the pole-piece is aligned to a vane.
 
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