Distributor Wobble - Intermitent Spark

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NH69Valiant

NH69Valiant

Well-Known Member
Joined
Jun 18, 2014
Messages
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Location
Central NH
1968 318 Block
Just put this in my 69 Valiant (former /6) and when I went to fire it up I realized the was no (very little) spark. I ordered a new MP distributor and installed with the same result.
I had a friend come over to check it and he noticed that the distributor was Wobbling when we cranked the engine. Tried it with the old distributor with the same result.
What would cause the distributor wobble???? :banghead:

Thanks for any help
 
Sounds like the distributor is not seated correctly. There is no way it should move at all if installed correctly. Is the slotted tip of the distributor lined up with the one in the oil pump drive gear?
 
I don't know if the motor is fresh or was running before, but you might check the bronze bushing the dist drive slides through, if its not seated all the way down it will hold the dist up a little. IMO if the dist hold down is tight and the dist shaft is straight something's holding it up a little.
 
As far as we can tell it is. My friend is a certified Tech and he was doing the install with me. He does not have much experience with Older Mopars as he is GM certified. We tightened it down good with the same result.
 
The dist should sit flat even without the hold down on. If you feel its not, maybe try to slip a feeler gauge under it, you might want to pull the intake and get a good look at whats going on. If you can fish the dist drive out you can try to tap the bushing down before you pull the intake. If it was me I probably would do that first. You can fish the drive out with a properly bent coat hanger and some patience.
 
I have seen occasions where the slot in the drive gear is offset a little and or the same on the tab on the bottom of the shaft. Have you tried turning the shaft 180 degrees and see if the problem is still there or changes? You can always rewire the cap or turn the drive gear 180. You may have to get a new drive gear/shaft unit.
 
If it was wobbling with the old distributor and with a new one also, the distributor is not seat properly. I don't think the slots are lined up between the distributor and the oil pump drive gear ( which will also cause the loss of ignition spark ).If they are not lined up and seated together properly the distributor won't seat properly. I have seen where this has happened and the hold down clamp was tightened until it broke the retaining collar on the distributor shaft, which lets the distributor housing slide on down and look seated ( but it is't ).Which also pushed the rotor button upward toward the distributor cap.
 
Duster 360 you make me think that perhaps for what ever reason the distributor shaft could also be bottoming out in the drive gear before the housing flange is seating on the block. The addition of gaskets under the distributor may solve this as well.
 
may be as simple as something has fell into the pump drive slot

look to see that it is clean.

or the distributor housing is binding against the intake
 
Had a Dakota v6 that did the same thing. Turned out it was the bronze bushing was wore out.
Replaced it and it ran fine.
 
Yet another timely thread. I just ran into this on a late 318-4 in my 72 Charger. No matter what I changed out, I couldn't get a spark. Last time I was down there, I noticed the wobble. I changed out the entire dist, and still there. It was kind if difficult to seat, but didn't look too high. This is the firts time I've ever run into this, but my next move is to suspect something was going on with the slot, now I'm convinced. Next move is high powered flashlight and coat hanger.

Thanks
 
Chuck the distributor shaft in a 1/2 drill chuck and spin it, if it wobbles the shaft may be bent. I have found that to happen often, especially if the distributor has been shipped, or dropped.

Also the distributor needs to fit, to seat at top of block. If there is a slight gap and the hold down is used to pull it down, it will wobble. Solution may be to clean bottom of gear slot, or shorten shaft slightly. I tested a Skip White ready to run, and found the shaft was too long.
 
There was another thread on same topic within the last month or so.
I really don't remember what that owner found. Might have been excessive RTV at intake sealing. Try search. Good luck
 
Got it Running!!! :cheers:
Turns out that the distributor wasn't seated al the way down on the block. When we got home this evening my freind tapped it down into it's seat with attitude and it snapped in. We couldn't believe the clamp wouldn't have forced it into the block. It fired up immediately and sound pretty healthy even without any tuning or timing.

This forum is the best and a BIG THANK YOU to everyone that posted on this subject. I also want to thank everyone that makes up this Great Forum
I'm new to Mopar and it has been years since Iv'e tinkered with any thing automotive and getting the Motor Swapped in the Valiant would have been much more difficult without the endless resources on this board.

Have a great weekend all,
Dave
 
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