'37 Buick distributor movement = loss of spark?

[BenT]

Hello, I am new to the group and appreciate the chance to rely on your experiences and know how.

I had the distributor for my 1937 Buick special straight 8 rebuilt recently, got it installed and tried to crank the motor over. Experiencing a loss in spark.

Popped the cap off and tried cranking the engine and noticed on this video I've uploaded to youtube that the distributor plate seems to move at 0:14 - 0:16.

Dumb question first: Is that supposed to happen? I think probably not.

How do I prevent that from occurring if that is the cause of my spark loss during start up? I think I see a machined hole off the to the top of the image.... should a set screw be in there?

Did I just install the distributor shaft incorrectly altogether? 

I greatly appreciate any insight into this oddity.

 

Edited January 19, 2021 by BenT (see edit history)

[Bloo]

I don't know about the plate. It seems to be moving up and down? The vacuum advance rotates the plate around the shaft during normal operation, so it wouldn't be locked solid. It has been years since I have seen one of those distributors apart. As I recall, there are 3 ball bearings that hold it in place up/down but still allow the vacuum advance to rotate the plate around the shaft. Perhaps one is missing.

 

There is also supposed to be a ground wire from the plate to the distributor case. It is a special wire made of copper and spring steel strands, because it gets bent constantly as the plate moves, and needs not to break. You need to add that for sure.  Bob's Automobilia might have it, but if a real 37 Buick wire is not available, similar wires were used on GM cars and Fords up into the early 70s and you should be able to match something up. The insulated wire running from the post to the points is another similar special wire that needs to deal with constant bending, and it might make sense to just change it too if they are available. At the very least make sure it is not broken.

 

The points should ground the coil as they close. You could connect a test light from the distributor terminal to ground (but fix the breaker plate ground wire first). It should go on and off as the points open and close. If not, does it stay on or stay off?

 

 

Edited January 19, 2021 by Bloo (see edit history)

[MCHinson]

I would return to whoever "rebuilt" the distributor. They need to fix it correctly. The plate should not be moving up and down like that. It looks like the plate is not installed correctly as the ball bearings should prevent the up and down motion. Bloo is correct about the wires. I also always question new condensors. I have seen new imported condensors that were bad out of the box. A good old stock condensor might be a good investment even if the new condensor is not part of your current problem. 

[TexasJohn55]

At that cranking speed, it will never start anyway. Put a "hot" battery on it or fix the voltage drop to the starter. You cannot crank an engine off a 30 amp battery charger. You will toast that starter.

[Bloo]

Battery charger? I missed that part somehow.

[TexasJohn55]

51 minutes ago, Bloo said:

Battery charger? I missed that part somehow.

CLICK....CLICK of the overload circuit breaker.

 

There is another 16 sec video of "first attempt" to start.

Edited January 20, 2021 by TexasJohn55 (see edit history)

[37_Roadmaster_C]

I agree with the above. The plate should not be moving up and down. If you are trying to use a charger to do this test it is very likely the starter is drawing the voltage down so far it will not spark. Get a fully charged proper battery. You will need one anyway when you get it running 😀.

[Oldtech]

Looking at the points, it looks like they are set too wide, Are they closing at all?

 

[BenT]

Thank you for the input! 

It does appear my points are opening and closing - but could use adjustment - closer. Thank you. I will try that.

I am trying to crank the car over with a new 6Volt battery which is installed. I agree - it doesn't seem to crank fast enough. Perhaps it should spend some time on the charger or I should look at something with more Cold cranking amps.

As for the distributor plate - I have to figure out where and how it should be secure. Knowing its not supposed to be doing that - I can approach the mechanic who rebuilt it and ask him what is wrong or not secure.

 

I will also address the wires and report back with an update soon.

 

[MCHinson]

Regarding the slow cranking, make sure you have nice clean tight connections on the battery cables, and that they are the correct sized cables. The cables that you commonly find at auto parts stores that are designed for 12 volt systems will not carry enough current to correctly turn a 6 volt starter. Another common issue is the starter mounting bolts should be clean, paint free, and tight to provide a good ground. A separate heavy ground wire from the chassis to a starter bolt is also a good idea.  

[pont35cpe]

There is a hard to find DynaFlyte 880 breaker plate(this is an excellent upgrade from the 3 ball pivot type)in "parts for sale".

 

[Oldtech]

The plate movement isn't bothering me at this point. Get it sparking first. The plate has to turn with the vacuum advance . above upgrade might make you happy. 

These engines don't crank fast by modern standards but yours seems a little slow.

[dracenroc]

Just a thought: I converted my '38 to electronic ignition. Since I try to keep everything original it hurts a little in the heart but i have never regretted this step with all my old vehicles.

[Bloo]

Don't do it. Converting a car to electronic ignition to solve a problem is a very bad idea. The car worked when it was new. Adding more levels of complication to a broken car is just digging a hole for yourself. This car is a perfect example.

 

As noted above, the ground wire on the breaker plate is missing. The ground wire completes the circuit for the points, firing the coil. It may very well be the reason for no spark if the plate is not making contact some other way. If the plate is making contact, it may not continue to make contact when the vacuum advance moves it. The vacuum advance moves it a lot.

 

The original-type Pertronix, (a common electronic ignition conversion for old cars like this), fires the coil by grounding it through the breaker plate (and it's ground wire) exactly as the points did. It also depends on that same ground to power the electronic ignition circuitry. Additionally, any defects in the centrifugal or vacuum advance mechanisms will still exist after conversion because it is the same distributor.

 

I often wonder how much of the Pertronix hate I see in this forum and elsewhere results from situations exactly like this. In my opinion, fix the car first. If electronic ignition is wanted, add it after the car runs right.

.

Edited January 26, 2021 by Bloo (see edit history)