Distributor cam orientation

[Art Bailey]

Stupid questions of the day follow.

 

During the careful blowing apart of my '48 DeSoto's distributor for cleaning, I noticed (too late) that the cam can be oriented two ways on the shaft, when engaged with the flyweights. The plate for the flyweights on the shaft has an "R" on it, near the lighter spring.

 

The cam has an "R" embossed in it on the underside, too.

 

 

Are the letters supposed to help with orienting the cam? Or, does it even matter? There's also an "O" embossed on the opposite side of the cam. I'm also noticing wear on the lower rectangular hole on the cam, where the flyweight shaft must rub when the flyweight flings out...that could be a clue to how it was installed.

 

Art

Edited March 19, 2021 by ratbailey

[Conn47D24]

Interesting, I do not recall any difference assembling my dizzy. 

 

1st thought is the engineers made some of this idiot proof for people like me.

Seems there would be a difference in the notches,  and posts if it mattered. 

 

[desoto1939]

I just looked in my 1936-42 Desoto Master Parts book in the distributor section and here is what i found.  There are 2 required distributor weights and both are the same number and a weight sprint set and the saem number was used from 1936-41. It shows one set so from that I think that there are two springs and they would be the same.

 

Hope this helps I can only check against what my Desoto books show but you might look into your specific year parts book to verify.

 

Rich Hartung

Desoto1939@aol.com

[Art Bailey]

1 hour ago, desoto1939 said:

I just looked in my 1936-42 Desoto Master Parts book in the distributor section and here is what i found.  There are 2 required distributor weights and both are the same number and a weight sprint set and the saem number was used from 1936-41. It shows one set so from that I think that there are two springs and they would be the same.

 

Hope this helps I can only check against what my Desoto books show but you might look into your specific year parts book to verify.

 

Rich Hartung

Desoto1939@aol.com

Hi Rich...my books don't mention different sized springs, but the 1947 tech bulletin does...

However, no mention of which way the cam mounts. I'll see if I can guess how it was in there by the wear on the slots, though it's looking like it might not matter. 

[desoto1939]

As the repair manuals got better with information it is great to see that as time went on the companies started to supply more detailed information in their respective manuals.

 

Thanks for posting the section on the mechanical advance info.

 

Rich Hartung

[49WINDS]

I had torn apart my whole distributor last fall and never even thought to take note of which way the cam was orientated. I did have excessive wear similar to yours on one side but I actually ended up finding a used dizzy that was in good shape and took the parts I needed out of it. I thought someone on this forum had said the letters just notated slightly different timing curves but looking at mine I noticed the are different letters on the base plate versus the cam. I think matching up the more worn sides is a safe bet to putting it back how it was though. As you mentioned in your previous comment though I think it doesn't really matter as the only real difference is the strength of the springs.

 

 

[Art Bailey]

1 hour ago, 49WINDS said:

I had torn apart my whole distributor last fall and never even thought to take note of which way the cam was orientated.

I swear I will never learn this lesson. If there's more than one way something can be reassembled, I will never notice until after the fact. At least I'm consistent!

I don't know if the wear is so bad as to warrant looking for a better one, but so far, it's the most haggard piece on this car. It also gives away the fact that the engine wasn't really rebuilt, as the seller told me, but more likely just honed and re-ringed. It was so frozen to the engine with rust and crud, there's no way that that dizzy had ever been separated from the block in the last 70 years. 

Edited March 20, 2021 by ratbailey

[49WINDS]

19 hours ago, ratbailey said:

I swear I will never learn this lesson. If there's more than one way something can be reassembled, I will never notice until after the fact. At least I'm consistent!

I don't know if the wear is so bad as to warrant looking for a better one, but so far, it's the most haggard piece on this car.

Haha well it's good to know I'm not the only one who just dives into pulling things apart and has to figure out reassembly later!

 

The cam on yours looked in much better shape than mine did, although I think the only reason I found my issue was because I heard it rattling inside when I had it apart for upgrading to pertronix.

[Sniper]

That is some wear there.  Wonder how this would work for our stuff? 

 

http://www.4secondsflat.com/Mopar Mechanical timing limiter plate.htm

Edited March 21, 2021 by Sniper

[Pipelineroutlaw]

Can someone tell me which distributor Will work with my T306- I currently have distributor #iGS-4109-1 and it has fire at the plugs but won’t start. I got it started for about 10 minutes but it didn’t run right under a load and now won’t start. Any help will be much appreciated!

[P15-D24]

1 hour ago, Pipelineroutlaw said:

Can someone tell me which distributor Will work with my T306- I currently have distributor #iGS-4109-1 and it has fire at the plugs but won’t start. 

You sure on that 4109-1 number? I don't see one listed in the Hollanders Interchange manual. Also what is the vehicle? T306 was in a B3 and B4 truck (218ci) but you sig shows Powerwagon which would be a 230ci. 

[Pipelineroutlaw]

I’m guessing the engine has been changed at some point in it’s life. I’m positive on the distributor number but, are you thinking it won’t work with this engine?

[Pipelineroutlaw]

31 minutes ago, P15-D24 said:

You sure on that 4109-1 number? I don't see one listed in the Hollanders Interchange manual. Also what is the vehicle? T306 was in a B3 and B4 truck (218ci) but you sig shows Powerwagon which would be a 230ci. 

Thanks 

[P15-D24]

I will check again to be sure, but Hollanders Interchange does not show that as a distributor you can swap in. 

[Pipelineroutlaw]

Any idea which distributor I need and where to get it?

 I really appreciate you helping me with this issue.

[Plymouthy Adams]

the question is, did you exact a tune up....and if so, did you order parts by model and year or did you order parts by distributor number.....all the parts do not interchange 

[Pipelineroutlaw]

Had the distributor professionally rebuilt after this happened I ordered parts by distributor number thinking they didn’t but, turned out everything was right.

[kencombs]

3 hours ago, Pipelineroutlaw said:

Any idea which distributor I need and where to get it?

 I really appreciate you helping me with this issue.

There are guys here that know a lot more detail than I, but AFAIK, all distributors for 218/230 engines will work.  There may be differences in internal parts and/or timing curves but physical fitment is all inclusive.  ie;  it should run with any distributor that fits.

 

Some have no vacuum advance (trucks or industrial usually), some have no mechanical advance (welder or air compressor power units), but they fit.

 

My old Hollander seems to confirm that.

 

If it were mine, I'd just get it to run and modify weights, springs and vacuum to arrive at the advance that makes it perform best in my use.