Thread size on the distributor shaft to tighten the cam screw?
 

HELP, Any body know the thread size of the distributor upper shaft where you tighten the cam screw into??? the thread on the cam screw???
Thanks,
Ken:D

Re: Thread size on the distributor shaft to tighten the cam screw?
 

5/16 X 24 ought to do it.

Re: Thread size on the distributor shaft to tighten the cam screw?
 

No John, That is what I tried and it screwed up the threads inside the shaft. I tried my thread gauge on it and i cannot find a size to fit????
Really wierd,
Ken

Re: Thread size on the distributor shaft to tighten the cam screw?
 

Is it Metric?

Re: Thread size on the distributor shaft to tighten the cam screw?
 

I have a very old thread guage that belonged to my great grandfather,he had a machine shop but was an engineman/machinest in WW1.Years ago I was playing with a shaft with screwed up threads and found nothing to fit it.I checked it with his old guage and did come up with the proper one,but it was such an oddball I could not find a tap.I forget what it is,but the guage is in the toolbox draw and there is an old dist.shaft in with it.The shoulder on the shaft is turned to drive out the old bushings.It is a tool that happens to sleep with the thread guage.I will try to remember to check it when I go to the garage tomorrow.

Re: Thread size on the distributor shaft to tighten the cam screw?
 

I am leaning that way also. I measured it to be 8 MM O.D. but i do not have a metric thread gauge so it will wait til tomorrow.
Thanks to all for trying to help,
Ken:D

Re: Thread size on the distributor shaft to tighten the cam screw?
 

If you could wake up that old tool tomorrow I would be thankful,
Ken:D

Re: Thread size on the distributor shaft to tighten the cam screw?
 

Why don't you just call Walt Bratton, they sell the new shafts, cams and cam nut ?

Walt is always very helpful to us Aers !!!!

Ron

P.S. I do not know the thread size !!!

Re: Thread size on the distributor shaft to tighten the cam screw?
 

It's an oddball thread alright. It's 5/16 x 30 tpi. When I first measured it, I thought it was 5/16 ME, which is 32 tpi, but when I tried my tap by hand, it screwed in about 3 turns and stopped. Got out the thread guage, yep, 30 tpi, I tried 26, 28, and 32, but 30 is what it is.

Re: Thread size on the distributor shaft to tighten the cam screw?
 

Dave, you boys were hit with some SEVERE flooding down under :eek:
That's gotta mess-up one's life...are you OK?

Re: Thread size on the distributor shaft to tighten the cam screw?
 

Thanks for your concern Craig. The floods are in central Queensland, which is approx 1500-1800 miles north of where I live. The area affected is the size of France and Germany combined, about 400,000 square miles. Queensland is Australia's second largest state, about 715,000 square miles or about 1/4 of Australia. The area in Australia where I live is more affected by bushfires than anything else, which thankfully none have been started yet.

Re: Thread size on the distributor shaft to tighten the cam screw?
 

The Parts Price List has this A-20744 listed as .325 - 30.

Ken, I'll bet you have the "Parts Price List", but for those who don't, it's a very good book to own. I think every parts house sells a copy of the 1931 edition.

Re: Thread size on the distributor shaft to tighten the cam screw?
 

Yep, I was wrong. Serves me right for going out in the cold garage and just guessing. My 1929 Parts Price List says .325-30. You are right, weird.:)

Re: Thread size on the distributor shaft to tighten the cam screw?
 

That sounds suspiciously like 8 mm X 1.25 25 mms per inch = .040 x 8= .320 (plus .005 for the oversize ground on all taps) = .325 X 1.25.
Who knows what mysteries lurked in the mind of Henry Ford? Anybody who would use #12 X 24s has to be a little nuts.
Terry

Re: Thread size on the distributor shaft to tighten the cam screw?
 

I guess the fine thread, .325-30 is to insure a tight lock of the cam.

Distributor Cam Screw And Washer
Code:A12211/13
Price: $1.25
Model Year: 1928 - 1931
UOM: Set
Quantity in Basket: none
"This Special screw with washer holds the cam to the shaft. Now has an oil hole, especially made for A12178M, but no problem being used on original upper shaft."

Re: Thread size on the distributor shaft to tighten the cam screw?
 

It's not 8x1.25, I have one of those taps and it didn't even go in half a turn. Plus I think you've gone the wrong way with your thread calculation. Thirty tpi or .0333" per thread pitch is .83mm, ie .0333" divide by .040"(1mm). So it's not metric.

Re: Thread size on the distributor shaft to tighten the cam screw?
 

Hmmm. Metric threads are a mystery to me. Lessee, 1 mm = .040, 1' = 25mm. or 25 threads per in. (1.00mm pitch) 30 TPI=..., ahh crap! It either fits or it don't and it don't! It sounded good for a while while! Whereinhell did Henry dig that one up. It isn't even a 1/32 size, 11/32 =.343. Reminds me of a lathe headstock I have 1 1/16 X 16 spindle nose thread. Cheers! Terry