Hello to all. I have a March 1935 Ruby fitted with a Dk distributor all the while I have had it the small bolt that fits from the block into the groove on the outside of the dizzy has been missing and the car has run well just relying on the clamp to keep it in place. However recently on retiming the engine with the clamp bolt loose I found that I could not turn it clockwise far before there was no more adjustment. After some head scratching I lifted the dizzy slightly and found I could adjust everything ok. I also realised the purpose of the bolt that goes into the groove on the body of the dizzy.
Can anyone tell me the size and thread of this bolt.
John Mason.
Would you believe it "Her who must be obeyed" refers to my Ruby as the toy.
Thanks to everybody. I will try 1/4 BSF to start with as I have one of those and will file the end to match the photo.. if it is 6mm it will have to wait until I get one.
Davis I assume the dog point is the bit without threads on that locates into the groove.
Once again thanks to all.
John Mason.
Would you believe it "Her who must be obeyed" refers to my Ruby as the toy.
The thread measures either 26 tpi or 1.0mm depending which thread gauge I use. The o/d of the thread is .234", which is 2 thou less than 6mm, but a way off .250". A 1/4" bsf stud will not go into the female, so my thread must be M6 and not 1/4" bsf.
Apologies. It never entered my head that a Seven might have a metric thread as standard. I had assumed an imperial fitting and made the short cut from 26 tpi to 1/4" bsf.
Just shows that the only way to be sure is to test fit a known item.
0 BA is 6mm and the same pitch as M6. For short lengths it can be tapped out for 1/4 BSF.Similelrly for short lengths ragged 1/4 BSF male threads can be reduced to M6.
