T236 engine - Trouble with the connection between crankshaft and flywheel

[T236-Dose]

Hello everybody, my T236-engine for my Candian Dodge is nearly ready. But as always on the last mile unknown problems are popping up. Here is my one: Usually there are 8 studs at the rear end of the crankshaft to fix the flywheel. The part number of the studs is CC871685 (7/16-20 with a special head). They are always the same, in the 23-inch-engine as well as in the 25"-engine and they are mounted with a kind of clamp connection - I hope that is the right word.

So I bought  a set of 8, because that barn find engine I'm reconstituting they where missing. But my holes are bigger! The diameter is somewhere between 7/16" [11,11mm] and 1/2" [12,7 mm] - or in our European measurement around 11,8 mm.

Is that a common mistake after so many years? I could use self made studs and fix them on the engine side with a nut. But to cut 8 holes in the crankshaft with a 1/2 thread seems to be too big, I could cut a 12 mm thread with a thread pitch like UNF.

Does anybody has a better solution?

 

And an additional hint for other enthusiasts: The NOS "flathead oil pans"  for the 237/251 engines which are sold for 95 $ from Vintage Power Wagons don't fit on the T236 engine. The length is okay, but in the area where the oil strainer assembly is, they are too narrow. I bought one, it was shipped half around the world, sandblasted, carefully painted and now I can't use it. **** happens.

 

Regards

 

Jürgen

 

 

 

[Sniper]

11.8 mm works out to be 0.464" which falls between the normal and close fit specifications for the hole a 7/16" bolt will fit thru.  Id say you are ok with the hole and the bolts you have.  By the way, the fastener you show is called a bolt not a stud in English.  A stud would have threads on both ends, a bolt has a head on one end and threads on the other. 

 

Bolt hole sizing chart

 

https://amesweb.info/Screws/Clearance-Hole-Chart.aspx

 

Edited December 17, 2020 by Sniper

[T236-Dose]

Hello Sniper, thanks for answering and of course you are right - if I would be able to read what is written on the old original box I should have noticed that myself ?

[Sniper]

17 minutes ago, T236-Dose said:

Hello Sniper, thanks for answering and of course you are right - if I would be able to read what is written on the old original box I should have noticed that myself ?

It's all right, your English is much better than my German.  I did study German in high school, sort of like your Gymnasium, but that was a very long time ago.

[Young Ed]

I can see how you'd call it a stud as it's similar to a wheel stud. I believe the engines with bigger holes used standard nuts and bolts for flywheel installation. I believe the great don c used shoulder bolts in his swap