Barrel Studs

[Ken.Wallington]

I need to add another barrel stud to my engine casing, the engine number is CJ. Can someone please tell me diameter and thread I need to tap to use a standard stud?

Thanks in advance

[john.nash]

It might be a cheeky way to do it, but Draganfly http://www.draganfly.co.uk/ list all the parts, often with helpful exploded diagrams.

For example here is that picture again of your crankcase and fittings:

and here is the Draganfly parts page:
http://www.draganfly.co.uk/shop/pi17996 ... egoryId=82

Now the useful bit is that they have two pages that list, between them the sizes and threads of all the fasteners,. Here is the stud one:
http://www.draganfly.co.uk/shop/pi11546 ... goryId=141

Simply find your part (i.e. 0280 is the stud for the iron NH), which is listed as 0280 3/8 dia 1 9/16 long with CEI/Whit thread (i.e. it has two different thread types at each end).

simples

[Ken.Wallington]

Not cheeky at all in fact I use the DraganFly site a lot now, thanks to your heads up.

I couldn't however find the thread size as I need to add an extra stud.

[brenton.roy]

** Ken, CJ is a '48 cast iron square four?

If so, I think you need a 5/16" whitworth tap.
All the pushrod squares had the same studs (I don't know about cammies).
(5/16 - 18TPI - Tap with Letter Drill F (6.5 mm)
Here's the info; (this is part one of a 3 part article)
http://www.barkshire.co.uk/AOMCC/Knowle ... spx?id=187

Please wait until someone else writes in to verify before you drill - or get out the verniers, measure an inch and count the threads. I'm not keen on pulling out a stud to check! Hopefully, you've got one to look at?
Have you had it welded or used a plug?

Brenton

[nevhunter]

The singles have 3/8 dia studs and the 350's are shorter than the (later) 500s. The threads are 3/8 whit in the aluminium and 3/8 (cycle) x 26 tpi for the end that takes the nut. You say you want to put in an extra stud. Is that for the later barrell with the cast in pushrod tubes? I am not sure whether the 5th stud is 5/16 th dia or 3/8. You would have to check in the barrel flange for the dia. The VCH's are all 3/8 dia. (6 stud). Nev

[Ken.Wallington]

Thanks all, sorted now. Got a gasket today to use as a template, need to check this again and again before I start drilling. Thanks for bearing with me.