Rear wheel cylinder - what thread are the 'tube nuts'?

[Paul Y]

Evening all,

Quick sanity check as I want to get the brake system buttoned up on old Woody before the weekend and need to order parts.

What thread are the rear wheel cyclin dress on a 66 C10?

Found a few contradictory answers on the web so thought I would ask here as I trust your opinions a lot more than NoobMaster69...

So, do I need to order for my 3/16" line, tube nut with 9/16-18, 1/2-20, 7/16-24, or 3/8-24 thread?

I 'think' I need 7/16-24 but would appreciate confirmation.

Thanks in advance.

P.

[PGSigns]

They are 3/8 16.
Jimmy

[Paul Y]

Thank you Mr Signs.

Trying to find those in the UK is proving to be a ...challenge... Did find the old ones but they are 55 years old and don'r really want to reuse them unless I absolutely cannot avoid it.

P.

[car10107]

The threads mentioned above didn't sound right to me so I used a couple taps to verify for you and anyone else that might need the specs in the future.

The threads for the bolts that attach the wheel cylinder to the backing plate are 5/16" X 18tpi.

The inverted flare thread specs for the 3/16" hard line fitting is 3/8" x 24tpi.

I don't know if you have access to Amazon across the pond but when I redid the rear brake lines on my 65, I bought this kit for $24. It comes with 25' of 3/16" copper/nickel line and an assortment of inverted flare fittings including (10) of the 3/8X24 fittings you need. The copper/nickel line is extremely easy to bend and to flare. I will never use steel line again.

https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

[Paul Y]

Thank you for the double check Mr. Car.

I 'thought' I had ordered 3/8 - 16 but what arrived this morning was 3/8 -24.

So, I will do what I should have done a few days ago and go and measure what I have!

100% with you on the Cunifer brake line - been using to for the past 30 years+ and it is really easy to work with and doesn't rust.

Amazon has a fairly strong foothold in the UK, I can order products at 10am and have them here before 5pm in most cases. Not sure if this is a good thing or not for the venerable High Street but only time will tell.

Appreciate you taking the time to measure your wheel cylinders.

P.

[Paul Y]

Can confirm, rear wheel cylinders on a 66 C10 use a 3/8 24 unf short tube nut.

P.