So I snapped the stud in my float chamber

Hi all

I was disassembling a set of HD8 carbs and one of the studs snapped off in the bottom of the float chamber. :confused: (The long vertical stud that the float goes around. )

This looks like it’s not repairable but thought I would ask if anyone has dealt with this before.

Anybody have an idea, or maybe a spare float chamber?

If you need to replace it I’d suggest Joe Curto

Before you give up on it, perhaps you could post a photo of it here. There are a number of ways of removing broken studs depending on the exact nature of the problem. Some good videos on YouTube of different techniques that could apply…

Call Curto and ask if any other HD8 carbs use the same bowl (in the event yours is unsalvagable). A bowl without E-Type in the description will cost less.

The bowls on my Rover are identical.

I think the stud is cast in.

If it’s of any help, the SU part number for the float chamber is AUC 2009.

The same float chamber is fitted to the rear HD6 on the Mk2 Jag and probably other saloons fitted with HD6’s or HD8’s.
On the Mk2 (and probably the other saloons) the front carb has a different float chamber as it has an electric choke fitted and has a banjo bolt fitting at the bottom.
It probably could be plugged if desperate.

Paul

All of the float chambers from the various HD8 carb configurations will work though some will require a plug at the bottom where it attaches to the throttle body. In your place I’d drill out the stud from the bottom and replace it with a correct length of 1/4" rod stock threaded UNF 24 tpi set in place with Devcon 10610 aluminum putty … though JB Weld would probably work as well.

Be aware that the upper threaded end is not 1/4-28 but a witworth thread. I know this because I just replaced the rod on a carb. My solution was to make a new top nut in my lathe that is 1/4-28 as I have that die. Parts are not interchangable, but I don’t care. I used retaining compound to seal the bottom of the float bowl threads as it was a through hole. I use retaining compound in lots of places, it’s great stuff.

Right. 26 tpi.

Good catch.

If it’s 26tpi, then it’s 1/4" BSF. 1/4" BSW is 20tpi. BSF(fine) and BSW (coarse) have the same 55 degree thread form.

1 Like

Humbled again.

I plead thread standards derangement syndrome - TSDS. I’m currently restoring a 1954 XK120 that features five different fastener standards (BA, BSF, BSW, BSP and SAE) and haven’t quite got it all sorted out.

Sorry about the delayed response. That work thing can really get in the way sometimes. Here’s a couple of photos. Obviously water was sitting in the bottom… there’s maybe an 1/8” stub on the bottom.

And the broken stud. Not surprised it snapped as there not much left

1 Like

Wow! With that much corrosion in the bowl, what does the rest of the carb look like?

1 Like

They rust there, and (on the hisser carbs as used in the Saloons) at the banjo which holds the hisser feed, float bowl, and bottom of the jet diaphram chamber together.