This is why I dread making brake & clutch hoses – it’s not the making (which I like), it’s working out what connector sizes….

For background, I bought the 2 metal pipes/1 rubber hose the part book lists to connect the clutch master to the slave. The third pipe I managed to bend to fit, but then I discovered it was not keen on screwing into the slave. So, I reverted back to the original i had taken off the vehicle, which screwed nicely into the slave, and connected fine to the rubber hose.

The issue is at the master: the new metal pipe connects to the rubber hose fine, but it is not keen on screwing into the master.

I think it is 20 threads-per-inch on the new pipe, but I can’t really work out what TPI the master is.

When I measure diameters:

• The master is about 9.75mm internally across from the peak of the threads.
• The connector on the pipe is about 10.3mm across from valley of thread.

So, I am pretty sure these don’t fit.

Unfortunately, I can’t track down my original pipe – I am pretty sure it got trashed when I removed it, as it was so corroded.

I am happy to make a new pipe, but the issue is I don’t know what size connector I need to buy.
Photo is of the new pipe, and the connector that fits on the master.

Can you not fit the old connectors to the new pipe before you flare it?

The smaller thread going in to the M/Cyl is 3/8 UNF (nut hex is 7/16 spanner)
The larger thread of the steel adapter is 7/16 UNF (nut hex 1/2 inch spanner).

On a side note, if you drill out the hole in the centre of the steel adapter by 2mm it makes the clutch pedal noticeably lighter. Just take care tightening it into the master cylinder. New adapters can be found from Britpart for a few quid.

Interesting. I will see how the clutch feels and will consider what you suggest.