5 replies to this topic

[MatthewsDad]

Hi please could someone confirm the thread type / size on the pipe side of the boss that fits into the block i.e. not the thread that goes into the block, which I appreciate is covered in other threads? It's a 1968 998 cooper. Thanks

[nicklouse]

It’s a banjo bolt into the block.  An image of what you are looking at will help as thst is the only fitting to the block. It changed in the early 90s.

[Ethel]

As above. If it's been adapted for an oil cooler etc it's probably 1/2 bsp, but that's just a guess. It's still a common thread size, if you have a garden tap you may well have a 1/2 bsp connector.

[imack]

I'm guessing you're talking about the thread on the adaptor with the red cap in the block for the oil pressure gauge pipe?

Attached Files

•  Screenshot_20260316_124017_Gallery.jpg   32K   3 downloads

Edited by imack, 16 March 2026 - 12:45 PM.

[Ethel]

Yellow is 5/8 unf. Red is 1/8 BSP (1/8 nptf in to the block)

[MatthewsDad]

Thanks everyone for your help. It's the red cap thread above. Really helpful.