8port Heater valve stud thread size?

[Mark1Peachey]

Anyone happen to know what the thread tapped in the Minispares Arden 8port head for the heater valve studs are? Just gone to fit the two studs and the thread isn't the standard 1/4 UNF. I thought it might be 1/4 UNC as with it being alloy but that didn't seem to match either.

Any help would be great.

Many thanks,

Mark

[Stopped-again]

If it’s neither unf or unc, I know it’s not period but it’s most likely to be 6mm, highly unlikely they’d use anything else.

[Mark1Peachey]

Thanks for your reply. I’ll have to dig out some metric stuff tomorrow and give that a try.

Regards,

Mark.

[Oneball]

The mini spares catalogue lists the replacement as the standard item.

[Mark1Peachey]

That’s what’s so confusing I went to put the standard item in and it wasn’t going to go. The thread is nice and clean. Tried running a unf tap down in case the start of the thread was burred over but just didn’t feel right. Tried an M6 tap today but again not the one. Got a M6 course tap on its way in the post to try that.

Might need to get another set of eyes on it if that fails. I’m sure I’m missing something very obvious.

[Stopped-again]

Or try an email to Minispares North, Rich’ll know and if not he’ll find out for you.

[Mark1Peachey]

Just for reference more than anything the thread in the 8port was 1/4 UNC. Turns out I needed to be more brave I cleaned out the threads with a UNC tap then turned down some stainless and made up some studs. I left the shoulders a big bigger to suit the heater valve. Although the overall length is the same as the ones I brought they appear a little proud when the heater is fitted. Might need a thicker washer or taking down a little more.

Thanks for the replies and advise.

Regards,

Mark.