ronhatch Posted May 14, 2022 Report Share Posted May 14, 2022 Hi all , can anyone tell me what are the sizes of the reducer between the heater spigot on the TR4 head and the heater valve or the part number, I can only see the long one in the catalogues. Regards Ron Quote Link to post Share on other sites
Grahamgl Posted May 15, 2022 Report Share Posted May 15, 2022 (edited) Hi Ron, On both my 4 and 4A the heater valve screws directly into the black iron 45 degree bend which is screwed into the cylinder head. No idea what the thread form is though. Graham Edited May 15, 2022 by Grahamgl Quote Link to post Share on other sites
ronhatch Posted May 15, 2022 Author Report Share Posted May 15, 2022 Hi Graham, Thanks for the reply. The iron bend on my head has a smaller diameter thread than the heater control valve, the original head has a reducer from the valve to the iron bend but I couldn't use that head, the one I used has the iron bend but no reducer, I am loathe to swap them in case they shear and cause more problems as the head is now attached. My other TR4 has the iron bend with the correct thread to take the valve, it may be an earlier version but the thread is smaller, can anybody enlighten me ? Regards Ron Quote Link to post Share on other sites
RogerH Posted May 15, 2022 Report Share Posted May 15, 2022 Hi Ron, I'm sure that the 135' black iron elbow is 1/4" BSP male x 3/8" BSP female. Roger Quote Link to post Share on other sites
ronhatch Posted May 15, 2022 Author Report Share Posted May 15, 2022 Thanks for the reply Rodger, did triumph fit a smaller size of iron fitting as I have 2 heads with different size irons and a 3rd one ( the original one) with the smaller iron fitting and an adapter/reducer to suit the valve, curious but not the first time with triumph Regards Ron Quote Link to post Share on other sites
RogerH Posted May 15, 2022 Report Share Posted May 15, 2022 Hi Ron, I think there is only one size but I could easily be off with the fairies. The genuine part is very expensive for what it is (£10) so it would be easy to fit all sorts to get it to work for pennies. Roger Quote Link to post Share on other sites
Bfg Posted May 15, 2022 Report Share Posted May 15, 2022 I don't know if it's pertinent to your needs, but because I felt the bent bit of Victorian plumbing looked like.. well tbh.. a bent bit of Victorian plumbing - I left it off. The old heater control valve had rusted away and so, on the recommendation of contributors to this forum, I ordered one from the US. And as that screwed straight in to the block, we might only presume the bent bit of plumbing has the same size and pitch of female thread as this TR4 cylinder head. Pete p.s. in fitting this new control valve - I was obliged to ease it (bend it up a touch) over the cylinder head stud. With the valve being of pressed-steel construction, it took to the bending quite easily and without detriment. Quote Link to post Share on other sites
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.