jogger321 Posted July 31, 2018 Report Share Posted July 31, 2018 I've just purchased an oil pressure switch for my 71 TR6...Single electrical connector type....It appears to be the wrong thread ...Its ok I have not damaged the thread as it was obvious the one I got was bigger...although the manufacturers website suggests its correct for a TR6 ...Does anybody know if different thread types were used according to the year of manufacture? Quote Link to post Share on other sites
RogerH Posted August 1, 2018 Report Share Posted August 1, 2018 Moss suggest that they should all be the same #97 https://www.moss-europe.co.uk/shop-by-model/triumph/tr5-6/electrical-system/gauges-instruments/switches-relays-fuses-tr5-6.html Roger Quote Link to post Share on other sites
colin3511 Posted August 1, 2018 Report Share Posted August 1, 2018 Double check. I changed mine recently and thought it was wrong but it was correct. NPT thread. Quote Link to post Share on other sites
jogger321 Posted August 1, 2018 Author Report Share Posted August 1, 2018 I'm going to take another look later today...maybe my eyes were deceiving me ...I was keen to take it for a drive yesterday evening so put the old one back in... This is the item I have and it looks to me like its the correct one although the one in it currently doesnt have the large nut to undo it https://hc-cargo.co.uk/catalog/p/180649--70027-oil-pressure-switch Quote Link to post Share on other sites
jogger321 Posted August 2, 2018 Author Report Share Posted August 2, 2018 I thought I would report back I took the old one out again and tried to put the replacement in. Initially I had the same problem and it appeared visually to me (a complete amateur) that the threads were different and the old one more tapered...I then looked more closely and this appeared to be an optical illusion created by the old one having half the thread dirty with oil.. I'm always concerned about stripping threads ever since I stripped a spark plug thread on my moped when I was 16 and turned the plug with a socket as tight as I could get it...With the result that I learned what a"helicoil" meant and also learned about removing cylinder heads was about :-) Anyway back to my TR6 So I had another go at putting it in after ringing one of the TR specialists who confirmed that only one thread type was used in production Slowly, by hand and eventually I got it to bite...3 turns, am I cross threaded ??? No remove and do again just to make sure :-) Final time, yes its lined up and turning in and looking straight...Few more turns then nip up with an open spanner...Not too tight because if it has a slight drip it can be nipped up a bit more...far better than a stripped thread in the block down there!!! Anyway job done, sigh of relief ...Its not leaking ....and whats even better I took it for a long run afterwards and the oil light is staying off when the oil is very hot at low revs and the pressure guage is telling me everything is good! Quote Link to post Share on other sites
Kevo_6 Posted August 2, 2018 Report Share Posted August 2, 2018 I thought I would report back I took the old one out again and tried to put the replacement in. Initially I had the same problem and it appeared visually to me (a complete amateur) that the threads were different and the old one more tapered...I then looked more closely and this appeared to be an optical illusion created by the old one having half the thread dirty with oil.. I'm always concerned about stripping threads ever since I stripped a spark plug thread on my moped when I was 16 and turned the plug with a socket as tight as I could get it...With the result that I learned what a"helicoil" meant and also learned about removing cylinder heads was about :-) Anyway back to my TR6 So I had another go at putting it in after ringing one of the TR specialists who confirmed that only one thread type was used in production Slowly, by hand and eventually I got it to bite...3 turns, am I cross threaded ??? No remove and do again just to make sure :-) Final time, yes its lined up and turning in and looking straight...Few more turns then nip up with an open spanner...Not too tight because if it has a slight drip it can be nipped up a bit more...far better than a stripped thread in the block down there!!! Anyway job done, sigh of relief ...Its not leaking ....and whats even better I took it for a long run afterwards and the oil light is staying off when the oil is very hot at low revs and the pressure guage is telling me everything is good! oil pressure switch.jpgoilpressureswitch2.jpg Hi Jogger Well done for your perseverance, if your not sure it’s always good to take the cautious approach as you did. I don’t know if it’s an optical illusion but your oil pressure gauge pipe looks kinked and you don’t want that to let go when you are motoring along. Mine is very similar and I have new pipe to replace it with, bit of a bu$$er of a job. Quote Link to post Share on other sites
TR NIALL Posted August 2, 2018 Report Share Posted August 2, 2018 Your old Switch looks to be a Tapered Thread and the New one isn’t or is it my Eye Sight. Quote Link to post Share on other sites
Gary Flinn Posted August 2, 2018 Report Share Posted August 2, 2018 Ensuring a gas or liquid-tight connection means understandingtapered pipe threads. NPT, National Pipe Taper (American) and BSPT (British standard Pipe Taper) are tapered pipe threadstandards. Male and female tapered pipe threads wedge themselves together but need a sealant for a completely leak-free connection. Tapered Pipe Threads and Fittings: Making the Connection | ISM ... https://www.industrialspec.com/about-us/blog/.../tapered-pipe-threads-standards-intro Quote Link to post Share on other sites
Waldi Posted August 2, 2018 Report Share Posted August 2, 2018 Your old Switch looks to be a Tapered Thread and the New one isnt or is it my Eye Sight. Good you resolved it yourselves:) +1 for the Question on tapered or not. Also, the number of threads engaged appears to be minimal. It should be 5 or so, so approx 5 full turns when finally tightened. If hit hard, it may now come out. Maybe there is some ols sealant in the bore that prevents the new switch from being further turned in? You can use thin ptfe tape (there are different thicknesses) or a pipe sealant to ensure it will not leak. Keep on practicing, thats what we all do. Waldi Quote Link to post Share on other sites
jogger321 Posted August 2, 2018 Author Report Share Posted August 2, 2018 Thanks guys...You can see why I thought it was the wrong one when I first tried to fit it....I think its an optical illusion and it is tapered The switch came out of a box that tallys with the manufacturers web site and the spec is Thread size 1/8-27 NPT cone I will keep an eye on it for leaks and if necessary put some ptfe on if required 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.