D Murton Posted August 31, 2017 Report Share Posted August 31, 2017 Before last years MOT I had to replace the dip switch on the 4a. On Sunday I gave the car a good check to make sure everything was OK for this years M.OT. Turned up at the testing station today to find the dip switch only working intermittently. Luckily with a sympathetic MOT man & a bit of fiddling I got a pass. I know this has been discussed before but all the usual suspects seem to be selling the same switch. Has anyone got any idea of where I can get one that lasts more than 12 months? Dave Quote Link to post Share on other sites
RogerH Posted September 1, 2017 Report Share Posted September 1, 2017 Hi Dave, I had exactly the same problem. Back in July my 4A dip switch that is 50 years old decided to embarrass me. Eventually it worked enough for the MOT man to give me a pass and tell me to go away. I bought a new switch from one of the big suppliers and firstly tried it by hand - it worked ---------- then it didn't, then it did. It continued like this until I gave up. This cost over £10. I went to Ebay and bought the cheapest new switch I could find - it ;looked identical in every way to the previous new one. I tried it by hand - it was worse. Very very stiff and after after about two toggles it seized. So I took the original 50 year old one to pieces. This is a bit fiddly but the cap does come off. What I found was that the cap was mishaped and sticking on the body. After a couple of minutes reshaping the cap and a little filing to remove high spots on the body it worked beautifully. So that was refitted and a treat to use. I went back to the first replacement and decided to operate it by standing on it - it worked every time. Quite heavy operation but it works. The Ebay cheapo had the same done to it but this was made of sterner stuff and refused to move Most 50's, 60's, and 70's cars had these fitted - you would think it would be easy to reproduce them but alas no. Roger Quote Link to post Share on other sites
D Murton Posted September 1, 2017 Author Report Share Posted September 1, 2017 Hi Roger You would think it would be easy to reproduce wouldn't you. When I got home I took out the offending item. It appeared to work OK most of the time but the plastic switch block is held into the metal body by staking on each side. This seemed to have been done by a visually impaired work experience person & so it was quite loose. Not wanting to risk breaking the switch by trying to tighten the staking & wanting to use the car while trying to source a proper replacement I resorted to sliding a thin strip of plastic between the switch block & body & retaining it with a blob neat bead of JB Weld. Now works perfectly every time. I didn't spend 40+ years in engineering for nothing. Browsing the web it looks as if everybody sells the same item although the one shown on the Racestorations site looks as if it has two additional rivets going into the switch block. Must investigate further. Dave Quote Link to post Share on other sites
Andy Moltu Posted September 1, 2017 Report Share Posted September 1, 2017 Or get a couple of diodes and a latching relay and use the flash element of the switch as a dipswitch. Quote Link to post Share on other sites
D Murton Posted September 1, 2017 Author Report Share Posted September 1, 2017 Andy I had been thinking along those lines but was going to use the overdrive switch as I have the OD switch in the gear stick. Why would I need the diodes? Thanks Dave Quote Link to post Share on other sites
tthomson Posted September 2, 2017 Report Share Posted September 2, 2017 Hi Dave, I have modified my TR4A to use an O/D switch as a dip switch. It requires two relays and no diodes, but works well. I can send a copy of the wiring if you PM me with an email address. I still have lighting stalk with flash. I still have my O/D switch on RHS of column, but added a new additional O/D switch on LHS of column as dip switch. it needed a new escutcheon, but was relatively easy to fit. TT Quote Link to post Share on other sites
TorontoTim Posted September 2, 2017 Report Share Posted September 2, 2017 Roger et al - have you done similar testing on the early version (round base)? Are the current offerings just as crap? Or do they mount differently anyway, so are no good for the later application? Quote Link to post Share on other sites
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