AboutJo Jesty Expertise Most detailed about Austin Healeys but also MGs (A,B,C), old Minis, old Volvos: they share SU carbs, Lucas (Prince of Darkness!) ignition, Girling brakes & shocks. Some things shared with TRs too, but I don't know so much about them. Can advise the semi-neophyte on the basics of keeping things running, especially tuning ignition and carbs: but no rebuilding engines or transmissions; no frame or bodywork.
Experience Middling: I am not an auto mechanic. (Should we stop right here?)
Grew up In England and a workshop. I have had a 3-carb 60/61 Healey for ca. 8 years, largely looked after myself. New fuel system and carbs and resuscitated ignition recently. Brakes always fine. Great driver's car. Major jobs done by others: king pins, front frame cancer excision; caliper rebuild; etc. Organizations.: Austin Healey Sports & Touring Car Club (PA)
Publications: irrelevant
Education/CredentialsPhD: irrelevant to this
Awards and Honors: irrelevant
Languages: I could try French...
Expert: Jo Jesty Date: 3/17/2008 Subject: Positive Ground
Question What is the easiest way to determine whether my newly acquired Triumph TR3 is set up for positive or negative ground? It was originally positive (British)but the generator was rebuilt and there is no battery in the car.
Answer It's likely still positive. (1) The ignition switch wire should go the negative terminal on the coil. (2)Battery terminal posts and connectors are slightly different sizes. My car is not close by to check, but I think the negative is the larger post (check your own regular car). If it's positive ground the ground strap (to the frame) will only properly fit the positive post. And vice versa.
Unfortunately you can't check the generator output until the car is running (which needs the battery!). But there's a nice wiring diagram at http://www.advanceautowire.com/tr24a.pdf complete with generator wire colors and voltage regulator terminal letters. That's for positive ground.
