Sun Electric Automotive Test Equipment

To go with the old British cars, I've been buying a few Sun Electric testers sold during the same period - late 50's through the 60s.


The funny looking screws that hold the front panel to the instrument case are called clutch screws. At least that's what some former Sun technicians I know called them. Tru-Value Hardware sells a screwdriver for these screws, the markings on mine state "Master Mechanic 367169 USA CL532".


I've been looking for a source for the blue hammer-tone paint. I've bought a gallon of Sherwin-Williams Dimenso Dark Blue Enamel, but haven't tried it yet. The product code is 522-2302 and the Dimenso paint is described in product info sheet CC-B5. The paint seems to be available in only the gallon size and has a shelf life (unopened) of two years. So be sure to have the the sales person check the date code on the lid before you buy it.

Mercury Batteries

My distributor tester and the dwell meter use to use mercury batteries. The mercury battery had one very nice characteristic - the supplied voltage was constant until the battery was almost completely discharged. The voltage from current batteries tapers off as the battery discharges.

The AA mercury battery was Sun part number 1766-7 and was made by Mallory, part number RM12R.

For the distributor tester, I've installed a power supply to replace the 1.35 volt battery. I bought a variable DC voltage power supply kit from a local supplier. The kit (PN 68) was $13 and is also availabe from the manufacturer's web site. The kit runs off either an AC or DC input. For the distributor tester, I used line voltage through a transformer for the input voltage. I may have changed one of the resistors to drop the output voltage range.

I haven't decided what to do for the dwell meter yet. It's portable, so I'd hate to add a line cord.