Packard Forum Index » General

Hello all, is there a simple safe way for me to test a starter switch? Picked up one from an auto wrecker for $15. I will be getting a key cut for it.
Power to battery feed, test light or OHM meter??
thanks in advance for your help

Attach file:

---

  Ignition switch-ipull-upull (1).JPG (138.11 KB)

Power to BAT and use a volt meter between batttery ground and the other terminals. Key off, no other terminals hot. Key to left, only ACC hot. Key to right both ACC and IGN hot. Key to start and only IGN and STRT hot. Make sure the switch feels and moves smoothly between all positions and there is a good solid voltage at each position. Also make sure slightly moving, bumping or wiggling the key and switch does not make the reading start being erratic. You can also use an ohmmeter between BAT and the other terminals. In the same positions you should read a dead short going between the same terminals or at most a couple of ohms instead of a voltage. At any position, if you get a resistance reading of more than a couple of ohms suspect the switch might have a bad internal connection to a terminal. Same test with wiggling the key. Even the best of static tests will not be able to find a connection issue that only becomes apparent because of something in the switch heating up.

The issue with the switches mostly begins with the start contact. The large pinion shift solenoids used on senior models pull a lot of current which stresses the rather small start terminal in the switch to the point it pits and becomes rough or even melts. Once either happens the moving contact plate it and the other contacts rely on wants to stick or not move between positions. In that instance often the spring cannot return the moving contact to the run position when you let go of the key after the engine starts and starter hangs on and keeps running. The other issue with the switches is Packard started adding more of the heavier current needing accessories and the ACC contact started becoming overloaded. Overloading heats and warps the plastic contact support which brings up other issues and eventually the switch does not make reliable contact. That is often noticed when the key starts needing to be jiggled for the switch to work.

Here are a couple of photos showing the melted start contact and contact plate along with the active switch combinations.

Attach file:

---

  terminals.jpg (67.55 KB)


  ign sw copy.jpg (176.77 KB)

Nice find! The bezel appears to be the Clipper type but will be more obvious once cleaned up. If Clipper, it will be shiny chrome but if Packard the area with the lettering will be brushed.

Thank you very much HH56 for the very helpful reply. Here’s hoping I got lucky

Don, you are correct. They are putting up for salvage a 56 clipper super sedan. It was pretty much picked over by the time I got there. Still a few usable bits left if I can get back

Will add it to the registry hopefully. The vin plate has been removed but the block is in the trunk. Maybe I can get the vin no. Off of it

UPDATE: wow didn't know key cutting was so expensive these days. Anyways, tested the switch as per HH56 instructions. It works! so I have a spare