LarrBeard
05-21-2015, 08:43 PM
The ignition switch had problems. It gritted and ground as the key was turned and stuck between positions too. I took the switch to the local lock shop and the locksmith did a great job in cleaning up the tumblers in the cylinder. But - he wouldn't touch the switch end. It is secured with four pressed down tabs that in all probability will fracture if you try to loosen them. I don't blame the locksmith for not wanting to fool with it.
I took the switch home and gave the switch end a good looking over. It has the standard three terminals; a threaded stud that ties to the battery, a screw lug that is what would be called the Accessory (ACC) terminal, and the third terminal as the Ignition (IGN) terminal. A check with the meter gave some weird results. BATT to ACC was a pretty good contact - but intermittent. BATT to IGN was no good - 10 to 25 ohms, way too high. But - the kicker was that in the OFF position, there could be as low as 5 ohms between terminals. That's not good - the switch is never off.
There were three options; find a replacement from a parts truck that might have worse problems, use an after market universal switch that really didn't fit - or open it up and try to fix it. What the heck - it's already broken - let's try door number three!
I soaked it in mineral spirits and swashed it around as much as I could - not much change. It had to come apart. I pried on the ears that secured the switch to the lock body as carefully as I could - but one ear broke off. Aw Pooh! Anyhow, the switch end came off; some plastic pieces, a brass terminal contact and a spring. BUT - the switch end was loaded with graphite after 60-plus years of locksmiths and garage mechanics squirting graphite grease into the switch. Graphite is powdered carbon - it's an electrical conductor! No wonder it wouldn't turn off!
I cleaned out the grease, buffed the contacts and cleaned them with a cleaner called DeOxit. By holding the switch together with my fingers, I was able to verify that things had improved a lot. Now - how to get it back together?
I ended up using a C-clamp as a holding fixture and JB Weld Steel epoxy to hold the plastic switch assembly to the metal body. It set up and I checked out the switch. BATT to ACC measures in the milli-ohm range, BATT to IGN measures about a half-ohm. I expected this since the terminals were oxidized a bit. Shouldn't be a problem - if needed we can tie ACC and IGN together.
I'm pleased how it turned out. In four or five years we'll know how well the JB Weld holds.
I took the switch home and gave the switch end a good looking over. It has the standard three terminals; a threaded stud that ties to the battery, a screw lug that is what would be called the Accessory (ACC) terminal, and the third terminal as the Ignition (IGN) terminal. A check with the meter gave some weird results. BATT to ACC was a pretty good contact - but intermittent. BATT to IGN was no good - 10 to 25 ohms, way too high. But - the kicker was that in the OFF position, there could be as low as 5 ohms between terminals. That's not good - the switch is never off.
There were three options; find a replacement from a parts truck that might have worse problems, use an after market universal switch that really didn't fit - or open it up and try to fix it. What the heck - it's already broken - let's try door number three!
I soaked it in mineral spirits and swashed it around as much as I could - not much change. It had to come apart. I pried on the ears that secured the switch to the lock body as carefully as I could - but one ear broke off. Aw Pooh! Anyhow, the switch end came off; some plastic pieces, a brass terminal contact and a spring. BUT - the switch end was loaded with graphite after 60-plus years of locksmiths and garage mechanics squirting graphite grease into the switch. Graphite is powdered carbon - it's an electrical conductor! No wonder it wouldn't turn off!
I cleaned out the grease, buffed the contacts and cleaned them with a cleaner called DeOxit. By holding the switch together with my fingers, I was able to verify that things had improved a lot. Now - how to get it back together?
I ended up using a C-clamp as a holding fixture and JB Weld Steel epoxy to hold the plastic switch assembly to the metal body. It set up and I checked out the switch. BATT to ACC measures in the milli-ohm range, BATT to IGN measures about a half-ohm. I expected this since the terminals were oxidized a bit. Shouldn't be a problem - if needed we can tie ACC and IGN together.
I'm pleased how it turned out. In four or five years we'll know how well the JB Weld holds.