The ignition key in my '64 544 does not turn most of the time, I have to fiddle with it ... a LOT!

Is it the switch, the cable to the ignition coil, or the coil itself

For a worn key, is it steel or brass? A brass key may be well worn by now.

Does pulling it out a hair while turning allow it to work better? Does lifting it while turning make it work better?

I recall yours uses a separate ignition key, but if not then any trouble using it in the other locks? Do you have a spare key? Does it work any better? Compare the keys for wear with the backs flat to a surface.

Do you have more than 2 or 3 keys on the key ring, garage door opener, metal fob, church key, etc.? A heavy key chain hastens wear of both the key and the keyway (as I learned the hard way).
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Dave -still with 940's, prev 740/240/140/120 You'd think I'd have learned by now

Guys - Thanks for the input.

DOH - If I have luck jiggling the key, I guess that the switch is a good place to start.

Assuming you have the stock ignition switch assembly, if you have to jiggle the key to get it to turn, the problem lies with the key or the tumbler assembly and not the switch.

As I said before, the ignition key tumbler assembly is replaceable.
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Eric
Hi Performance Automotive Service (formerly OVO or Old Volvos Only)
Torrance, CA 90502
hiperformanceautoservice.com or oldvolvosonly.com

Hi James,

Someone had a post recently with an 1800 with the key tumbler not turning
Maybe a tumbler pin hanging up and he had to file something.
See Here:
https://www.brickboard.com/RWD/volvo/1690708/1800/ignitions_switch_woes.html

Have you tried lubing the tumbler with graphite?
Worn key? Try another key.

If the key turns and nothing happens, then you worry about the switch section.

Cheers from Swampscott, Bill

That post is for a locking steering column so it doesn't totally apply to the OP's problem.

The problem most likely is a worn key or worn tumbler assembly issue.

Your advice to use some graphite in the tumbler or another key is a good idea.

The tumbler assemblies are replaceable and are available new, but I've experienced some problems with the newer ones.

The most recent problem was the pin that holds the tumbler in the switch assembly fell out and made the new tumbler useless.

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Eric
Hi Performance Automotive Service (formerly OVO or Old Volvos Only)
Torrance, CA 90502
hiperformanceautoservice.com or oldvolvosonly.com

Hi Eric,

Plan B, if all else fails would be to find a good local locksmith
that might find it an easy job.

Best regards, Bill