Yale model 424 padlock

YALE7750

Hi everyone,

I’m looking for any info pertaining to the Yale 424 padlock–such as years of production, parts diagrams, anything really. This is removable core but not SFIC, uses the large 1210 cores. I have one of these that has what appears to be a broken spring in the locking mechanism– it will not lock unless you rotate the key backwards. It has an American lock type ball bearing system, but I see no way to remove the driver & locking balls. I’ve only come across these once or twice in 30+ years, so I hope to fix it instead of damaging it trying to disassemble it.

Billy B Edwards Jr. CML

YALE7750 wrote
Hi everyone,

I’m looking for any info pertaining to the Yale 424 padlock–such as years of production, parts diagrams, anything really. This is removable core but not SFIC, uses the large 1210 cores. I have one of these that has what appears to be a broken spring in the locking mechanism– it will not lock unless you rotate the key backwards. It has an American lock type ball bearing system, but I see no way to remove the driver & locking balls. I’ve only come across these once or twice in 30+ years, so I hope to fix it instead of damaging it trying to disassemble it.

Can you just push the shackle in and have it lock? If not it is likely the padlock function is ‘Key Retaining’ which means you can never leave the lock unlocked without the key in it. To change that function you would need a new actuator and a spring to reposition it for the ‘Non Key Retaining’ function.
BBE.

[unknown]

Pschiffe

YALE7750 wrote
Hi everyone,

I’m looking for any info pertaining to the Yale 424 padlock–such as years of production, parts diagrams, anything really. This is removable core but not SFIC, uses the large 1210 cores. I have one of these that has what appears to be a broken spring in the locking mechanism– it will not lock unless you rotate the key backwards. It has an American lock type ball bearing system, but I see no way to remove the driver & locking balls. I’ve only come across these once or twice in 30+ years, so I hope to fix it instead of damaging it trying to disassemble it.

The Yale 424/434 LFIC removable core padlock is apparently of fairly recent vintage but was discontinued in December, 2009; replaced by PD524/PD534. The difference appears to be that the older model only accepted the 1210 6-pin conventional core while the newer version also accepts 1220 7-pin conventional as well as Security and KeyMark cores. The Yale LFIC (large format interchangeable core) mechanism was first marketed around 1960 as a competitive alternative to the Best, now Stanley Best Access Systems; SFIC (small format interchangeable core) which was introduced back in the 1920s. Thus your padlock could date from about 1960 to 2010.

Pete Schifferli

[unknown]

YALE7750

Thanks for the info; apparently I have an older model that takes only 6 pin cores. The shackle is also marked “stainless steel”. 7 pin cores (1220) are too long & 5 pin (1200?) too short. It’s definitely a non-key retaining model with a 2 piece driver & broken spring. The mechanism is held in by a ring that’s pressed in & cannot be easily removed. I had no idea they continued producing it post 1980’s–I’ve never seen one actually in use since then. I wonder if Medeco 31s cores fit?

Yale7750

Pschiffe

YALE7750 wrote
I wonder if Medeco 31s cores fit?
Yale7750

The (Medeco) 31 series core was originally only available in the 6-pin size to replace Yale 1210 cores but later retrofit jobs required the addition of a 7-pin size core in 1988.*

Pete Schifferli

[unknown]

Billy B Edwards Jr. CML

YALE7750 wrote
Thanks for the info; apparently I have an older model that takes only 6 pin cores. The shackle is also marked “stainless steel”. 7 pin cores (1220) are too long & 5 pin (1200?) too short. It’s definitely a non-key retaining model with a 2 piece driver & broken spring. The mechanism is held in by a ring that’s pressed in & cannot be easily removed. I had no idea they continued producing it post 1980’s–I’ve never seen one actually in use since then. I wonder if Medeco 31s cores fit?

Yale7750

The Medeco cores were designed to be a direct replacement of the Yale core when the White House exempted Medeco from patent infringement of the Yale patent in 1970. Once the Yale patent ran out the product was cataloged and offered to the public.
BBE.

[unknown]