Fixing and Learning About Old Mortise Lock

Beign

We have two storm doors from the 1930s or 40s with old storm door hardware. The deadbolt was not working on either set. So, I opened them both and found a lot of dirt in one and a lot of rust in the other. I found a flat piece of metal in both and was not sure what it was for. The deadbolt seemed to work fine with the turn knob without this piece of metal. After searching for awhile, I’ve learned that it is probably a flat spring. I am not sure what the purpose of this spring is and whether or not I need to find a replacement/ install it. I am including pictures of the one that I opened that was filled with rust. I found a broken piece of metal in there. The picture of the full piece of metal is from the other mortise lock that had been filled with dirt. I would appreciate any help in understanding the purpose of this spring, where it should be located, and whether I need to include it in my repair.

Thank you!

Pschiffe

Beign wrote
I would appreciate any help in understanding the purpose of this spring, where it should be located, and whether I need to include it in my repair.
Thank you!

I’m guessing that spring likely applied downward pressure on the deadbolt arm and thus kept it parallel with the bottom of the lock case.

Pete Schifferli

[unknown]

Beign

Pschiffe wrote
I’m guessing that spring likely applied downward pressure on the deadbolt arm and thus kept it parallel with the bottom of the lock case.

Pete Schifferli

So, is it necessary to replace this broken spring?

[unknown]

peerless

It looks like it sits on the bottom of the lock case, the 22½° bend in the spring (as shown in the right of your photo) should face UP against the hub for the bolt. The bolt hub appears to have a teardrop shape that the little bend would interact with providing a detent function.

Any COMPETENT locksmith should be able to fashon new springs for the locks for not an arm or a leg. New ones would be advised as the rusty one is probably on it’s deathbed.

Hope this helps some, by the way, what area of the country are’ya?

Beign

peerless wrote
It looks like it sits on the bottom of the lock case, the 22½° bend in the spring (as shown in the right of your photo) should face UP against the hub for the bolt. The bolt hub appears to have a teardrop shape that the little bend would interact with providing a detent function.

Any COMPETENT locksmith should be able to fashon new springs for the locks for not an arm or a leg. New ones would be advised as the rusty one is probably on it’s deathbed.

Hope this helps some, by the way, what area of the country are’ya?

.

Thank you. I am in Nashville. I am not aware of any locksmiths here that specialize in old locks.

[unknown]

Pschiffe

Beign wrote
So, is it necessary to replace this broken spring?

Yes, I would. Flat spring steel assortments for locksmith use are offered by ESP Hudson, see link:
http://www.hudsonlock.com/online_store?category_id=101
Stocked by many locksmith distributors.

Pete Schifferli

[unknown]

Dean Nickel

As to the purpose of the spring is to keep the lock from locking if the door closes with any force. So half locked or unlocked doesn’t happen as well.

dll932

Beign wrote
Thank you. I am in Nashville. I am not aware of any locksmiths here that specialize in old locks.

Mortise locks haven’t changed a whole lot over time. A competent ’smith who’s been in the trade a while should be able to hook you up.

[unknown]