Replacement thumbturn lock for Trapp storm door

A handy person from Michigan says:
I am on the mad search for a replacement lock for my Trapp storm door. Will your 40-089 work in this lockset. My existing lock is an oval shape with the same dimensions as the 40-089. Thanks for your help.
thumbturn lock
Profile picture of Dave Sr.
Dave Sr. from SWISCO responded:
At one time, the manufacturer had two versions of this key tumbler. They both looked the same, but were not interchangeable with one another. Yours does appear to match up with the 40-089, but unfortunately there's no real way to know until you try it in your door. You might need to replace the complete handle. Some customers have said it works fine, but others have reported that it does not. I'm sorry we can't give a more definitive answer.
A home owner from Macomb Michigan says:
FOLLOW UP

Hey Dave, this in my question above and I thank you for answering it honestly. I took a leap of faith and purchased the 40-089 hoping it would work. When I got it I compared it to the old lock (pictured) and it appeared to be identical. When I attempted to install there were a few problems. First the one set screw that anchors the lock in was slightly offset. I drilled the lock plate on the door about a 8th of an inch to get a good fit and not cross thread the screw. After I got it in I tried turning the thumb turn.....nothing. It would not turn. After further inspection and a complete removal of the lockset I discovered that the 2 little pieces that turn to actuate the lock were a fraction of an inch too long on the 40-089. I put them on the grinder and took about a 16th of an inch off of them, wire brushed and grease the whole lock and presto.....fully functional. Thanks for the direction and I hope this helps someone else out there.
Profile picture of Dave Sr.
Dave Sr. from SWISCO responded:
That's great news! Thank you so much for the rundown on how you got it to work, I'm certain this will help others in the future. We greatly appreciate your business and assistance. Please let me know if you ever need anything else.
How to install the Swisco 40-049 Mortise lock set.
How to install the Swisco 40-049 Mortise lock set.
VIDEO
WATCH >
How to flip a storm door mortise latch.
How to flip a storm door mortise latch.
VIDEO
WATCH >
Reply to Thread
Use this form to ask a follow-up question or to share your experience regarding this subject.
(your email address will be kept private and is only used to inform you when a response has been made)
Current wait time is 3-4 business days
We promise that one of our experts will personally get back to you as soon as they are able. Thank you very much for your patience and understanding. If your inquiry is time-sensitive, please feel free to reach us at (888) 991-1929 or at help@swisco.com.