Marvin Casement




Thanks for posting. It looks like the link arm on your operator, or the part of the arm that connects to the bracket on the window sash, is attached to the bottom of the gear arm (or the part of the arm that connects to the operator box). The 39-316 has this the other way around. In addition, your old operator's link arm has an 'offset' that the 39-316 arm lacks. Based on these features, I think the 39-172 is the better match. See below.

Now, while I think the 39-172 is the best replacement, you'll note that this operator has the same issue--the link arm is 5" long, rather than 4-1/2". Unfortunately we have no version of this operator with a shorter arm. There's a few solutions to try. One, you could try installing the new operator as is and see if it works--depending on the window setup, it may. If that fails, you could swap the link arms on the old and new operators by drilling them out, and then attaching the old link arm to the replacement operator with a rivet like our 62-014B. Just note that modified items cannot be returned for refunds. Let me know if you have any other questions.