I always use whatever parts I have on hand before ordering new ones.

In the case of that relay it is best to take it apart and clean it all up before doing any modifications to spring tension as that might only be compensating for another problem.

I try to clean steppers so that the existing springs do not need cutting. Sometimes though, I'll cut a couple loops off if nothing else is working. I try to avoid buying any unnecessary pinball parts. It is expensive enough without have to pay someone a couple dollars for a ten cent spring.

I'd only adjust springs as a last resort. Never seen one with 'wrong' tension (unless it's already been stretched), not sure if that actually happens? The few times I've thought it was, the new spring had the same problem. Cleaning has always worked for me though, never had the need.

Over time (40+ years!) springs loose their tension. i'm not big on ordering new springs for a variety of reasons, so cutting a bit off to increase tension seems reasonable. But yes as someone mentioned, only after you've cleaned everything and it in fact actually needs more tension.

As a rule, no. But, I have cheated a little on those pesky AS units by bending the spring tab up just a bit to slightly increase the spring tension.

I've had to do this on some Gottlieb 1970's vintage score reels.

Yes I have done this all the time. Springs get weak, cutting off 2-3 coils after eliminating everything else not going to hurt.

Spent $40 getting all new drop targets from my Night Rider pin as not all would stay up during reset... made no difference till I shortened the springs a few coils and now they work great.

Anyone needs some used drop targets? Slightly worn, nothing wrong with them.

I do! Mata Hari needs a set

If that AS unit spring is similar to other springs in your ACD (or another one of your games) you could swap it. Just to try it out, to find out if the spring tension is a problem. A spring from one of the relays for the scoring look the same.

I confess to doing this often. I don't have a supply of all sorts of springs sitting around, and tend to forget to order the one or two I need when ordering other parts. It's expedient, and if you screw it up, you'll for sure remember to order the real part!

I always over order when it comes to something as simple as a spring. Buy a few different springs, coils, sleeves etc. It's not that expensive. It's the annoyance of not having the right part that's frustrating.

I've never seen springs lose their tension from just sitting. And the price is right.

I am so annoyed by those people that tighten springs by hooking them a few loops up, leaving the rest of the spring that I don't cut my springs. It's not evil or anything to cut a spring, just one of my pet peeves, I guess. I have turned one end to add tension, but it's not like the old thing suddenly springs back to life. It is pretty limited how much tension you can add that way.

Usually a good cleaning solves most of my spring problems. If not, I always try to have some new springs on hand. If a new spring doesn't solve the problem, then I know that there is another problem lurking in the midst.

Yes!