2LTE Starter trouble shooting - solenoid clicks but wont turn over

[MarkusMcBride1244]

Hey guys, I've tried to use the resources I have and do research but I'm a little out of my depth trouble shooting this starter now.

1990 surf, 2LTE starter pn 28100-54250
Starter solenoid was giving me a singular "click" but no turning over. I removed the starter to check the terminals. Power side terminal was worn down a bit but still within spec at 1.90mm thickness. So I filed the other side down and put it back together.
I tested it on the bench and 1st crack, same issue, "click" - no spin. But right away after that, it operated 15x as it should. So I reinstalled it.

Reinstalled: truck turned over right away. Didn't start right away but that's another issue (it was sitting a while and its cold out). So I had to run the starter I'm sure 10x before the truck ran and it worked every time.
I let the truck run 10min, then it sat for 10min. And then it wouldn't turn over again, just the same click from before.
An hour later after dinner, damn thing started right up! I tested it a few more times and it did give the odd click but I'd try again and it would go. So I'm back to square 1 with a starter I don't trust.

What do you guys think? Could it be the plunger? From the repair manual I have, I just saw that it says to use a press to push the terminals down before you tighten them, see below. Has anyone changed/filed these terminals before and did you use a press!?? What's that all about?

[MarkusMcBride1244]

I ordered the plunger, new terminals both sides, and the spring. Saw online that the contact of the plunger to the terminals needs to be near simultaneous and that any pitting from arc can cause it to be intermittent. I recall the copper washer on the plunger being a little pitted.
While I have the starter down the second time, I intend to check the brushes for spec and possibly even the armature for dead spots. Just trying to save myself from forking out $500+ for a Taiwanese unit. I have another vehicle in the meantime.

Any thoughts or advice is welcome

[MarkusMcBride1244]

Well I'll reply to myself in case anyone can use it down the road. The repair manual I am using is the best I've ever come across. Runs you through how to trouble shoot each component of the starter. My armature and brushes are good. I installed new plunger and terminals, ball bearing and spring ta boot. Shout out the John at RADD CRUISERS in Kamloops. I had to CLEAN the crap out of the internals (and external). That pesky oil leak up around the throttle body somewhere has been leaking down onto the starter for years I'm assuming.
I greases the bearings of the armature as per the manual and cleaned up the commutator with a sharp little pen knife. Break cleaned a ton, next to heater to dry out and REASSEMBLE.

So far I've only tested it on the bench but it worked every time. Here's to hoping this will be the last time I have to remove/reinstall it. A bit about that if anyone wants to know:
REMOVAL FROM VEHICLE: Most access through wheel well, for the bracket and 1 of the two 17mm bolts, but the top bolt required about 2 feet of extensions and a swivel adapter for the socket. Have to run the extensions along side the transmission. Get a good light shining down on the bolt from above first, I unbolted the fuel filter to get it out of the way to see the bolt, then shined light good, then crawl under and use extensions and a impact. (I broke it first time by hand/final tighten by hand).

Pictures or it ain't true:
You can see in the one pic, the power side terminal is worn down considerably. Still within spec as per the repair manual, but not ideal and not level with the other one.
Other pic is armature.
Then brushes, lots of life left
and then all the bits together