Look at the parts diagram in the manual and at yours. Anything different or missing ? Coil stop or rubber grommet maybe ?

LTG : )™

Can you lift them by hand? It might not be a problem with the coil if they are binding.

_{Post edited by herg: Should have read closer}
I missed it the first time through. Time to get some sleep, I guess.

The spikes are sitting just below the surface of the playfield?

I'd check connections from the coil to the power driver board. Maybe a wire in an IDC connector not making good contact anymore.

LTG : )™

Here's a problem I had with mine. The set screw that adjusts the height has a plastic tip that the plunger rests on. The plastic tip broke off of mine and it was making metal to metal contact and wouldn't fire. I could put a thin piece of plastic between them and it would fire. I just changed the set screw and it fixed the issue. Maybe check that?

Since you say they raise about 1/2" when activated, it doesn't really sound like an electrical problem to me. I'd be focusing on mechanical issues.

Couple of questions:
1) does it move freely as an assembly both out of the game and installed in the game?
2) do you get more than 1/2" travel when moving freely outside of the game?
3) when the spikes activate, do they move up really quickly, or does it take time to get to the "up" position
4) have you checked to see if there is any dirt or other gunk in the holes for the spikes, there is not much clearance between the holes and spikes so anything trapped in there could cause it to bind
5) any bent spikes that don't seem to be in alignment, or parallel with the rest of the spikes
6) did you check voltage at the coil on firing

I'm assuming, based on your notes that you can get more than 1/2" in game if you move it by hand. I'm also assuming that when you move it by hand in game you don't feel any resistance during travel. Weird.

Scott

Unless they don't get enough power to go up. And since it's both of them, not too likely they'd both have the same problem, starting the same time, and apparently not after they have been worked on.

LTG : )™

Sounds like it's only one set.

I'm not trying to argue; that would be pretty stupid considering your experience. I'm just putting forth my best guess. Your own first guess was mechanical issues as well.

Right you are. Thank you.

Left assembly works, then look it over and look for any differences to the right one.

LTG : )™

This is why I was asking if the spikes are just below the surface of the playfield.
The lower it is down in the cabinet, the tougher it is for the assembly to kick it up to the correct height.
Try adjusting the set screw upward anyway and see what happens.

I worked on a TOTAN with one assembly that would not kick up at all. Found it was completely missing that set screw.

Thank you for the confirmation on the height adjustment.

Does it only kick up that same amount in the coil test as it does in game play?

If it kicks correctly in coil test, I would think your optos for that right spike could use a cleaning.
Hell, clean them anyway.

It gets more power in test.

There has to be something different from the working one you just aren't seeing.

LTG : )™

MB, CC, and MM have the same driver board if you want to try it in TOTAN to narrow it down to playfield or board issue.

And the rubber grommet is there that the plunger rests on ?

LTG : )™

Did you ever get around to measuring the voltage at the coil?

I don't especially like doing this, but you could manually fire the coil using a test lead. If that still didn't work, you could eliminate the control circuit as a possible cause.

Could you post what Borygard said? Chisel and sledgehammer are not usually in my pinball toolbox.

Awesome. Be sure to mark this thread as resolved in case someone is searching for the same problem later. That way they know it leads to a known solution.