Weak solenoid, bit odd

[strobey]

Got a very weak solenoid on a WPC95 pin.

Its a low power 27-1200 coil, used as an underpass kicker to move the ball between ejects.

Coil itself is actually very tight in the metal assy, no play at all, but the plunger feels loose and is free to move by hand.

However when it energises it just feels like it locks on and doesn't have any directional pull.

If I hold the plunger coil half way and energise it doesn't really do much other than vibrate, but it's solid and hard to move.

Measured ~75V both sides of the coil

Coil resistance is 13 ohms

At backbox, shorted transistor lug to ground, no change.

At coil, shorted violet return to ground, no change.

Could this just be a mechanical problem? Maybe the coil sleeve isn't working as it should? Is the plunger being pulled into one side of the coil instead up outwards?

Thanks for any thoughts!

Tim

 

[carl lawrence]

Could be the coil it’s self, as when the power is on the coil collapse around the sleeve/plunger ,so replace coil to rule it out of the equation .

 

[strobey]

I think that's the stage I'm at. It's also a repro coil by the looks of it so maybe it's poor quality.

Might just do the coil sleeve first, looks like it should have a flanged end but it doesn't.

 

[carl lawrence]

An old trick if it is was a coil was to fit an old metal coil sleeve in .

 

[Spandangler]

Left field, but wpc 95 coils go weak if there’s a blown fuse somewhere. It’s normally a bunch of coils though. Might be worth a look.

 

[strobey]

Yeah I did read that, but this is the only one