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Removing stuck coil sleeves?

Wizards_Hat

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Joined
Jul 22, 2011
Messages
241
Location
Audenshaw, Manchester
Has anyone got any useful advice on how to remove stuck coil sleeves?

Currently trying to revamp the flippers on a TZ that look like they've not been touched in ages & the coil sleeves are stuck fast in the coils. Whenever it's happened in the past I've spent ages trying to gouge them out with a screwdriver & they do come out eventually, in a million pieces, but I'm sure there must be a better way.

Tried finding a socket that was exactly the diameter of the coil inner so I could push it out, but had no luck - they were either just too small & jammed inside the sleeve, or too big to fit in the coil.

Any ideas?

Regards,
Dan.
 
I'm afraid there is a most likely a reason why the coil sleeve is stuck.... The coil has overheated at some point and the plastic housing has contracted to the point where it is no longer the correct size/shape for the sleeve. It is usually an indication of shorts developing in the windings resulting in a lower resistance, or the coil has at some point been stuck on and overheated.

If you can't get the old sleeve out smoothly, then it is unlikely that you'll get a new sleeve in smoothly. If I can't push the old sleeve out using a new sleeve, then that's when I throw the coil in the bin.

I've hack-sawed a few shrunken coils in half out of interest over the years and you can usually see the signs of discoloration / overheating on the inner winding
 
Thanks for the advice - though I can't afford to replace all 4 coils on this TZ (all 4 flipper coils had stuck sleeves).
3 of them took new sleeves without much effort though (4th was a little tight, but not exceptional) & all flippers seem sharp now (obviously all other flipper parts have been cleaned/replaced as appropriate too).

Does everyone else just bin their coils when the sleeves are stuck, or do you have any tips/tricks for removing the sleeves?

Regards,
Dan.
 
You could try squeezing the protruding end of the sleeve with pin nose pliers, and squirting some gt85 between the sleeve and the coil. Or pushing a blunt needle (bodkin) between the sleeve and the coil, again following up with some gt85

Gt85 is Teflon spray and is very good at penetrating seized hinges, bearings etc. The low viscosity fluid evaporates to leave a layer of Teflon behind, so it is not a gunky product.
 
I have one of the older brass sleeves which I use to remove any hard to move plastic sleeve.
 
I pup the coil with stuck sleeve into boiling hot water for a few minutes to soften the plastic, makes it easier to remove.
 
Loads of good tips here! Like the boiling water trick!

In my experience (and it's fairly limited to the 3 pins I own plus a knackered but fully populated playfield I got for Paragon spares) if the coil sleeves don't come out with either a firm thumb press or gentle tap on the bench then something is wrong with the coil. I've had stuck brass sleeves as well as plastic.

After battling with this Bally AQ-25-500/34-4500 flipper coil I came to the conclusion it was shot. The resistance readings were a little different to the others but maybe still just about within the ok range. But look what I found when chopped it in half. The inner heavy gauge coil is slightly blackened from over-heating and the sleeve wouldn't budge because it was fused to the bobbin!

farm6.staticflickr.com_5588_14875870364_7e51481fda_c.jpg

Compared to the value of your pin the price of a coil is negligible! My new Bally flipper coil was £10, although in my case I guess that's a lot compared to the £125 purchase price of the pin! Probably most important part in the game though :D
 
Loads of good tips here! Like the boiling water trick!

In my experience (and it's fairly limited to the 3 pins I own plus a knackered but fully populated playfield I got for Paragon spares) if the coil sleeves don't come out with either a firm thumb press or gentle tap on the bench then something is wrong with the coil. I've had stuck brass sleeves as well as plastic.

After battling with this Bally AQ-25-500/34-4500 flipper coil I came to the conclusion it was shot. The resistance readings were a little different to the others but maybe still just about within the ok range. But look what I found when chopped it in half. The inner heavy gauge coil is slightly blackened from over-heating and the sleeve wouldn't budge because it was fused to the bobbin!

farm6.staticflickr.com_5588_14875870364_7e51481fda_c.jpg

Compared to the value of your pin the price of a coil is negligible! My new Bally flipper coil was £10, although in my case I guess that's a lot compared to the £125 purchase price of the pin! Probably most important part in the game though :D

This is exactly what I was describing earlier, and you can't beat seeing a picture. Come on guys, if the sleeve is getting stuck, throw the coil in the bin, it's failing.
The longer you leave it, the more likely you are to start ending up with board faults as well.
 
I managed to press out a stuck plastic coil sleeve out of my Dolly Parton by pressing the coil down using both hands gently on a bit of thick rubber, it was quite some work but it worked.

Didnt save the coil though, i had to swap it for a new one.
 
Tight sleeves mean throw the coil in the bin and buy a new one. Keeping coils like that puts more stress on the electrical components which drive it, you'll struggle to get a new sleeve in, and once the new sleeve starts gripping the plunger you'll be losing performance.

Coils aren't really that expensive compared to other parts. They are a disposable part never intended to last forever.
 
I get stuck sleeves all the time with EMs. Not as a result of meting though, but a s result of age and crud build up. I use a nut spinner to push them out and also a wee dab of Iso alcohol as a lubricant. If it still does not budge then i get a pair of snips and leaver the bastard out. As i say. In all cases the coil is not burned out. After a clean, the new sleeve always goes in with a firm thumb press and some more alcohol. Agree with others though, if after you get the sleav out, it looks distorted, just bin it. You are just over stressing your boards and eventual the coil will short any way. Unless it is an EM, in which case just stick a nail over the fuse holder... That last part was a joke just in case...
 
I get stuck sleeves all the time with EMs. Not as a result of meting though, but a s result of age and crud build up..
In all cases the coil is not burned out. After a clean, the new sleeve always goes in with a firm thumb press and some more alcohol.

I know EM's don't have delicate cicruitry like SS' but if you're having to force sleeves in with lube then those coils are knackered and need to be replaced.

The reason why they are tight is because the shellac has worn off of the copper strands, shorting them together, and slowly they are getting tighter and tighter. It's what happens to all coils with use, as electricity is pumped through them they expand and contract which is what wears away the coating (and causes solenoid dust).

Put a multimeter on them to check resistance and compare with new.
 
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