EM – Score Reels – Gottlieb

Guide To Gottlieb EM Score Reels – Cleaning and Fixing

Prior to starting, please read the introduction and parts needed page.

Understanding the Switches

Note that the open / close state of these switches changes from generation to generation of the reel.  The following description is for the 2nd and 3rd (last) generation of the Gottlieb Dragon reel.

Gottlieb EM Score Reel Switches
Gottlieb Dragon Switches

Each Gottlieb score reel has several switches, each one crucial to the operation of the pin.  Failure of any switch in any reel can prevent the machine from entering game play.

  1. This tells the game that the reel is reset.  If this does not work, the game will never start.  The scoring reel in the cabinet will keep spinning.  Also called the ‘zero switch‘. 
  2. These switches make contact from 1 – 9. If these do not make contact, the score wheel will not move during the startup sequence.  This is sometimes called the ‘runout’ switch. 
  3. This switch makes contact on 9 and tells the pin to carryover the score to the next higher reel.  This switch is usually absent on the highest score reel.  Also called the ‘nine switch‘ or ‘On Add‘.
    Gottlieb Score Reel EOS switch
    EOS Switch
  4. This switch is a EOS (End of Stroke) switch.  This makes sure that the solenoid is powered long enough to pull all the way in.  When this switch opens, the power is removed from the solenoid and the number advances.  If it opens too soon then there is not enough power.  Not at all and the solenoid stays energized.
  5. This is a second ‘nine switch’ or ‘On Add’ switch.  In conjunction with #3 switch, this switch is in series and the two are closed together momentarily when the reel advances from 9 – 0.  This then advances the next higher reel.

For 1 – 3, each switch has two contacts.  These are electrically connected together and are redundant.  If either contact works, the pin will work.  There are two contacts to increase reliability, so it is important that both be cleaned and make contact.

Switch sequence for 2nd and 3rd generation:
Switch Zero 1 – 8  9
3 (top) open open closed
2 (middle) open closed closed
1 (bottom) closed open open
Switch sequence for 1st generation:
Switch Zero 1 – 8  9
3 (top) 0pen closed closed
2 (middle) open open closed
1 (bottom) open closed closed

Step By Step Instructions For Making a Gottlieb Score Reel As Good As New

[For each image, click on it for a larger picture.]

Disassembly

The first time will be confusing and feel like it takes a long time.  Trust me in that doing it a second time will be a lot quicker.  After a while, you will be able to do this quickly and easily.

Note: For ease of reassembly and reference positions of parts, it may be helpful to have each score reel set to zero prior to disassemble.

'C' retaining ring
‘C’ Retaining Ring

1) Remove the score reel from the cage located in the backbox / header.  There is a tab holding the reel in place – push it to the side to remove the reel.

2) Remove the ‘C’ retaining ring and place it in your parts storage bin. If using muffin tins, number the holes (with a pencil!) and place this in the first hole.  Move from hole to hole as you remove parts.

Remove the two screws holding the board in place.

3) Loosen and remove the two screws holding the circuit board in position – while holding the other end in place.  When these two screws and retaining ring are removed, all sorts of parts and springs can pop off and become airborne. 

Swing the board out of the way. Hold the reel in place.

4) Carefully lift up the circuit board while holding onto the parts located on the numbered reel.  There will be a metal electrical contact, a plastic piece, the reel and a spring all waiting to fly out into your room.

This next step in important:  Note the position of the metal contact.  The single contact will be pointing to between the ‘5’ and ‘4’ on the reel.  The backside points to between ‘0’ and ‘9’.  When reassembling, it must be put back to that position [see photos].

Numbered score reel

5) Remove that plastic ring and metal contact and place it into your parts holder while holding the rest of the spring loaded parts in place.  Underneath the metal contact is another plastic piece that must be carefully removed, while holding the number wheel in place. 

plastic piece with spring behind it
Circular plastic part with gear teeth engaging the slide in step 7).

6) Remove the numbered score reel and store it off to the side.  

When removing the reel, this plastic part with gear teeth will be pushed out by the spring that is underneath.  Prior to removing this, it is important to study its operation for reassembly.

plunger assembly
Plunger mechanism connected to slider and the slider spring.

7) Push the circular plastic part with gear teeth back down so that it engages the teeth of the slider part underneath.  Now push the plunger into the solenoid and pull it back out.  The left most gear tooth will fit into the left end of the slider [see photo]. The teeth on the wheel must line up so that they meet through the entire movement of the slider.  If the circular plastic piece is positioned improperly, the teeth will ‘run out’ either when the plunger is pulled in or pushed out.  Note how to align the teeth between these two plastic pieces for reassembly!

Lever location in switches

Now remove the plastic wheel and the spring underneath and place it aside.

Wire Lever in step 9).

8) Next we will be removing the parts attached to the plunger.  First remove the bottom spring on the bottom of the slider mechanism.  It is important to keep track of where each spring goes.

remove this switch
Switch in step 10).

9) [This step is optional.  Some people leave this in place.] Note the wire lever above and carefully note its position in the 3 leaf switch.  These are switches 1, 2 & 3 noted at the beginning of this page.  When reassembling, this wire must be positioned exactly between those leafs. Now, disconnect the spring holding onto the wire lever above.  Remove the wire and spring and place aside.

The removed switch.
10) Switch positioned out of the way.

10) We want to move the EOS switch, #4 and #5 (above) to get it out of the way.  Some like to remove one screw and swing it up out of the way.  I like to remove it completely – however, if all the screws are removed at once, the switch can literally fall apart.  

Solenoid bracket
Solenoid bracket, plunger and edge of slider.

Loosen both screws and then remove one.  Swing it up all the way and then reinsert the screw and lightly tighten the nut.  The do the same to the other screw and nut.  Finally, tighten the screws and nuts down so they don’t fall off.  Alternatively, the switch can be wrapped with a rubber band to keep it together.

Solenoid bracket with screws removed
Slider to the right, coming off the plunger.

11) We are almost done with disassembly.  Now remove the four screws holding the solenoid bracket in place.  The remaining components will come loose.

If the coil sleeve is stuck in place, use a small screwdriver to free it.  If not, it might break during this step.   

12) The next set is awkward: Tilt the bracket and solenoid coil up and back while working the slider attached to the plunger.  The bracket will have to be tilted about 45 degrees.

disconnecting the parts

It is possible to remove all of this without having to unsolder the wires.  Take note as to how you do this step because it will be doubly difficult to repeat it going back together. 

Note that as the plunger comes free, there is a ‘U’ shaped guide where it connects to the slider.  During reassembly, this guide has to oriented upright to receive the slider.  It takes sharp eyes to see this guide. 

Plunger and slider
U-shaped guide

13) Remove the slider and its spring to expose the base.  Also remove the plunger from the coil and set aside. 

You have finally completed disassembly and are ready for cleaning, then reassembly. 

Cleaning

coil sleeve14) Remove the coil sleeve.  Either clean it with 91% isopropyl alcohol or replace it.

scored surface
Wear spot on the plate to be polished and lubricated.

15) Also wipe around the coil for dirt as any remaining can gunk up an otherwise clean mechanism.

16) Take a look at the plate where the components move back and forth. This has to be smooth and clean in order for the reel to work smoothly. 

dremel to shine the surface
Carbon brush removing wear on the plate.

 Take a microfiber cloth and clean the surface with alcohol.  Look for any groove or gouge marks.  These need to be removed completely.  Then bring out your Dremel and the 1/8″ carbon brush and/or sanding disk (see parts list) and shine this surface.

cleaned area17) When completed, the surface of the plate should be free of gouges and anything else that might cause the mechanism to drag across it.  Clean that up with a microfiber cloth.  Then, using small amounts of Mothers Mac & Aluminum Polish (see parts required), clean until no more blackened oxidation is removed. Then wipe clean with 91% isopropyl alcohol.Slider

Dremel buffing tool
Dremel polishing up edge of the slider.

18) Use alcohol and clean off the edges of the slider mechanism. Take out the polishing or sanding wheel for the Dremel and shine up the edges of the slider mechanism that connects to the plunger.  The edges of this get worn and this causes a drag as it moves back and forth – we want it nice and smooth.  Use a q-tip to clean the plastic ‘gear’ teeth also.

buff the bracket to remove burrs
Dremel polishing up edges of coil bracket.

19) Grab the bracket and buff that up also, in the area where the slider and bracket meet.  This must be smoothed so that the slider will move freely.

Slider guides

20) When reassembled, the slider will move along two guides (see photo – one is hidden from view).  Take the dremel carbon brush and clean any metal ‘burrs’ that might prevent the slider from moving freely.  Clean with alcohol.

plunger
Cleaning the plunger.

21) Grab the plunger and clean it up by wiping with isopropyl alcohol.  If there are any rough edges, remove those off with the polishing wheel on the Dremel.  The edges can be removed with a file, or a dremel sanding wheel, polishing wheel, or the 1/8″ carbon brush.

Clean up the switch contacts
Carbon brush cleaning tungsten contacts.

22) If the switch contacts are tungsten (gray metal and pitted), take back out the 1/8″ carbon brush and clean them.  If the switch contacts are copper colored and not pitted, then clean them with a q-tip and 91% isopropyl alcohol. Be sure to clean the EOS switch also.

Cleaning the wheel
Cleaning every nook on the score reel.

23) Grab the numbered scoring reel and clean it.  It is possible to carefully clean the numbers with a gentle cloth and water with, perhaps, a small amount of detergent.  But be careful as in a lot of cases, the numbers will rub right off.

But more important is to use a q-tip soaked in isopropyl and a cloth and clean every nook and cranny in that wheel.  Any remaining dirt or goop will prevent prevent the wheel from locking into position.

Cleaned circuit board24) Use the Mothers Mac & Aluminum Polish and clean the circuit board until it shines. Clean until no more blackened oxidation is removed. Then wipe clean with 91% isopropyl alcohol. Use plenty of alcohol to remove all of the polish.
It is only necessary to shine up the area where the contact is being made. 

Inspect where the wires are attached.  Re-solder if necessary (add new solder to make it easier to melt).  Be sure there is no extra solder making contact between the wires or across the board traces.Electrical contacts

25) Clean the metal electrical contact that rotate around the circuit board.  Depending on their condition, they can be cleaned with 91% isopropyl alcohol and/or the 1/8″ dremel carbon brush (gently!).

Lubrication

dry teflon lubricantMost pinball parts are designed to run ‘dry’ meaning no oil.  But we now have ‘dry lubricants’ – meaning Teflon, so they can be used without the parts getting gummed up.

lubricate circuit board 26) Grab the Teflon lubricant and a Q-tip and lubricate the circuit board (lightly – 1 drop on the q-tip might be sufficient) and the metal area just shined on the bracket surface.  Wipe off the excess on the circuit board with a microfiber cloth.  If too heavy, the electrical conductivity might be poor.

Do not get any lubrication on the switch contacts.

lubricate metal surface

27) Next, lubricate the sliding surface on the bracket polished up above in step ’17)’.  Use the Finish Line Dry Teflon lubricant (or equivalent).  Do not use oil of any type.

 

Reassembly

Bracket with coil and sleeveslider, plunger, coil bracket, coil, and coil sleeveThe first step is the reverse of the awkward step during disassembly: reinsertion of the coil, coil sleeve, bracket, plunger and slider.

 Just like this did not want to come apart easily, it tends not to want to go together easily.  This takes practice and a bit of trial and error to get it all to come together.

coil sleeve collar28) Grab the coil sleeve and insert it into the coil.  The ‘collar’ side goes towards the coil stop.  Then take the slider and hold it in position.  You may find that now is a good time to install the spring on the slider to hold it into place.  Place the coil bracket over the coil.

parts all together

Plunger with U-shaped guide

29) Grab the plunger and put it all together. Note that the ‘U’ – shaped guide has to be positioned with the open end up.  Be sure to insert the plunger through the coil bracket.  Be patient.  This looks easy in photos, but it will take some contortions to get it all back together.  In time, this will become a simple step.

Be careful not to force the parts together as this can warp the slider.

Switch wire
Install the wire lever exactly like this.

30) Screw the coil bracket into place.  

Install spring

31) If you removed the wire lever in step 9), reinstall it and its spring exactly like shown.  If the wire is in-between the wrong switch contacts, the pin will not work properly.

32) Be sure to put back the EOS switch near the plunger back into position as shown in the photo.  This was moved out of the way in step 10). 

Return tab
Reel Basket Backwards Latch 30)

33) Inspect this part – the Reel Basket Backwards Latch.  This is responsible for not allowing the score reel to turn backwards.  The top part should be flat and not bent inwards.  If necessary, use a switch adjustment tool to level it out.

Step 29).

34) Install the spring on the scoring reel shaft as shown.

Make certain that all the remaining parts are within reach for the following steps as you will have one hand holding the parts in the reel while the other is grabbing and installing parts.

plastic piece with spring behind it35) Refer to step 7) above and find that round plastic part with the gear teeth.  Insert it over the spring from step 31) and press down until it engages the slider.  Insure as you did prior to step 7) that as the solenoid pulls in, then returns out that the teeth of this part engage the slider throughout the entire run.

Score wheel
Insert score wheel 33)

36) While holding the plastic part in proper place, insert the score wheel (numbered wheel) on the gear part installed in step 32).  It is crucial to keep the gear from hoping out of its position.  It does not matter what number is displayed on the score wheel.  Hold the wheel in place to keep the spring from pushing it out.

Final two parts
Note position of the metal contacts.

37) Insert the metal contacts and final plastic part removed in step 5).  Note that the wide end of the metal contact has to point to between zero and 9.  If this part is not inserted properly, then various features on the game will not work properly.  Be certain to hold all the parts in place and not let the spring push out.  Note that some score reels will not have this contact.

Swing the board back into place. Hold the reel in place.

38) If this score reel has a circuit board, swing it into place over the score reel while holding all parts in place. 

Circuit board39) Insert the retaining “C” ring over the circuit board to lock all the pieces into position.  Insert the two screws holding the other end of the circuit board and tighten the screws.  

Almost done.  Now to check proper operation of the switches.

40) Refer to ‘Understanding the Switches’ at the beginning of this page.  Insure that switches 1), 2), 3) open and close as the score wheel turns.  Advance the score wheel by manually pulling in the plunger.   While advancing the reel, insure that the Reel Basket Backwards Latch engages to prevent the reel from turning backwards.   Inspect switches 4) and 5).  Insure that the EOS switch stays closed and opens as the plunger pulls in fully. 

All done.  Insert back into the cage, power up and check for proper operation of the reel.  Insure that as the reel moves from ‘9’ to ‘0’, that the next reel advances. 

Comments

Comments, including suggestions, improvements, errors, etc. are welcome (see below).

If you have a specific question about your game that does not directly apply to this page, please see our FAQ section.

 

12 thoughts on “EM – Score Reels – Gottlieb”

  1. I am in the process of restoring a Gottlieb PIONEER Pinball machine. After replacing one of the broken springs and cleaning the plastic parts, the score reel gets stuck on the “9th” position and won’t go to “0”? Replacing the Return Spring would help because the current ones look a bit rusty. Do you sell these springs?

    1. We are sorry, but we are an information website, not a commercial one, and do not supply parts. Please visit our external links page and check out the parts suppliers. For EMs, likely the best supplier is Pinball Resource. Its owner, Steve Young, is a fabulous resource for all pinball machines, and especially EM’s. But other sites, such as Marco and PinballLife might have those springs, also.
      In out experience, when the reel will not advance to zero, it can be a number of things, including:
      1) The switch(es) that the reel has to move are too tight.
      2) The main metal plate has worn groves on it which hang up the solenoid mechanism. This is the part that slides in and out of the coil. See step 16)
      3) Spring(s) are weak.
      Most people reflexively blame the spring(s) and sometimes tighten them. That is usually a mistake.
      Be sure to disassemble and clean the mechanism, then adjust as outlined above.

      https://homepinballrepair.com/index.php/external-links-the-most-complete-list-of-pinball-links/

    2. After reading your question in greater detail, we would suggest that while new springs might help, it is likely that the reel is dirty. When you have a chance, please read through our procedure of cleaning the reel. The part of the article where we clean up, remove scratches, then lightly lubricate the bracket with Teflon grease is one of the keys to giving the reel the extra power it needs to push up on that switch and advance to zero. Also, careful adjustment of the switch, plus cleaning of the plunger and coil sleeve will also help.

  2. Thanks for this post. I used it to fix a score reel on a 1970 gottlieb em. This is my first machine. I always knew there would be upkeep involved, but for a beginner it’s a bit intimidating. My issue was The tens reel was not switching over to the hundreds. It just continued adding up to 9 and then resetting back to 0. Using your information I was able to remove the score reel and clean the appropriate switch. The machine works great again. Thanks for the pictures and clear instruction.

  3. Hello, I have a Royal Guard. My issue is sometimes when I hit a 10 point switch or 100 point switch the the correct reel turns plus the one next to it or sometime the 10 point and 1000 point reel will turn. I have cleaned and lubed all three reels and filled the contacts. When I put a businesses card in the 2nd switch place of all three switches the problem is greatly reduced. Any tips on how to solve this?
    thanks

    1. Hi Dan.
      There are multiple possible issues that could cause this problem. Sometimes the relays switches are adjusted too close. Then, for example, the vibration of the 10 point score reel advancing can jostle the 100 point relay, causing the 100 point reel to advance.
      Other times, it can be an mis-adjustment of the switch internal to the reel that is advancing. Royal Guard is a 1968 Gottlieb. On the Gottlieb reel page, there is a discussion of the switches.
      https://homepinballrepair.com/index.php/em-score-reels-gottlieb/
      If your reel looks like the first picture (2nd and 3rd generation Gottlieb Dragon), check the adjustment of the switches and the location of the lever. Switch #3 must be far enough apart that it will not inadvertently touch. If it does, then the next reel will advance. For example, if these two contacts touch in the 10 point reel, when the 10 point reel moves at all, it will also advance the 100 point reel.
      Offhand, we are not certain which version of the Gottlieb reel your pin has. 1968 maybe first generation. Note the table further down the page. If you have a first generation Dragon reel, the proper open / close is different. That table will tell you what switches need to be open or closed, depending on the value on the reel. Insure that your switches move as required. If a switch is supposed to be open, but is so close that vibration could cause momentary closure, then this could set it off.
      Please let us know if you have any luck in figuring this out.

      1. Thanks for the tips but no luck yet. I am pretty sure I have 2nd/3rd gen but my EOS only has one switch.
        I hit a 10 point switch, the M relay goes off and both 10, 100 reel turn. The L relay does not go off, so no vibration issue.
        The problem usual starts when the sweep moves to the 1-8 position on the 10 reel and the 100 reel must be on 1-9 on the reel. In the 9 position, switch 3 closes, 0 it opens then on 1-8 it moves slightly closer. This causes the 100 reel to fire until it hits 0 then it takes a break as the 10 reel goes thru a full 1-9 rotation making the sweep close switch 3 and making it correctly fire then back to 100 firing along with 10.
        I have experimented when the 100 is misfiring i put a business card in between the 3 switch contacts on the 10 reel. It will continue to fire both reels until 10 reel sweep moves to the 0 position then the problem will stop and the 100 reel will not incorrectly fire. How is the 100 reel firing when its not getting a signal from 10’s reel 3 switch due to blocked contacts?
        Also sometimes when a 100 point switch is hit it will turn both the 100 and 10 reel or 100 and 1000 or all 3 will fire. Is it all connected?

        1. What you are describing sounds like a classic case of a mis-adjusted switch.
          There should be another switch on the reel. This stack of switches is usually visible looking through the reel itself. It is apart from the EOS switch which is located near the plunger.
          This stack has a long metal lever going into it.
          Your EOS switch is the second picture on this page. The switch stack is the first picture.
          The only reel that might not have this stack would be a reel that is by itself (such as the free game reel). The highest number (say 100,000 reel) might not have that switch, since there is not another higher reel to activate.

  4. I have a Gottlieb Batter Up. The score reel does not advance between the hundred and thousand reel. Thus if the hundred reel has a score of 800 and a five hundred point switch is hit the hundred reel will spin to 300 as it should but the thousand reel does not advance at all. Each individual reel will advance properly so a 1000 point shot will advance 1000, 5000 advances 5000, etc. I have checked the switches over and over and they are adjusted properly. There is current between the reels. Any suggestions?

    1. From your description, it sounds like the 1000 point relay is working. So the issue has to be related to the switch in the hundred point reel or the wiring.
      “I have checked the switches over and over and they are adjusted properly.”
      I would check the resistance across that switch when it is closed. Use your voltmeter. Not sure which generation of reel you have, but it looks like it is the top switch.
      Of course, one of the challenges of troubleshooting any Gottlieb pin via Internet is that the manuals are not freely available. The only Gottlieb EM we have on hand at the moment is a Play Ball. It looks like two things have to happen to advance the next reel: 1) that switch in the 100’s reel has to be closed, and 2) there is a switch in the scoring wheel on the bottom of the cabinet that has to close.
      If you are at, for example, 800 and you score 500, I assume that the scoring motor turns. That 9th position switch has to be closed. And then a switch in one of the four positions on the scoring motor has to close.
      You may want to go through, clean and adjust your switches in the scoring motor. We do not yet have a procedure for that on this website. Only for Williams (Bally is similar).

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