(Topic ID: 312151)

1976 Gottlieb Ship Ahoy Add A Ball Scoring Problem

By JeffreyK

2 years ago

Topic Heartbeat

Topic Stats

  • 17 posts
  • 3 Pinsiders participating
  • Latest reply 2 years ago by JeffreyK
  • Topic is favorited by 1 Pinsider


Linked Games

Topic Gallery

View topic image gallery

ShipAhoyMotorSwitch2TopSm (resized).jpg
ShipAhoyMotorSwitch2SideSm (resized).jpg
Ship Ahoy D relay (resized).jpg
SA6 (resized).jpg
#1 2 years ago

My Gottlieb Ship Ahoy Add A Ball EM has eleven rollover switches that awards 5000 points when lit or 500 when not lit, two alternating targets that does the same, and two pop bumpers that awards 500 points, all of which are randomly but increasingly awarding 1x, 2x, 3x or 4x but not 5x the base number of points. I recently disassembled the scoring reels for cleaning to resolve ongoing issues with them not resetting to zero. I believe the 5x award process is performed by the motor, which I have not yet touched. Can someone suggest what to look at and hopefully recommend a diagnostic process? I do have the schematic, but still a novice at understanding the more advanced operation logic.


#2 2 years ago

When you say 3x for example, do you mean that you might get 1500 points instead of 500 points? If so it may be that the 500 point relay is not releasing at the end of the 1st Score Motor cycle as it should. Usually a 500 (or 5000) point relay fires when a target (or rollover) switch closes and holds itself on after the target switch opens while the Score Motor runs through a 120 degree turn. Near the end of that cycle a motor 2B switch opens which lets the 500 point relay relax.

Watch what your 500 (or 5000) point relay does when the game misbehaves. Does it let go after 500 points or does it stay active for more points? If it doesn't let go after one Score Motor cycle you'll need to sort out why.

An example of this circuit is animated and explained in more detail at:


#3 2 years ago

Thanks for the reply Mark, sorry that I did not properly describe the problem. By 1x - 4x, I meant that it is randomly awarding 100 - 400 points when it should be 500, or 1000 - 4000 points when it should be 5000. It is happening about once every ten times that points are a multiple of 5, even more often during faster play and points scoring. It is much rarer to miss a single 10, 100 or 1000 point award. Another new oddity, perhaps related, is that as an Add A Ball machine, when all the rollover switches are lit, it is supposed to award an extra ball (Wow) when the #1 or alternating #10/#11 rollover switch activates, but now sometimes awards multiple extra balls (Wows) instead of one. As I mentioned, I recently disassembled to clean the 10, 100 and 1000 (but not 10000) scoring reels to resolve the issue of them not returning to zero with the machine continuously trying to reset. Thanks, Jeff.

#4 2 years ago

500 or 5000 points are usually scored by a switch on the Score Motor at position 1A which closes 5 times each time the Score Motor rotates through 1/3 of a turn, or a Score Motor cycle. The closing switch sends 5 pulses to the 100 or 1000 point relay which in turn sends 5 pulses to the appropriate Score Reel. The point relays send 5 pulses to the chimes too.

Dropping one or more of the 5 pulses often means that the Score Reel can't keep up because of a mechanical restriction or friction of some kind. A few experiments you might try:
- Listen to the chime. If the chime sounds 5 times while the Score Reel advances fewer than 5 positions the point relay is probably working properly.
- Jumper a reliable Score Reel coil to an unreliable one by connecting the non-black wires on the Score Reel coils together. Then score 500 or 5000 points so both score reels advance at the same time. (Avoid rolling over from 9 to 0 to avoid unnecessary complications.) If either one reliably advances 5 positions the driving circuit is likely fine and the problem is likely a mechanical issue in the unreliable Score Reel.

#5 2 years ago

Hi Mark,

I believe that the chime sounds the same number of times that the 100 or 1000 score points advances, which is usually once or twice, as opposed to three or four, whenever it is less than the five it is supposed to be.

I opened the machine with the playfield on the prop rod to watch the motor spin while manually tripping the 5000 / 500 point rollover switches and 500 point bumpers on the playfield. The motor always appeared to move 120 degrees and I could not recreate the issue, no matter how fast I hit the switches. I dropped the playfield and played a few games without the glass on, and it missed points a couple of times. I replaced the glass and within a half hour, it returned to missing points during every game.

I am not sure what to consider a reliable score reel, the problem currently exists on both the 1000 and 100 score wheels and unsure of the 10 score wheel as nothing awards 50 points. When I got the machine, I think it was scoring correctly, but performing very long reset cycles often getting stuck at 8000. I disassembled the 1000 score reel, cleaned out a lot of crud and very lightly greased all of the moving parts except the coil plunger with Super Lube Teflon Multi Purpose grease. This reduced the stuck at 8000 issue but did not completely eliminate it, so I disassembled and cleaned the 1000 score reel again, this time using that grease only on the contact surface of the lever that activates the switch at the 8 to 9 position rides on the side of the score reel, leaving all other plastic to plastic and plastic to metal friction surfaces unlubricated. After a week of the 1000 score wheel working perfectly, I performed the same maintenance on the 100 and 10 score wheels with minimal lubrication. I have not yet cleaned the 10000 score wheel as it is the only one with a PCB board, and after reviewing the maintenance process online, chose to put it off until I obtain the recommended Pinball Resource Contact Disc grease. As I learned long ago to suspect a new problem on the last thing(s) I serviced, I am unsure if my rebuilding the three score wheels has caused this.


#6 2 years ago

If the chime and score reel fire the same number of times that implies that they're getting the same number of pulses. That in turn would imply that the 100 and 1000 point relays that drive them aren't pulsing 5 times. You could watch the relays and see if they reliably pulse 5 times when scoring 500 or 5000 points.

If the point relays don't always pulse 5 times then the score reels and the point relays are the victims, not the culprits. When scoring 500 or 5000 points the point relays are probably driven by a Score Motor switch at position 1A. You might have a close look at that switch to see if it's closing reliably, if it's damaged or loose or dirty or maybe has a loose contact at the end of the switch blade.

#7 2 years ago

Hi Mark, from the schematic, the D relay is for 500 points and the E relay is for 5000 points. As the problem is mostly about getting 1 or 2 hundred instead of 5 hundred points, I removed the D relay, examined and lightly cleaned its switches. I believe I also examined and lightly cleaned the 1A motor switches. Neither resolved the problem. When I observed the operation with the machine open, I saw that the D relay stays activated throughout the 120 degree motor rotation when awarding 500 points, but deactivates earlier in the motor rotation when awarding less than 500 points, a lot earlier when awarding only 100 points. Can you tell from the schematic what I should examine that may be allowing the D relay to deactivate prior to the motor completing its cycle? Thanks, Jeff.

#8 2 years ago

Meant to add this to my post ....

SA6 (resized).jpgSA6 (resized).jpg
#9 2 years ago
Quoted from JeffreyK:

When I observed the operation with the machine open, I saw that the D relay stays activated throughout the 120 degree motor rotation when awarding 500 points, but deactivates earlier in the motor rotation when awarding less than 500 points, a lot earlier when awarding only 100 points.

Excellent observation. The D and E relays should both hold themselves on, once activated, through their own lock in switches and the Motor 2B switch in the red box until 5 scoring pulses reach the score reels. The Motor 2B switch then opens after the 5 scoring pulses to let the D and/or E relay relax. If the Motor 2B switch opens early you'd only get the points scored before the D or E relay relaxed.
Ship Ahoy D relay (resized).jpgShip Ahoy D relay (resized).jpg
Check the Motor 2B switch. Its switch stack could be loose, a contact could be loose, it could be dirty, it might need more tension, etc.

#10 2 years ago

Hi Mark, while the 2B NC motor switch certainly appears to be the common element and most likely culprit on the schematic, I find it hard to imagine that once it is closed and the D or E relay activates, what could possibly open that switch before it encounters the B level cam pin? I watched some YouTube EM motor videos from Pinball Garage and Goats Head that identifies switch positions and describes operation, but offers little about how to effectively service switches in the A or B level that are blocked by the C level cam plate or C and D/E level switch banks. I tried to slip a file between the 2C switch arms to lightly file the 2B contacts, but not really sure that I got to them and the scoring problem continues to occur. As I said, I have not yet worked on the motor assembly and somewhat apprehensive about doing it correctly. Can I remove the front 2C screw and loosen the rear 2C screw to rotate that switch bank up to expose the 2B switch bank, similar to the Goats Head video showing how he modified the dog switch position? If not, should the 2C switch bank be completely removed, or can you offer any other suggestions for observing and servicing the 2B switch bank? Thanks, Jeff.

ShipAhoyMotorSwitch2SideSm (resized).jpgShipAhoyMotorSwitch2SideSm (resized).jpgShipAhoyMotorSwitch2TopSm (resized).jpgShipAhoyMotorSwitch2TopSm (resized).jpg
#11 2 years ago

You could do some more experimentation to support or disprove the theory that the 2B switch sometimes opens early before taking things apart. The switch serves the same purpose for the D, E and U relays. You could try manually closing two or more of them together to see if they relax simultaneously. If they don't all release at the same time the 2B switch may not be the issue.

You could also try jumpering across the 2B switch (yellow-black wire probably to red-white wire) with an alligator clip test lead which would effectively prevent it from opening. If the relays never release prematurely the 2B would be the likely culprit. Note that they may never release until you remove the test lead.

The suspected fault isn't that the switch activates spontaneously before the score motor post activates the 2B switch stack. It may however chatter or vibrate as the motor turns just enough for the contacts to disengage momentarily which would be enough to drop out the relays. The same might be happening to the lock in switches on each relay, but since it happens to multiple relays 2B is more likely.

3 weeks later
#12 2 years ago

Hi Mark,

I ended up removing the motor assembly from the C bracket to get the best access and lightly cleaned the 2B switch by passing the file though the 2C switch blades (the plastic switch lifters blocked side access to the 2B switches). I also tightened the 2B switch stack screws slightly, put a few drops of light oil in the motor oil port and manually spun the motor to observe the switches operate. The frequency of the problem has been reduced by about 90 percent, which I will live with unless it gets worse again.

Thanks again for your help,

4 weeks later
#13 2 years ago

With the scoring problem getting much worse since my last post, I removed the motor 2C switch to access the 2B switch. I emery cleaned the contacts on both the 2B and 2C switches, checked the position of the adjustable switch dog and manually rotated the motor counter clockwise to visually confirm the 2B and 2C switches open and close correctly, but the problem continues so either I missed it or it lies elsewhere. When the 5x scoring works correctly, the D/E (500/5000) relay stays energized and the motor 1A third (Scoring) switch arcs 5 times while opening and closing on the 5 teeth of the 1/3 motor A plate rotation. When the 5x scoring ends prematurely, the D/E relay releases early and the motor 1A third (Scoring) switch does not arc while opening and closing. Can someone suggest anything else I can do to try to locate the problem? Thanks, Jeff.

#14 2 years ago

I'd also check out the M and L relays - they're the ones doing most of the work, pulsing on and off five times in a closed loop with the EOS reel switches...

Switches clean and gapped? Are the armatures clean and moving freely? Armatures not magnetized? Score reel EOS switches look good?

#15 2 years ago

Thanks for those suggestions. I am very new to this and learning as I go. My Ship Ahoy was mostly working when I bought it, but well used and developed quite a few problems since, most of which I have resolved with equal parts of Pinside support and luck.

I had not heard about a magnetized armature before, so just becoming familiar now by reading associated posts. I may have previously run into one unknowingly when the armature of the AS stepper relay that rotates the anchor lights and alternating green 500/5000 score light stopped advancing the ratchet and after a cleaning did not fix, I tightened the armature spring to get working. From what I read, a magnetized armature can be diagnosed by it not returning to its home position with the machine powered off or by removing it and seeing if a small metal object like a pin sticks to it? It is also my understanding that replacement armatures for EM Gottliebs are mostly unavailable and demagnetizing remedies include a light hammering, freezing, buffing, touching it with a soldering iron or an electric degausser?

I included a schematic, contact adjuster, file and emery stick on my first PB Resource order, so have worked at lightly cleaning any switches I think may be a problem. I am unsure in terms of proper gapping, relying more on watching motor and relay switches work, checking them manually with the power off to observe their movement and contact and sometimes testing them for conductivity. Not long after I got the machine, three of the four score reels were getting stuck on 8 and preventing a reset, so I took them apart, cleaned and reassembled them with no issues since. I did clean the EOS (End of Stroke?) switch contacts and saw them open and close, but again had no concept of adjusting the switch gap.

I have not yet looked at the M and L relays, so will do at my next opportunity and report back.


#16 2 years ago

A good reference for switch cleaning and proper gapping:


In short, when a switch closes, you want the long blade to move the short blade a small amount, causing the two contacts to "wipe" across each other. Clay describes it fully in the reference above.

1 week later
#17 2 years ago

Just to wrap this up, DaMoib graciously took this up off line with me and patiently guided me through the fine art of safely jumpering around groups of switches to isolate the problem, which turned out to be a dirty and misadjusted ball 6 switch in the ball count unit that I did not know was behind the stepper. As a bonus, I also found two permanently open stepper EOS switches, switch stacks with screws missing and a couple more questionable switches. My thanks to all who helped me resolve this issue, Jeff.

Promoted items from Pinside Marketplace and Pinside Shops!
From: $ 1.25
Playfield - Other
Rocket City Pinball
$ 1.00
Pinball Machine
Pinball Alley
Hey modders!
Your shop name here


Wanna join the discussion? Please sign in to reply to this topic.

Hey there! Welcome to Pinside!

Donate to Pinside

Great to see you're enjoying Pinside! Did you know Pinside is able to run without any 3rd-party banners or ads, thanks to the support from our visitors? Please consider a donation to Pinside and get anext to your username to show for it! Or better yet, subscribe to Pinside+!

This page was printed from https://pinside.com/pinball/forum/topic/1976-gottlieb-ship-ahoy-add-a-ball-scoring-problem and we tried optimising it for printing. Some page elements may have been deliberately hidden.

Scan the QR code on the left to jump to the URL this document was printed from.