(Topic ID: 172300)

Jacks open. Going to need help.


By Arcade

3 years ago



Topic Stats

  • 15 posts
  • 3 Pinsiders participating
  • Latest reply 3 years ago by MrBally
  • Topic is favorited by 2 Pinsiders

You

Linked Games

Topic Gallery

There have been 3 images uploaded to this topic. (View topic image gallery).

Jacks1 (resized).jpg
IMG_3128 (resized).JPG
IMG_3126 (resized).JPG

#1 3 years ago

Just picked up a fairly nice Gottlieb Jacks Open Wedge head.
Overall it is in good shape but is going to require some switch help to get it up and running.
So far I have gone through the game and cleaned all the Jones plugs male and female.
I have gone through the stepper units and made sure the contacts are clean and the units are stepping properly and smoothly.
99% of EM's that I have fixed up will have the big round motor in the bottom of the cabinet turn non stop while trying to reset the score reels to zero. Which I can fix fairly easy.

But this one just seems pretty dead at the gate. lol
When powered up the backbox lights up and shows Tilt like it should.
The only relay that stuck on was the "P-Target Bank reset relay".
So I reset the target bank manually and that stopped.
Now when I power up the game the only thing trying to move oddly enough is the "Total Play Meter" that counts the games played.
It is humming like crazy, but nothing else in the game is even trying to move.
The playfield lights will come on if I hold in the H Hold relay.

What should I try first?

#2 3 years ago

With power on, start to turn the score motor assembly. Does it the rotate by itself to the next "home" position(120°)?

If not, figure out why and correct. The Score Motor service plug could be unplugged.

#3 3 years ago
Quoted from MrBally:

With power on, start to turn the score motor assembly. Does it the rotate by itself to the next "home" position(120°)?
If not, figure out why and correct. The Score Motor service plug could be unplugged.

Thanks I know for a fact the motor does not turn by itself.
The little Jones plug is in he correct slot.

#4 3 years ago

It sounds like your score motor is broken. The humming may be the sound of the motor being stuck and unable to turn. Sometimes the cam is stuck due to a switch stack problem, and sometimes there is foreign material jamming the motor gear train, but most often one of the bearings in the gear train has worn out and that is causing the problem.

It's worth your time to carefully look at the motor rotor and gears to see if anything is jamming up the works. If it turns out to be a bad bearing in the gear train, then you'll need to replace the motor. It is possible (sometimes) to repair these types of motor, but that's a non-trivial job.

- TimMe

#5 3 years ago

Trace voltage to motor ( be sure the run-on switch is closed) if voltage is present and the motor does not run, replace the motor. If no voltage present, correct the situation. Use standard electrical troubleshooting techniques.

#6 3 years ago
Quoted from MrBally:

Trace voltage to motor ( be sure the run-on switch is closed) if voltage is present and the motor does not run, replace the motor. If no voltage present, correct the situation. Use standard electrical troubleshooting techniques.

Thanks. What should voltage be at the motor?
Thanks for the help guys.
Much appreciated.

#7 3 years ago

Went and measured Voltage.
I did not know whether to use AC or DC but since I got nothing on DC here are my AC readings.
At the motor I am getting 8 volts
On the lugs of the Power supply I am getting 5 volts, 3 volts and 18 volts.

I did check and the item that is humming is indeed the Total play Meter. It is not the score motor.
Nothing is jamming the gears and they move smoothly by hand.

Not sure which switch is the always run switch. But the switch at the top right of my photo is just a single blade so it may be broken if that is it.

Here are photos of my score motor and power supply in case anyone can spot anything.

IMG_3126 (resized).JPG

IMG_3128 (resized).JPG

#8 3 years ago

The top right "switch" on the score motor is the motor brake. It looks like a switch, but it's just an anti-coasting spring to stop the cam from coasting past the home position. It only has one blade.

All voltages are AC. You should be getting something very close to 25 volts at the transformer for the coil power. You must measure between the black wire and the red wire at the transformer lugs to check for this voltage. If you really are only getting 18 VAC output at the transformer, you'll need to fix that first.

8 volts at the motor is way too low. The motor needs 25 VAC to run. Assuming your transformer output is good, if the motor voltage is still too low try cleaning the switch contacts at the motor 1C position. You may have a dirty motor run-out switch. The motor 1C position is the switch stack at the bottom of your pic in post #7. It's the second stack from the top.

- TimMe

#9 3 years ago
Quoted from TimMe:

The top right "switch" on the score motor is the motor brake. It looks like a switch, but it's just an anti-coasting spring to stop the cam from coasting past the home position. It only has one blade.
All voltages are AC. You should be getting something very close to 25 volts at the transformer for the coil power. You must measure between the black wire and the red wire at the transformer lugs to check for this voltage. If you really are only getting 18 VAC output at the transformer, you'll need to fix that first.
8 volts at the motor is way too low. The motor needs 25 VAC to run. Assuming your transformer output is good, if the motor voltage is still too low try cleaning the switch contacts at the motor 1C position. You may have a dirty motor run-out switch. The motor 1C position is the switch stack at the bottom of your pic in post #7. It's the second stack from the top.
- TimMe

Great info Tim.
I will do that tomorrow.
I was measuring voltage by using the ground wire at the bottom of the power supply.
I did not do the black and red wires on the lugs but I will.
I measured voltage at the score motor by using the same ground wire and putting the other end on each lug of the motor.

#10 3 years ago

OK, your transformer is probably good then. EM games don't have a system ground plane like solid state equipment, so you can't measure voltages that way. The closest thing to a "ground" on an EM is the black return wire for the coils. There is also a different (separate) return wire for the lamps, which may be a bare bus wire (on the underside of the PF) or a black/white wire.

On GTB EMs, the supply rail outputs of the transformer come from two completely separate sets of windings. They are not electrically connected in any way, and should never be connected. One output winding is for the coils, at 25 VAC. The other output winding is for the lamps, at 6 VAC.

On your transformer, as already noted the lugs with the black and red wires are the 25 VAC output winding.

The 6 VAC output winding has one lug in front with the black/white wire attached to it, and one lug in back with the white wire attached to it.

- TimMe

#11 3 years ago

Also, the lugs at the bottom of the transformer are the INPUT power and are at 115 VAC, so you want to stay away from those. The bottom lugs also use red and white wires, but you'll notice that those wires have plastic insulation, rather than the cloth insulated wires used for the low-voltage outputs.

You should always assume any wires inside your game that have plastic insulation are at 115 (lethal) voltage.

- TimMe

#12 3 years ago

Thanks Tim.
Yes, I wish to stay away from high voltage at all cost .
What is the best way to measure voltage on the two lug score wheel motor?

#13 3 years ago

Clip a meter lead to each of the motor solder lugs. Using your finger, manually push in the actuator of any relay that turns on the motor - the W relay is always a reliable choice. Read the voltage while the motor is running.

- TimMe

#14 3 years ago

OK. Food for thought.

Today I cleaned the stack contacts. No luck.
I also measured voltage at power supply from black top wire to red top wire. Getting 30 Volts.
Measured voltage at score reel motor while turning by hand. Motor never kicks in and I only get 3 volts while turning.

Now the strange part. The Total play meter is still humming like crazy.
So I decided to check voltage at the two screws it is attached to on the bottom, circled in red in the photo.
I am getting a solid 22 volts. (This just seems wrong)
But looking over the wiring I can't figure out why the play meter is getting more volts them my score reel motor.

Jacks1 (resized).jpg

New info. I can move the total play meter one step at a time by separating the tilt switch on the coin door. Every time I make and unmake tilt switch contact it moves one total play.

#15 3 years ago

You need to trace the wiring to the score motor and figure out the break/dirty contacts/corroded connection causing the low AC voltage. Use the proper wiring diagram and standard electrical troubleshooting techniques or ask someone local to come out to the machine to show you how to do.

Promoted items from the Pinside Marketplace
From: $ 18.00
Apparel - Men
Pinside Shop
$ 4.00
Playfield - Decals
UpKick Pinball
$ 10.00
Cabinet Parts
Flashinstinct
$ 20.00
Various Novelties
GC Pinball
$ 84.95
Cabinet - Shooter Rods
Super Skill Shot Shop
$ 22.00
Cabinet - Sound/Speakers
ModFather Pinball Mods
$ 64.99
$ 74.99
Playfield - Plastics
Pin Monk
From: $ 9.00
Electronics
nvram.weebly.com
From: $ 44.95
Playfield - Toys/Add-ons
PinBoss Mods
$ 98.00
Playfield - Other
ModFather Pinball Mods
$ 115.00
Playfield - Toys/Add-ons
ModFather Pinball Mods
$ 208.87
$ 229.99
Lighting - Other
Lighted Pinball Mods
$ 40.99
Lighting - Interactive
Lee's Parts
€ 60.00
Playfield - Toys/Add-ons
YOYOKOPTER MODS
$ 5,899.00
Pinball Machine
Operation Pinball
$ 134.99
Playfield - Plastics
Lighted Pinball Mods
$ 229.99
Lighting - Led
PinballBulbs
$ 3.00
Playfield - Decals
Doc's Pinball Shop
$ 34.95
Playfield - Plastics
Hookedonpinball.com

Hey there! Got a moment?

Great to see you're enjoying Pinside! Did you know Pinside is able to run thanks to donations from our visitors? Please donate to Pinside, support the site and get anext to your username to show for it! Donate to Pinside