Gottlieb Mars God of War (Gottlieb, 1981) New Issue

[Gr8snook09]

So today I was putting a new spring on my drop target bank and dropped a small retainer into the bottom of my machine. I had to remove the big board with the transformers and fuses, big capacitor, ground strip,etc to get the retainer. When I screwed it back down and turned on my machine to see how the drop targets would function it's just locked up and groaning...lol. Here's a link to a vid of what it's doing. Any ideas where to start ?? http://youtu.be/E8e-OXChOeE

 

[pinballdaveh]

it sounds like a connector issue. double check all the connectors in the machine not just the ones that were dis-connected. the vid sounds like some coils are locked on. on system 1 pins locked on coils is usually a missing -12v from the power supply. but i dont think system 80 has or uses a -12v. are all the output voltages from the power supply correct? it could be a slam switch problem but i never heard of a slam switch causing such a lock up problem.

 

[Gr8snook09]

When you say power supply...you mean the board up top or down below??

 

[pinballdaveh]

i was thinking of the power supply in the head. isnt the power supply in the body for the sound board. how is your power supply rebuild coming?

 

[Gr8snook09]

Power supply rebuild is done. Put it in with just J1 plugged in. Both LED's lit up (which they didn't before). Shut it down to take a whiz...came back, turned it on, no LED's. 5 and 8 vdc reading close to nothing. I checked the bridge rectifiers in the bottom and the one for the power supply was putting out close to nothing. I tested it with the multimeter set to DC. Dial on V on value of 200 and tested the rectifier with power on, black on the green ground and red on the terminal where the red, black, black wires are. Hope that was the right way to test it ??

 

[pinballdaveh]

is the F5 5A slo-blo fuse still good? do you have 12VAC coming into the bridge? has the orange filter cap C1 on the bottom board been changed yet? without the 12VDC at J1 pins 1 & 2 the 2 led's wont light. has the display problem been fixed yet?

 

[Gr8snook09]

Fuse is good, cap was changed a couple weeks ago. How do you test if there is 12vac coming into the bridge?? Haven't bothered with the displays until I get the machine to boot.

 

[Coil_Smoke]

Select an AC range on on multi-meter. Measure across ~ terminals ~ that go into the bridge for Volts AC. Full wave AC will read zero on DC scale..

 

[pinballdaveh]

on the bridge there should be markings + and - for the dc output and the other 2 lugs are the ac in lugs . set your meter for ac volts( 20 volt range or higher) and test on the 2 ac lugs. do 2 tests one with J1 plugged in and one with J1 disconnected.

 

[Gr8snook09]

Here's what I get coming out of the fuses at the bottom. F1-0, F2-6.2, F3-5.2, F4-7.9, F5-6.2, F6-18.5 and F7-109.4. This is without J1 plugged in.
With J1 plugged in I get F1-0, F2-6.6, F3-5.0, F4-7.7, F5-6.7, F6-18.4, F7-41.3

Fyi. F1 fuse is blown, so that's why it is zero.

These were with my multimeter set to V and AC at a value of 200....black on the ground strip and red on the wire coming out of each fuse.

 

[Gr8snook09]

12v tested at the bridge rectifier...11.9 AC, 12.0 DC. These are with J1 unplugged. 11.7 AC and 9.5 DC with J1 plugged in. Both LEDs lit on power supply board. All vdc at the test points are good except 5v is at 3.3 with pot turned all the way down and 4.1 with it all the way up.

 

[Gr8snook09]

Does that mean the IC chip on the power supply board is suspect ?

 

[pinballdaveh]

i have been reading the advice that you are getting from that other site. the person that told you to omit the mica insutator on Q3 and only use the thermal compound is wrong. in some cases on some transistors the insulator can be omitted but not this one. by omitting the Q3 insulator you are shorting Q3 to ground. i hope that didnt blow out some of the 5v section. put thermal compound on both sides of the mica insulator and re-install it to the transistor. after Q3 is bolted in and the 2 pins re-soldered, using your DMM set on highest resistance range , test from Q3 case to the mounting frame. infinite resistance is correct. this test is called a hi-pot or high potenial test. F1 fuse controls backbox illum. AC voltage readings are not made on black lead to ground. they are made from the secondary windings fed into the bridges.

 

[Gr8snook09]

Well got everything up and running with correct voltages. Just down to the sound problems and I don't think the knocker is working.

 

[Gr8snook09]

I officially give up for awhile. Went back to fire up the machine after eating so I could try and check z13 for shitz and gigs...the machine fired up like before...moaning with no 5v light on the power supply and not booting. I officially hate this machine. 1 step forward, 2 steps bacK.