1952 Gottlieb Chinatown trap hole pinball machine repair: Day four

1952 Gottlieb Chinatown pinball

Day four

By the end of day three, I had a mostly working Chinatown. At the press of the start button, the game would reset properly most of the time (this would require further investigation). The next step was cleaning the playfield...

It's dirty but it works

I have to admit this is the part I dislike the most about pinball machine repair. I know a few fellow collectors that quite enjoy it. Not me. I can spend 30 hours repairing a dilapidated C title EM chasing down some fruity intermittent problem, but when it comes to detailing a playfield, I start thinking to myself. WTF am I doing this for?

Despite my dislike for playfield cleaning, I persevered...
My cleaning technique goes as follows. I start at the top of the playfield. I use a medium bristle brush and a vacuum cleaner to remove the dirt and loose material. Then I use Novus 2 on the wood and art. One pass with Novus and a soft cotton rag. When the rag gets dirty, I get another rag. Then with a dry clean soft rag I buff out the cleaned section. Repeat as necessary.

Work in progress

Section by section, I remove the posts and/or plastics. Clean and buff. I use Autosol on metal parts. I take out the metal parts and polish them on the workbench. Work my way down the playfield.  It was a pretty long process. Took me a whole afternoon. I re-lamp and re-rubber as I go. I use #51 lamps in the pop bumpers and dead bumpers. They're not as bright, but they won't interfere with the cap.

Clean Playfield. New lamps and new rubbers

Once I was done with the cleaning cleaning, I start a game... Disaster! The ball return flap solenoid locks up. The trip bank doesn't reset at all and I hear the chant of the ever cycling score motor! Poke at a few relays with a stick. No effect...Turn the game off.

This was right around dinner time. I pannick a bit. Go to my computer. Find a paper copy of the schematic for sale on ebay. Buy it. Might get it in the mail in a couple of weeks best case scenario...

Then I pause for dinner.

After dinner, I go back to the game. Have a look in the backbox. Look at the jones connectors at the bottom and find that one was half popped out unplugged. Plug it in properly and try the game again. Game starts up perfectly. It's never a bad idea to have schematics I guess!

Here are a few detail close ups

Roy Parker Art

Look at that mess of coils. Is this really the best Gottlieb could do?

Notice for high tap: Never connect the wire to high tap if line voltage is 110V or above.