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PINBALL MEDIC believes there is a technical difference between Refurbishing and Restoration. We think refurbishing is less extensive then a full restoration. First a refurbishing is performed. If a more detailed reconstruction is needed (playfield touch up, cabinet painting, etc.) then a restoration maybe necessary.
There are at least three distinct refurbishment levels. The three levels of refurbishment are Cosmetic, Regular/Full and perhaps an Extreme Refurbishment level. A restoration happens only after any refurbishment. See our service page for more rate information on all three levels of refurbishment Pinball Medic offers.
A cosmetic refurbishment would only get a game operational (fixing what needs repair) and clean (includes disposable game parts). A Full or Regular Refurbishment would include taking apart all of the game's mechanisms. Then cleaning and adjusting every part of the game. An Extreme Refurbishment would include manufacturing a game part or going beyond the call of duty to repair and clean a game and would stop just before a full game restoration would be needed. The Extreme level has only been done a few times where the game was in really bad condition (game covered in protective dirt a lot of soda was spilt on the playfield or the game needed LED bulbs or special ordered game replacement parts) or after other game conditions that extend the game's refurbishment time, however, did not result in a full game restoration
Pinball Medic highly recommends the Full Refurbishment level to insure the game will play for years to come and so parts with limited life spans (and maybe in need of servicing in the near future) will be addressed. However, we are aware that some customers simply can't afford the costs or the time of a full refurbishment This is why we offer the Cosmetic level of service.
All levels include the replacement of any disposable game parts like game balls playfield rubber rings however, only the full refurbishment level and above would include hard to replace parts like pop bumper trigger wafers and all light bulbs replaced with cooler running light bulbs ,etc.
The following is the minimum (full refurbishment level) that is done to every pinball that we sell or refurbish. If you are a novice, then this refurbishment doctrine should be used only as a brief description of what PINBALL MEDIC does and not as a refurbishment guide. Some steps in the refurbishment process can't be undone if done incorrectly and can destroy irreplaceable parts. Too many good playable pinballs have met their demise because of inexperience with game refurbishment/restoration. If you want to know what can go wrong, see our Coin-op Catastrophe Collection page.
Pinball Cabinet, Playfield, Backbox and Circuit Board Cleaning and Refurbishing process
1. The pinball is carefully examined for obvious damage either electrical in the case of printed circuit boards or mechanically for any burnt coils, stuck plungers, bad end of stroke switches, burned contacts/relay coils, missing parts/paint, playfield wear, etc. This is done long before power is applied to insure that no damage is done when the pinball is powered up.
2. Very valuable, sometimes irreplaceable parts are removed for long term storage. Backglasses are removed and stored in special made frames so even a dropped tool can not harm them. A broken backglass can turn an expensive pinball into a $300 parts machine.
3. The playfield is stripped of all plastics and hardware, including the pop bumpers, ramps, flippers, posts, rubbers, etc. and vacuumed out. All that was removed will be cleaned with special cleaning solutions. This step is not always done with as must attention to detail by our competitors and is one of the many reasons why we consider our games to be superior to the competition.
4. The playfield itself is now cleaned. The process we use will clean and rejuvenate the wood, paint, metal, etc. The small metal parts (screws mostly) are put in a rock tumbler or vibrator polisher using finely grounded walnut shells for a day or more if they very dirty/rusty.
5. The cabinet is thoroughly cleaned and vacuumed inside and out. A new 15 foot 3 conductor, with #14 gauge wire, power cord is added. Warning, a #16 gauge extension cord wire is what some "Jokers" may put on a game. This is not expectable as some games, especially Electromechanical pinballs can draw 15 amps or more causing the power cord to become heated.
6. Sold State (SS) and Electromechanical (EM) pinballs require different steps from this point on. Solid State (SS) will be described first and then Electromechanical (EM), a more complex process, second.
7. After refurbishing/restoration, all games are powered on and played occasionally for 24 hours to insure quality of product and workmanship.
Solid State Pinball Machines (SS)
SS1. First the power supply board is removed. This board usually can be identified by the large capacitors, heatsinked power transistors and full-wave rectifiers onboard. The power supply board usually has the most issues and can be the easiest to troubleshoot. The large (size & value) filter caps (cap=capacitor) are usually 20+ years old and are fried and dried out. Replacement or these parts are mandatory. The second weak point is the connectors on this board. Most are over-stressed and can be brown or blackened by the 10 to 20 Amp. loads placed on them. The male and female connectors will be removed and replaced. Removing just one of the pair is just inviting the same annealing and corrosion to take place again. Never use steal wool to clean contacts or any other part of a printed circuit board. They may make the board look clean but leave hazardous metal fragments debris. No spray on chemical contact clears are ever used as these will leave residues and will facilitate corrosion in the long term.
SS2. After unplugging the rest of the system boards and displays, the testing of the semiconductors on all the boards take place. The display high voltage (90 to 150 volts) section is checked and repaired if necessary. If the power supply board meets the requirements of the original specifications of the game, the board may be modified to correct any manufacture design defects. For example, older Gottliebs are infamous for having inadequate grounds from board to board, board to backplain or even internally in the form of lacking connector pins on high amperage loads. This is done on a game by game basis as different pinball systems need different modifications. Power is now applied and all voltages either inputted or outputted from the power supply board are measured for compliance. If found not to be correct the power for the game is removed and the problem corrected.
SS3. Once the power supply is rebuilt, the MPU or CPU board is inspected, again if there are large electrolytic capacitors on this board they will be replaced. If this board has brown enclosed chip sockets, they will be replaced with new mechanical style chip sockets. These brown colored sockets usually have a 90% failure rate. They were the cheapest sockets on the market at the time and hence were widely use by pinball manufactures. The brown chip sockets tend to work for about five to ten years, tarnish and stop making contact with the chip pins. PINBALL MEDIC either charges a fee for replacing these chip sockets or will refuse to fix a board with a lot of them on mail-in boards. The sound/voice boards are tested after the game is playable, at this point, they will be disconnected.
SS4. The lamp/solenoid driver board is the second weakest component of a pinball electronic control system. The power transistors (or SCRs) on this board take a beating every time a lamp or solenoid is activated, especially if the protective diode across a coil is defective. Therefore, all driver and pre-drive transistors are checked before this board is plugged into a game to check for an open or shorted transistor. Also, inter-board and other connectors are checked for corrosion and cleaned lightly with 400 to 600 grit sandpaper or replaced if found to be burned.
SS5. The MPU board is now ready for testing to take place. The MPU board (and the solenoid driver board in the the case of Williams system 6-7 boards) is now connected to the power supply board only, with all other connectors disconnected from the MPU board. This will allow the self-test mechanism and more complex tests to do their thing and will not allow the activation of displays, lights or solenoid to occur. If the board is proven to be defective, it will be put through more diagnostic tests to identify the problem, either by the use of a test ROM, logic probe or multi meter.
SS6. The bottom of the playfield is re-inspected for lose or burnt coils, bad diodes, shorted switches, open 'end of stroke' switches (if appropriate) and any other potential disasters waiting to happen to insure nothing obvious is wrong. The pinball's system boards, with the exception of the sound board(s), are reconnected in preparation for power to be applied. Power is applied to the game while watching the playfield for permanently activated solenoids, as these solenoids will burn up in about 15 seconds or less. Sometimes, a driver chip will be bad causing one or more coils to activate even though both the pre-driver and driver transistors checked OK. Power is immediately removed if this should happen. (The displays will then be plugged back in.) Be careful and check to see if the high voltage section is depleted before plugging in the displays. High voltage stored in a capacitor in the power supply board can cause very expensive display tubes/driver chips to be destroyed. The displays are tested and repaired/replaced. A final check with the built in diagnostics of the MPU board is done. The game should power up and run. The last step is to reconnect the sound card and check it for proper operation.
Electromechanical Pinball Machines (EM)
EM1. Once the initial cleaning is done, (see steps 1 through 5 above), the pinball is ready for some serious, get down and dirty, cleaning. A conundrum is created at this step with most technicians, whether to start with the relays or the score reels. Its the proverbial chicken and the egg dilemma. While the relays make the game work, the score reels can indicate a properly working game.
PINBALL MEDIC always starts with the score reels (the egg). After eons of hard use, these are usually in the most need of cleaning and repair. If you have ever started a game on an electromechanical pinball and have the game produce constant clicking sounds and not start a game, then usually score reels and/or a stepper unit is not returning to zero position. The problem most likely will be inside one or more of the score reels. This happens about 95% of the time on a pre-refurbished game. The typical score reel is composed of eight parts: the plastic score reel, a solenoid and plunger, an anti-reverse movement arm, a printed slide contact circuit board (slide contacts mounted on the plastic score reel), springs and leaf switches. All of these will have to be dissembled, cleaned and adjusted.
EM2. The typical score reel unit is held in place by either a clip or lever and sometimes a hand screw. This makes it easy to pull the whole unit out for disassembling. From now on a Williams score reel will be used to describe the cleaning process, as they are the most common of all and other score wheels can be cleaned in a similar fashion.
EM3. After removal of the score unit from it's holder, the plastic score wheel is removed from the unit and cleaned and wiped down with a soft, clean cloth using a special cleaning solution. All springs and clips are removed at this time.
EM4. After the plastic score reel has been removed, all other score reel parts can now be removed, cleaned and checked for defects. The solenoid is disassembled and every part is cleaned. This includes the coil sleeve, plunger, coil stop and mounting bracket. All small plastic parts are now cleaned. Both the slide contacts (located under the score reel) and the printed circuit board are now cleaned with a light sanding with 400 to 600 grit "wettable" sand paper. (We do not use any chemical cleaners as this will make the unit not work in the long term and can harm nearby plastic parts. "Wettable" sand paper tends to be stronger and last longer then paper backed sand paper and that's why its used here). It is then sprayed off with a bottle of air to remove the sand and grit from the sand paper.
EM5. Now that all the parts are clean, they are reassembled onto the score reel unit. Tested for proper operation by operating the coil plunger by hand and counting up the score past zero. This tests the whole unit including the springs, as springs can wear out. Springs can cause the score unit not to count all the time and sometimes not return to zero when a new game is started. These are replaced as needed.
EM6. Now for one of the most important steps, the leaf switches. The leaf switches on a typical Williams EM pinball's score reel have the following functions: one is a carry over switch. A carry over switch is closed (shorted) when the score unit reaches the number nine. If the unit is pulsed again (a score is made on the pinball game) both the score unit that is being cleaned and the next higher value score reel will be advanced by one count. This allows for smooth counting past the 9th digit of the score reels. The function of this switch can be checked by advancing the score unit to the number 9. One of the leaf switches should go from a normally open to a closed condition (opened to shorted) and then be opened back up when the score unit is advanced one position to read zero. If this switch is not adjusted correctly, the score units will not advance properly but the game should start and play. If this switch is normally closed, it can cause the next score unit to advance each time the previous score reel is pulsed. Now for the most important leaf switch on a score reel, at least from a game starting point of view. That's the "Zero position leaf switch". This switch "Tells" the pinball when the score reel has returned to zero. If all game score reels indicate they are in the "zero" position then the game will start a new game when the credit button is pressed, otherwise it will keep pulsing the score reels until they indicate zero. This explains the constant clicking sound and the fact that the game will not eject a ball and start a game when a score reel has not returned to zero upon game reset. If this leaf switch is adjusted normally closed, the game will start but the score reel will read something other then zero. The function of this switch can be shown by advancing the score unit by hand until it reads the digit 9. One of the leaf switches should be closed (carry over) and the other will be opened (zero position switch). If the score reel is advanced, the switches should reverse their states. This will indicate the opening of the carry over switch and the closing of the zero position switch. The reel should indicate a zero value (this is how you know if the plastic score reel was put on in the right position). Each switch is cleaned with a fine grit paper finger nail file, then adjusted for proper operation one at a time starting with the carry over switch and then the zero position switch. This lengthy, tedious, time consuming process is now repeated for every score reel on the game. On a four player EM game this can take as long as ten hours of work and explains why a four player game costs more to refurbish then a two or single player game does. The last digit score reel on a given player usually activates the >100,000 points light on the score board backglass and is not used for carry over. If you are curious, the slide contacts and printed circuit board traces are used for the "Match" function.
EM7. Whew, that last step was time consuming. In fact, four player EM pinballs can take hours more labor to refurbish because of all the time it takes to clean and adjust score reels. Gottleb score reels are the hardest to disassemble, Williams usually are the easiest. Now for the chicken part, the relays. Each relay is mounted with two wood screws though a rubber grommet (noise damper) holding down the relay flange. These screws will have to be removed to check and clean each and every relay one at a time. Believe it or not, the most important part of relay refurbishment is the tightening of the leaf switch mounting screws. The leaf switches use insulator wafers that can either dry out (shrink) or absorb moisture (expand) much like a 20+ year old capacitor. This moister variance causes shrinkage or expansion of the many hundreds of wafers used in a typical pinball game. A well known phenomenon occurs occasionally, a perfectly working and refurbished game may not work when it is delivered to a customer. When the game was worked on, the humidity was low and the wafers shrank. When the pinball was delivered to the customer, it was placed in a humid area. The wafers expanded pushing the switch contacts apart misaligning some relay or other playfield contacts. This is not the fault of the technician who worked on the game. This is one of the only problems that can actually be blamed on the weather. Fortunately, most contacts will stay adjusted, only a few will have to be corrected.
This is why PINBALL MEDIC recommends we deliver and install a game so we can make these final adjustments. For the extra fees involved in delivery services, it is well worth the additional cost. Usually, after this final adjustment, the pinball will settle into it's new surroundings and work trouble free for many years to come.
EM8. Now after the pinball has been checked to see if it has a screw loose. The contacts are checked to see if they need adjustment by hand actuating the relay. If light (or by use of an Ohm meter) can be seen though a set of contacts that are supposed to be closed then the nonmoving contact is adjusted to rectify this condition. The contacts are then lightly cleaned with a business card folded in half and readjusted if necessary. Every relay will get this same treatment as well as the playfield switches. Oil or contact cleaner is never used as these cause more problems then they solve. See our Tech Question 14 on greasing EM game parts for more information.
EM9. The index cam motor and leaf switches are next. This can be a very tricky unit to adjust as these leaf switch banks are very complex and have a lot of moving parts (cams). They are treated much like the relays are except the leaf switch banks are seldom removed as this can easily cause switch misalignment. Tighten the mounting screws, lightly file the contacts, oil the motor by unscrewing the whole unit and placing (just) three drops of 3 an 1 (general purpose oil) into the small hole on the side of the motor (should be a piece of felt under this hole). Do not oil anything else as this will only serve to gum up the works later. Remember that oil/grease is just as bad for plastic parts as putting water on the playfield.
EM10. Stepper units can be thought of as large, sometimes more complex, score reels. Some can step up or down, some can single step in only one direction. The difference is the addition of just a few more parts and springs. This just makes life more interesting. The refurbishment process is the same. The unit is taken apart, the solenoids cleaned, slide contacts and boards sanded, tension springs checked and adjusted/replaced, etc.
EM11. The playfield components are now looked after in the same way as above. The hardest working units (pop bumpers, slingshots, outhole solenoids, flipper units, etc.) are all fully taken apart and cleaned or replaced, if necessary. The pop bumpers get new "trigger wafers" and the flipper units all get new "end of stroke" switches and coil sleeves, coil stops and if bad enough, complete rebuild kits. Note: metal coil sleeves should be replaced by plastic ones as the metal coil sleeves are obsolete and do not work as well as plastic ones do. They have even been known to "eat" a coil plunger from time to time. All other units are taken apart and cleaned and checked for proper operation. All playfield contacts are now adjusted to factory specifications.
EM12. In short, All units, score reels, relays, index cams switches, coils, motors, playfield toys, etc. have been taken apart, cleaned, adjusted, replaced if necessary inside and out on every pinball Pinball Medic sells. Now it's time to put the EM pinball game back into proper working order. This is when the ZEN of EM pinball refurbishment comes into play. A Electromechanical pinball is more like a living entity then an amusement device. It will complain in a whisper if something is amiss. The game almost talks to you.
With the severe shortage of Electromechanical pinball game schematics (the games are 20+ years old and are seldom sold to third parties with documentation), operator upkeep and complexity of operation, most Electromechanical pinball machines have a lot to complain about.
Even when all their components have been thoroughly gone through, the game might not function up to par. That's when the highly experienced technicians we have at PINBALL MEDIC shine through. They can diagnose any random problems and adjust/replace what's wrong.
Only after a refurbishment is complete, if any major rebuilding operation is needed to bring a game up to our high playability and appearance standards, a restoration process will now occur. This may require taking the cabinet apart to replace a bad backboard, extensive backbox repair and other carpentry related activity or art repair/replacement .
Coin doors are sometimes scratched, rusty, dented and have to be replaced / reconditioned. Playfields can be perfect except for small nicks in artwork or are in need of some post hole repair or playfield plastics may be broken and in need of replacement. The customer may request a playfield clear coat to protect both the playfield and the cosmetic touch ups. All of these restorations are very time and labor intensive and can add as much as twenty hours to a pinball's resurrection. Also, some pinball purest consider a complete restoration a win-lose proposition as they can make the game less then original (in mint condition).
After a complete restoration, the game will look and play like new, but the game's value to other pinheads (a term used affectingly to refer to pinball enthusiasts) could be somewhat reduced. PINBALL MEDIC tries to strike a balance between game cosmetics / playability and doing anything that would greatly reduce the value of the game. Coin doors, pinball legs, playfield apron artwork, if not in excellent condition will be replaced with ones that are. This we feel does not devalue the game appreciatively. Side-art, massive playfield touch ups, backglass touch ups, can, and will be done only if the customer desires it and if economically feasible. Nothing will be done to a game if it does not increase a game's resell value or playability.