NOTE: Due to popular demand, a plug and play solution with the custom fan and correct thread-cutting screws is now available if you don't want to bother with the DIY solution outlined in this original post below. This is available in my pinside store, Pin Monk (https://pinside.com/pinball/market/shops/1170-pin-monk) and pinmonk.com. International isn't working through pinside, so use pinmonk.com to order internationally. Otherwise, the DIY instructions to roll your own follow below. Here's what the plug n play kit looks like:
Sept 2019 UPDATE: Pinball Life is also carrying the Spike Plug n Play Quiet Fan kit now:
UPDATE 8-27-19: Working on a possible plug and play version for the previously-unsupported front-mounted fans.
NOTE: THIS FAN WILL NOT WORK ON WHOA NELLIE!, PABST CAN CRUSHER, PRIMUS OR ANY VERY EARLY PRO THAT HAS THE FAN ON THE FRONT OF THE POWER SUPPLY. IT IS FOR ALMOST ALL SPIKE 1 and 2 GAMES (THE LISTED MACHINES ON THE STORE SALE PAGE THAT HAVE THE FAN ON THE TOP OF THE POWER SUPPLY). IF YOU'RE NOT SURE USE THIS PICTURE TO COMPARE WITH THE POWER SUPPLY YOU HAVE:
ORIGINAL DIY VERSION POST
NOISY Stern Spike 1/2 power supplies can be quieted SUBSTANTIALLY
Stern insists on using CRAZY loud fans in their power supplies (34.6dB!) when much quieter ones (12.8dB) are available. I suggest picking up one of these from Digikey. It will be so quiet you can't hear it come on - a huge improvement over what Stern ships with. The CFM is less on this one, but I've never had a problem in a temperature-controlled location. If you have your pin outside in 90 degree heat, this is probably not a good idea. But for a house or temperature-controlled location, this is fine in my experience.
Replacement part 40mm x 40mm x 20mm - use ONLY this size fan:
(If you're concerned about airflow, this one from mouser has 30% more airflow than the one above, but is 21dB instead of 12.8dB - still less than the Stern at 34dB: https://www.digikey.com/products/en?keywords=MB40201V2-000U-A99 )
You'll need to get 2 thread cutting screws (NOT sheet metal, but they can work - look for "thread cutting" screws specifically) because the holes on this are a little bigger and the stock screws will not work to put it back in.
Stern used to have different power supplies in the Pro and Prem/LE, but it seems like they've settled on the Prem/LE type power supply for Pros, too, so this fan should work in all the recent Spike power supplies that have a small fan pointing up at the top edge of the power supply. If you have a larger fan in the middle of the PS on your older pro power supply, it's not nearly as loud, and you'll need to source a different fan.
Before you start this POWER OFF the machine and UNPLUG IT from the back of the head.
Here's the original Stern Fan:
Here's the newer, quieter fan:
This is the Stern Power Supply with the noisy fan:
Loosen (do not remove!) the two nuts on the left side of the power supply, then loosen the two on the right side of the power supply, then remove the three nuts in yellow below. Once you've done that the bottom cover will come forward and off:
Once the lower cover is off, disconnect the two revealed connectors here:
Remove the power supply by sliding it up and then pull it forward over the 4 loosened nuts. After removing the power supply, remove the two screws at the top end that hold the fan in:
Remove the 6 screws around the edge of the top side of the power supply and remove the lid, revealing the inside. The connector you need to disconnect is here pointed out here:
FAN KIT NOTE: To remove the existing fan, you need to free the wiring from the glob of white goo. If you don't have precision cutters for this task, you can get a pair for like $2 on Amazon with free shipping (or locally at Harbor Freight if you have one in your town):
Some of the fan wires are near the top of the white blob and can be pulled out gently. Others you need to cut free. If you need to cut, CUT CAREFULLY and shallow, a little at the time and test-pull after each snip or two. Don't go crazy here. And watch that white connector to the left of the blob. If you disturb that, your machine may not turn on.
DIY NOTE: If you don't want to splice this in, you can get the connector and contacts to crimp to make a factory-look with these Digikey parts:
Crimp on connectors (455-1135-1-ND) :
(Note the connector is 100% right, but I haven't tried the crimp on connectors yet - I believe they're the right ones, but waiting until I've done one where I add the connector to a naked fan might be a good idea)
Slide out the old fan, splice the connector onto the new fan (keep the color orientation the same, use shrink tubing to cover each color and a slightly larger tubing to cover both those) and re-install. NOTE THAT YOU MUST INSTALL THE FAN WITH THE LABEL FACING THE OUTSIDE OF THE CASE (NOT THE CIRCUIT BOARD) so it will vent the power supply! You'll need two new Thread Cutting screws to attach the new fan since the holes are little larger. Sheet metal screws will do in a pinch, but try to get the thread creating ones. I used these ones from Ace Hardware:
The new fan is so quiet you can't tell when it comes on, so to test my work, I leave the backglass off and put a torn off piece of paper towel over the fan so I can tell that the fan is coming on (when it blows the paper towel piece off) to make sure I did everything right before putting the backglass back on and calling the job done. Just play the game to put the power supply to work and look up every now and then to see if the paper towel has blown off. Sometimes it can take 20 minutes or even more (if the room is cool/cold) for the fan to kick on.
The amount of time before the power supply reaches the thermal threshold to turn on the fan (122 degrees) can vary WIDELY from machine to machine. Ghostbusters turns on very frequently. Games like KISS not as much. I haven't had a defective fan sent out yet, but it's why I recommend you ALWAYS do the paper towel test, even if it takes a long time before the fan comes on. That way you know everything's working as it should before you zip the machine back up.
If you want more concrete temperature data to make sure the machine is still being sufficiently cooled, you can get a Thomas Traceable 4240 Dual Temp probe thermometer. Put one probe inside the power supply and the other probe near the top of the head. It will measure and save the minimum and max temp recorded by each probe over a day or week or month or whatever time range you want. Super handy for making sure everything's working great now that the PS is essentially silent. You can pick them up used on Ebay for around $25 shipped. Highly recommended. They look like this:
All done with this project? Here's a couple other DIY guides I've made for newer Spike machines:
Are LED lights popping out of your spotlights (not just on Spike machines!)? Make sure they never fall out again:
Have a Stern machine from KISS or after with the softer wood cabinet? Reinforce it to prevent a splitting cab:
Are your Iron Maiden speakers crackling when you crank it up? Fix that with a cheap external amp:
Is your Spike machine occasionally resetting during hectic play, torpedoing your high score runs? This guide to fixing it might be for you:
Do you have a WoZ ECLE and think it's too loud in a quiet room? Replace two fans and make it almost silent:
And here are some other plug and play mods you can just buy:
Iron Maiden Light Tree Mod for colored mode lights:
Metallica F-U-E-L lights bracket:
ColorDMD gasket for Stern machines with the angled speaker panel: