Time Machine
Data East, 1988I was getting started on disconnecting the connectors from the playfield so I could do flipper rebuilds and VUK tune-up, when I saw the white powder on the resistors on the PBB!
Is this just age, or does it suggest a different underlying problem ?
Is it important to replace them, and would any deterioration be likely to cause gameplay issues?
Thanks for any help.
John
PBB data e (resized).jpgLooks like the cement is breaking down and dropping onto the resistors below. I've never seen that before. Usually they don't go bad.
Those are cement resistors that are starting to crumble. You could have them easily replaced by Chris Hibler @chrishibler.
Quoted from Crash:Looks like the cement is breaking down and dropping onto the resistors below. I've never seen that before. Usually they don't go bad.
This can happen if machine spends time in a basement with high humidity.
-Mike
Quoted from pintechev:Those are cement resistors that are starting to crumble.
I'm probably just confident enough with a soldering iron to be dangerous! and have a go at replacing them myself. Presumably the cement resistor has some properties such that I need to replace like with like, rather than just looking at any resistor with equivalent resistance & wattage ?
How important to replace them quickly ? My quick maintenance of the flippers might have just turned into something bigger.
I would vacuum off the mess and change them out within the next month before a real issue starts.
-Mike
I’ve never seen that before. That material is part of the thermal design of the wire wound sand resistor.
Easy replacement.
Clip the leads close to the board.
Heat the leg from the solder side and gently extract it.
Clean up the hole in your favorite way.
Install new part leaving plenty of air gap between the part and the board.
Clip the left over leg =outside= of the solder meniscus (the solder volcano).
Have a beer and marvel at your handiwork.
—
Chris Hibler - CARGPB #31
http://ChrisHiblerPinball.com/contact/
http://www.PinWiki.com - The new place for pinball repair info
Quoted from ChrisHibler:Easy replacement.
Clip the leads close to the board.
Heat the leg from the solder side and gently extract it.
Clean up the hole in your favorite way.
Install new part leaving plenty of air gap between the part and the board.
Clip the left over leg =outside= of the solder meniscus (the solder volcano).
Have a beer and marvel at your handiwork.
Thanks Chris. How important is the resistance? I am about to order some replacements, and I see that on my board the resistors are 5ohm and most of the other images I see online, they are 3ohm.
The local supplier doesn't have 5ohm, but has lots of other specs - 2.7, 3.3 .... etc with 4.7ohm and 5.6ohm the closest to what is currently on the board.
Otherwise it is ordering from China 
Quoted from altan:It's snowing.
Quoted from jaybeedee:Thanks Chris. How important is the resistance? I am about to order some replacements, and I see that on my board the resistors are 5ohm and most of the other images I see online, they are 3ohm.
The local supplier doesn't have 5ohm, but has lots of other specs - 2.7, 3.3 .... etc with 4.7ohm and 5.6ohm the closest to what is currently on the board.
Otherwise it is ordering from China
Yes...5 ohm are a bit scarce these days. I can't say why DE settled on that value, but 4.7ohm is a good replacement.
Those are current limiting resistors for the flash lamp side of the function.
--
Chris Hibler - CARGPB #31
http://ChrisHiblerPinball.com/contact
http://www.PinWiki.com - The Place to go for Pinball Repair Info
I know I'm no one to contradict CH, but if I were you I'd just vac the mess and not worry about it. Maybe check occasionally in case the deterioration accelerates.
They're for flashers, so low duty cycle. The ones that are snowing don't look like they've overheated. Worst case, resistor opens and flasher stops flashing.
If it ain't broke...
Still, it'd be an easy repair to get your feet wet with on board work, I suppose.
Wanna join the discussion? Please sign in to reply to this topic.
Great to see you're enjoying Pinside! Did you know Pinside is able to run without any 3rd-party banners or ads, thanks to the support from our visitors? Please consider a donation to Pinside and get anext to your username to show for it! Or better yet, subscribe to Pinside+!
This page was printed from https://pinside.com/pinball/forum/topic/ppb-board-i-m-guessing-this-white-powder-shouldn-t-be-here?hl=jdissen87 and we tried optimising it for printing. Some page elements may have been deliberately hidden.
Scan the QR code on the left to jump to the URL this document was printed from.
Auckland
Chesterfield, MO