Expert flipper help needed

I have a flipper problem on my BK2000 that's kicking my ass! The bottom flippers work fine, but the upper right flipper flutters and won't hold. I had an earlier EOS problem on my bottom right flipper that blew fuse F5 on the aux pwr driver board a couple of times. Here's what I've done / looked at so far:

Pwr to coil is good.
Coil ohms out fine.
Measuring across common lug to low pwr lug I get 5 ohms raising the flipper until it's fully raised. When fully raised I get 160 ohms.
Measuring across low pwr lug and high pwr lug (EOS switch) I get 0 ohms.
Put in new coil (old one was doing the same thing, and I checked diodes on old one and they were fine)
Replaced right cabinet flipper switch - continuity from flipper switch to low pwr lug on coil was 0 ohms.
Continuity from upper flipper switch (on bottom right coil) to pwr lug on upper coil was 0 ohms.
Didn't check Q67 on cpu board because I figured if the bottom two flippers were working it was ok.

What am I missing? Any help would be greatly appreciated....

Thanks,
Tslayer

#2 6 years ago

???

pinmike

Inactive member

#3 6 years ago

FNG

DumbAss

Pinside+ Frequent

Quoted from pinmike:
It would be a good idea to locate that transistor on power driver board that runs the upper flipper,The bottom flipper and the upper flipper are most likely to be on different transistors.

BK2K is System 11B. The flippers are not transistor driven but directly driven by the flipper cabinet switch closing.

#4 6 years ago

ELD

darcangeloel

Pinside member

Richmond, VA

7y 66,800 915 4

How does the board under the playfield look check the connections on that board ans make sure everything is in order. Also if memory serves that upper flipper gets power from the ganged eos on the bottom right flipper. Tug on all those wires and make sure nothing is loose. Also verify the correct things are happening to that ganged eos.

#5 6 years ago

???

pinmike

Inactive member

#6 6 years ago

JEG

tslayer71

Pinside member

Looking at the schematics, I think all the flippers use one transistor (Q67 / page 76&81 bk2000 manual) running through a relay. That's why I figured it if the bottom flippers worked it was ok. As far as the ganged EOS I just replaced that too. I checked it for coninituity and it looked good....

For the bottom flipper EOS problem I rebuilt the flipper and put in new EOS / ganged eos

#7 6 years ago

???

pinmike

Inactive member

#8 6 years ago

JEG

tslayer71

Pinside member

Well I ground the upper coil and both the bottom and top flipper move. There isn't a separate transistor for those two flippers. Can anyone tell me what transistors to check?

#9 6 years ago

???

pinmike

Inactive member

#10 6 years ago

FNG

DumbAss

Pinside+ Frequent

The schematic shows Q67 energizes the relay that enables the path to ground for the 4PDT relay (enabling the flippers).

I think darcangeloel has a very good suggestion. If the lower right flipper works but the upper right flipper has problems the power to and ground from the flipper goes through an interconnect board at the back of the lower playfield. Check the connectors and pins on that board. Possibly a cold or cracked joint on it.

#11 6 years ago

???

pinmike

Inactive member

#12 6 years ago

FNG

DumbAss

Pinside+ Frequent

Quoted from pinmike:
It would be the Auxiliary power board

There's an interconnect board at the back of the lower playfield that allows the entire upper playfield to be disconnected and removed from the cabinet. It's not the interconnect board in the back box. It's a smaller board that funnels all the wires from the lower playfield to the upper playfield.

bk2k_upper_playfield_interconnect_board (resized).jpg

#13 6 years ago

JEG

tslayer71

Pinside member

Ok thanks I'll check it. I guess I'm just confused because two things would go through the lower interconnect board - power and ground. I got coninituity from the low pwr lug to the cabinet flipper switch (ground), and it has power. Still could be connection problem at lower interconnect thought huh?

#14 6 years ago

FNG

DumbAss

Pinside+ Frequent

I'm not sure. You're asking for suggestions. Here's the thought process / logic.

You've said that the lower right flipper functions correctly but the upper right flipper does not. This would suggest that the problem is between the lower right and upper right flipper. The power for the upper right flipper comes from the lower right flipper but only when the stacked (ganged) switch closes (the EOS opens and closes the stacked switch). The power wire goes to the upper playfield through the interconnect board at the back of the lower playfield. Return from the flipper comes back out through the same board.

I don't know how continuity measures through crack/cold joints. When I spot them I usually fix them.

It can't hurt to check the board.

#15 6 years ago

JEG

tslayer71

Pinside member

Makes sense - Thanks!

#16 6 years ago

ELD

darcangeloel

Pinside member

Richmond, VA

7y 66,800 915 4

Quoted from DumbAss:
I'm not sure. You're asking for suggestions. Here's the thought process / logic.
You've said that the lower right flipper functions correctly but the upper right flipper does not. This would suggest that the problem is between the lower right and upper right flipper. The power for the upper right flipper comes from the lower right flipper but only when the stacked (ganged) switch closes (the EOS opens and closes the stacked switch). The power wire goes to the upper playfield through the interconnect board at the back of the lower playfield. Return from the flipper comes back out through the same board.
I don't know how continuity measures through crack/cold joints. When I spot them I usually fix them.
It can't hurt to check the board.

Yup this, if that right flipper is working but the top right is not and you've verified the coil and diodes on the coil to be good then you can be guaranteed it's between the wiring from the lower right flipper to the upper right flipper and that could be anywhere from those wires to the small board under the playfield to the wrong wires re-installed when you re-did the eos. I can take pictures of mine if you news to verify wgat wires go where. I've done stuff like that in the past and it drove me wild as to why it wasn't working.

#17 6 years ago

JER

Jjsmooth

Pincinnati

9y 104K 3,582 14 8

If the upper flipper is fluttering, the low voltage (hold) side of the coil may be bad.
Use continuity test on the lugs to check.

#18 6 years ago

JEG

tslayer71

Pinside member

Well when I tipped the playfield all the way up (and I didn't have 4 beers in me )I could get a good look at the switches on the lower right flipper. The ganged EOS wasn't making good contact with the flipper extended. It took about 30 mins with an ohm meter and adjustments to get the eos / ganged EOS working correctly. When it looked good I tested it out and it now works great! So it was flaky pwr through the ganged EOS. Thanks for everybody's help - appreciate it guys!

#19 6 years ago

ELD

darcangeloel

Pinside member

Richmond, VA

7y 66,800 915 4

OP
Quoted from tslayer71:
Well when I tipped the playfield all the way up (and I didn't have 4 beers in me )I could get a good look at the switches on the lower right flipper. The ganged EOS wasn't making good contact with the flipper extended. It took about 30 mins with an ohm meter and adjustments to get the eos / ganged EOS working correctly. When it looked good I tested it out and it now works great! So it was flaky pwr through the ganged EOS. Thanks for everybody's help - appreciate it guys!

Great job man! Enjoy and remember... Gimmie your money!!!

#20 6 years ago

JEG

tslayer71

Pinside member