I've never been real happy with the performance of the bumpers on my Atlantis. My first attempt to pep them up was taking some turns off the coil and high tapping the game. Still wasn't happy.

I had some yellow dot coils I'd ordered before. Last night I installed them and put the game back on normal tap. The bumper performance is now where I want it, but it appears to me it has caused a different issue.

When you hit the Targets On star rollover, it energizes the P relay which is then held on through a lock in switch on P and also the n/c switch on the Targets Off star rollover. The targets stay lit until the Targets Off star rollover n/c switch is opened, and the target lights go out and scoring is 500 instead of 3000 and an advance on a lit standup target.

My problem is as soon as a bumper hit happens, with the P relay energized and the target lit, the P drops out. I've checked the lock in switch and the n/c switch on the star rollover. All is good. Hitting any other target on the game, slings, drops, rollovers, other standup targets, does not cause P to drop out. Only a bumper hit.

Atlantis has the two bumpers fired via one relay so when you hit one bumper, you get both. Obviously those yellow dots are very low resistance coils. The only thing I can come up with is between the two yellow dot coils and the bumper relay coils all firing, it's pulling so much power that the locked on P relay, an A-9740, just doesn't have the power to hold on. According to Clay's guides, the 9740 specs out at 24 ohms. Mine is at 27 ohms so just a bit weaker.

Anyone have any other ideas? I'm thinking maybe orange dots maybe be a better solution here. And to answer what I know is coming, the bumpers are rebuilt completely and work very smoothly. Just not enough power with the setup I had before this.

Sorry about the confusion. I meant the P lock in switch and the n/c switch on the Targets Off rollover switch are adjusted properly.

I will do the pounding test. The P coil is high resistance since it will stay locked on for longer periods. Not like a hold relay but it does stay on long enough that it gets warm.

I'm a proponent of the idea that when you mess with something and then tit doesn't work, go back to what you messed with. Those bumper coils are the only change.

I like to keep them as original as I can. I also like them to play well. So there's always a tradeoff. I try to do modifications that are easily reversed if someone doesn't like them. Minimal stuff like this, colored legs etc. I don't generally change out target faces or drop targets, or plastics, or that kind of stuff.

No suspicious behavior when the drops reset.

OK, so I did the pound on the playfield test. Nothing. Targets remained lit. That pretty well rules out vibration as a source of the issue.

I neglected to mention that I had installed these coils once before and I think at that time the game was high tapped. I can't remember if it was causing the lock relay to drop or the solenoid fuse to blow, but it was one or the other. I removed them and reinstalled the original coils and the problem ceased.

I figured that if I removed the high tap that might stop that problem and it did, but only to have this problem crop up. I'm pretty sure that the between the two coils for the bumpers and the relay coil pulling voltage, it's causing the P relay, which is not an overly strong relay to start with, to lose enough voltage where it just drops out.

I thought Steve Young sells orange dot coils for bumpers but he does not, only yellow dots. The flippers come in yellow and orange. Per Clay's guides the difference between standard A5141 flipper coils and yellow dot A5141 is about .9 ohms. He shows the A4893 as 2.1 ohms. I would assume the yellow dot bumper coils have about the same drop in resistance. I guess I'll see what the original A4893 coils I took turns off are currented ohming out at and maybe try taking a few more turns off. A flipper coil down around 1 ohm like the yellow dots is getting in dead short range, so I'll have to see if I can get the original coils somewhere between the yellow dot bumper coil range and the original bumper coil range.

I have to believe that is it. Don't know what else could be causing the issue.

Thanks for the ideas guys.

I thought about that but it's more than I want to do at this point.

I did pull out the old A4893 that were in the game originally. I had already taken turns off them before, and they were at 2.7 ohms, which means they were above 3 before I removed turns before, and if Clay is correct, way out of spec for the bumpers. I took more turns off and got them down to 2.1. I'll reinstall and see if I like the performance and also if they P relay issue goes away.

Well, I have to report that it does.

I pulled out the old coils that were originally in the game. I remember that the bumper performance on the game was just as weak as it could be. I think when I put the meter on them, they were at about 3.3 ohms or so. According to Clay's guide the A4893 should be at 2.1 ohms.

I took some turns off and got them down to about 2.7 and high tapped it. Still wasn't happy. That's when I put the yellow dots in and put it back on normal tap and the P relay started dropping out when that change was made. And adding to the suspicion that they were causing it is the fact that no other action on the playfield caused it. Not drops, not rollovers, not slings, nothing. The target would stay lit but as soon as the bumper hit happened, it dropped.

So I got the old coils back out again, took more turns off, and got them down to the spec 2.1 ohms. Today I took the playfield out of the game and reinstalled them. While I was at it, I disassembled the B relay and cleaned all the switches on it. They were really pretty good, I think I did it when I did the playfield swap, but while access was easy I did it. I also cleaned the spoon switches and made sure the EOS on the spoon switch was opening real late so I got a good strong pop.

Put the playfield back in and it works perfectly. P no longer dropping out and finally, the bumpers are performing where I want them. Good strong hit, nothing like a DC rectified would be, but appropriate for this game. I have rectifiers lying around and I could have done the switch, but the bumpers are pretty close to the drops and I don't want to risk breaking them. There's a lot of targets in there. I've broken three drops on Joker Poker recently and I really don't want to get into replacing more of them on Atlantis. They are original to the game AFAIK. I touched them up when I got the game and they still look good.

I don't know what the yellow dots are rated at, my meter died right after I finished taking the turns off.

If you want these yellow dots to put on yours you are welcome to them, PM me your address and I'll send them out to you.

I'm not as sharp on the electronic stuff like Mark G and some other guys here, but I just think a combination of two very low resistance bumper coils, the relay coil all firing, and the fact that the P coil on this game is weaker than what that coil is supposed to be was pulling enough voltage that the P relay coil just gave up the ghost.