Jennings J400 Reels won’t spin??

[Amechanic]

Hi All 
I have a machine here that I’m not familiar to me. It’s a Jennings J400.. I have fix a few issues, but one has me stumped.. The reels don’t spin what the handles pulled. I see the reel stop solenoids working. If I setup the game on a payout, it pays. Not sure where to look, or check. I’ve cleaned all the edge board connectors. I’m not sure if this problem is with the logic board? Any help would be greatly appreciated..

[Op-Bell]

The reel motor is 110V, powered through a solid state relay the size of a pack of cigs. There are two of them under the logic board, the other one is for the hopper.

It's unlikely the relay is trashed, as the usual failure mode would be short - the reel motor turns all the time. More likely the driver on the logic board is dead. You can check with a DC meter across the low voltage side of the relay - it should show a voltage (less than 24V) to turn it on, no voltage when turned off. Make sure you know which side is low voltage or you'll annoy the meter.

Re: your other message, yes, the handle has a 24VDC solenoid release. If it isn't burned out or disconnected, the problem again will be on the logic board.

[Amechanic]

Ok.. Here are a couple pictures of the inside of this Jennings. I don’t see the relay board you mentioned. The only other board I see is the one mounted piggy back on the mother board. I did find out that it’s not mounted tight when I took these pics. I’ll look into that tomorrow.

So if I attach a 110V test plug to the hopper motor where the two leads are attached, the hopper motor should run. I know I need to take the wires off so not to damage anything in the machine. Where do I test the hopper motor voltage on that board?

[Op-Bell]

Well, my first impression is, that is not a Jennings 400. The J400 had metal reels. Does the logic board have gold fingers or connectors? If connectors, it's a Jennings 700.

The piggy back board is mounted where the solid state relays are supposed to be and from my brief inspection, it looks like two DIY "solid state relays" each consisting of an opto isolator (6 pin chip) and a triac. Since I don't have any J700 documentation I don't know what to tell you. A larger scale photo of the piggy board would be helpful - I can't see much detail on that one.

[Op-Bell]

Ok, I made my own enlargement and I can see that unspeakably horrid and amateurish board has a third triac on it, of whose purpose I have no idea. That board must have been designed at the last gasp of TJM when everyone qualified had left, but the janitor's grandson offered to try his hand at making a PCB after he finished his homework.

I would hazard a guess that the AC live into the board is the screw terminal at bottom center. The two screw terminals on the left look like control inputs. Bottom is probably the hopper. The top one appears to control both of the right hand triacs. Maybe one was not man enough for the job and they had to parallel two, or maybe there's some other undocumented 110V thing.

The center lead and tab of all the triacs will go to one side of the AC - my guess is they're all common and that's the AC input. The left hand pin on all the triacs is the gate, and each will go to one of the six pin opto isolators. The right hand pin on all the triacs is where the power comes out to the motors. Having it in front of you to inspect, you may be able to work it out from there. I think the AC leads will not run through the green PCB behind so you may be able to trace them right back to the motors.

[Amechanic]

The two motor leads go from the motor to the back plane or mother board. I machine tag says this is a Jennings J400 model. I've never worked on one so I'm guessing just as much as you are here.. I'm going to pull that piggy back board tomorrow.. Let me know if any pics angles would help. From the pictures I've seen this logic board looks to be for a J400..

[Op-Bell]

I'll have a look at my own in the morning to see where the wires run and what the colors are. It's a pity yours doesn't have the solid state relays, they were much more straightforward.

[Amechanic]

I have a picture of my board from ramegoom web page. It’s the same as this one. I did also see the other version your referring to there too. Two black relays side by side.

[Amechanic]

I made a mistake in my #5 post. Those hopper motor wires are connected to the board that the reels attach too. Took me a few minutes to see my mistake.

[Op-Bell]

Much better picture. Now I see the wire colors are etched on the board.
0 - black, 1- brown, 2 - red, 3 - orange, 4 - yellow, 5- green, 6 - blue, 7 - violet, 8 - gray, 9 - white.

So 91 means white-brown, 94 is white-yellow, 95 is white-green, 98 is white-gray, 97 white-violet, 87 gray-violet, 92 white-red, 93 white-orange. All the numbers match the wire colors except the white looks gray and wire 87 looks black. The chicklet capacitors all attach between the 110V live and one of the 110V outputs. I would have to see the tracks on the back of the board to know which ones. However, I'm pretty sure the white-red is the hopper motor and the white-orange is the reel motor. The two wires 98 white-gray are the 110V in. Since this is a drop-in for the solid state relays, those wires would have been already on the green board and there were two feeds, one for each relay. I suspect 97 and 91 are the original 5V or 24V feeds to the two relays. 94 is probably the reel motor enable (pull to ground). 87 is probably the hopper enable. And now I see what the other triac does. The odd wire 95 doesn't have a counterpart on the relay version or a proper pad here, but it puts a second triac in series with the hopper triac and it's wired into the tilt relay somehow, so it's a fail-safe hopper lockout in the case of a tilt. They must have had trouble with hopper runaway, maybe if the relay shorted, and that's probably why they put this board in, instead of the relays.

I still have trouble believing that any company with a functioning management would allow such a dreadful piece of workmanship to go out to the public.

[Amechanic]

I hear yes on the workmanship. I couldn’t believe all the wiring in this little machine, and most isn’t tied up!! No wonder these machines didn’t catch on and Bally took over.

[Op-Bell]

They were only made at all because when Atlantic City opened in 1977, New Jersey passed a law that no casino could buy more than 50% of its slots from one manufacturer, and at that time there was really only one manufacturer. Since Jennings didn't have a machine in 1977, it was a rush job. Don Hesskamp designed it - I worked with him occasionally at Games of Nevada. Pretty much the entire production of these Jennings machines went to AC, with 15,000 sold in 1980 alone. They are all without exception the lowest paying slots you'll find anywhere outside McCarran Airport, generally paying no better than 80%.

[Amechanic]

Well I pulled and inspected the relay board, no visible damage. I did unhook the reels and hooked up my test plug to the motor. I found that it would not spin the reels. I removed the motor and gearbox assembly. I then removed the screws and split open the gearbox case.. What I found was that the grease inside had turned into something hard as cement in some parts and a super thick stick lump in the rest. It took me 2 hours to clean up that mess inside. But once cleaned and reassembled with a new coating of blue trailer wheel bearing grease it runs great on my test bench. Once time tomorrow will tell how the machine likes this, or if I have bad driver on the logic board.

[Amechanic]

Well this little Jennings J400 has life again.. After cleaning all the nasty hard, stinky grease from the reels gearbox and reassembling with fresh, the reels now spin again. I was afraid that the reels driver on the logic board was bad, but I got lucky with this service repair. Reel strip 1 is a little low on the marks and it also has a squeak when it spins, but I'm hoping the couple drops of oil I applied will soak it and fix that.. I just ordered some replacement mini bulbs to replaced all the ones that are burnt out. It will be interesting to see everything lite up.. Thanks Op-bell for your help..