This is most likely a more convoluted problem. On the bottom of the playfield there's a number of relays that change the scoring. For example, the spinner or pop bumpers can be worth 1000 or 10,000 point (for example, actually i don't really remember exactly on this game, but for this example, we'll go with that.) There's a change relay that controls this, usually with make/break switch(es). If the switch(es) are mis-adjusted, you'll get both 1000 and 10k scoring for that particular device. So bottom line... your problem may not be on the 1000 or 10k relays, but elsewhere.

Wouldn’t it probably just be that the switch on the 10k reel that tells the 100k reel to fire is not gapped properly and is making contact each time the 10k reel fires?

But yeah since it’s all players that would be pretty strange that they all needed adjusted.

Clay's logic is sound for many games, however I don't think there are any targets on GP that toggle between 1000 and 10,000 pts.

I suggest checking 2 other possibilities:

1) There is a 10-prong Jones plug that plugs into the lower left corner of the head (FYI: In the manual, Williams calls the component board in the head the "insert"). In that plug, there are 2 adjacent prongs/sockets that go to the 10,000 and 1000-pt relays. Inspect both the male and female ends of that plug to make sure there is no metallic debris or exposed wire that might be shorting those 2 prongs together. A short at this Jones plug could result in your issue.

2) A consultation with the schematic (area E-20/21) indicates that the #1 star relay indeed has a make/break (M/B) switch where one pole goes to the 1000-pt relay and the other to the 10,000-pt relay. This could also cause your issue and is similar to what Clay was describing as a misadjusted M/B switch where the center blade is actually touching both outer contacts.

Please check these 2 possibilities and report back. If it isn't one of those, it may be a more convoluted problem.

Lee

More info:

In the 10-plug Jones plug that goes into the backbox, the wire colors to the 10,000-pt and 1000-pt relays are red/orange and brown/yellow, respectively. The plugs are located at the end where the wiring bundle is. Inspect those closely for a short.

The exact same colors are utilized for the two switched poles of M/B switch in the #1 star relay. Brown/yellow goes to the 1000-pt relay and red/orange to the 10,000-pt relay. A grey/yellow wire comes into the switched middle blade on that M/B. That should help locate the proper switch.

Good advice from Runbikeskilee :

If that doesn't help, start by finding out which circuit if any on the 1000 Point relay is causing the problem:
Manually push the 1000 Point relay. If the 10,000 Point relay pulses, jumper the switches on the 1000 Point relay one at a time until you find the switch that pulses the 10,000 Point relay.

Pinball (resized).png

You mean spinners?

I've made some changes to mine to make it harder. I rewired the A-B-C-D targets in series so that you have to get all 4 down to advance the star bonus for double bonus and knock them all down again on the same ball to light EB. I also removed two wires from the spinner relay so it only advances the bonus 1 spot for every 10 spinner revolutions. I just felt it needs to be a bit tougher.

It is definitely a great game regardless!

I may have to try these mods, I rolled my over a few times now, need something a little more challenging.

https://pinside.com/pinball/forum/topic/has-anyone-changed-rules-on-their-em#post-3973565

Page 9 of the manual shows post adjustments to make the game harder
http://mirror2.ipdb.org/files/1072/Williams_1976_Grand_Prix_Manual.pdf

Thanks!

Tell us what's firing continuously. Also, see if unsoldering the wire you soldered makes whatever-it-is stop firing continuously.

On williams score reels, as part of any repair, you should tug on each and every wire on the score reel switches. Williams often didn't use enough heat to solder the wires, and often they delaminate their solder off the switch solder lug. If one came off, i'm betting you'll find more.

What happens when the ball lands into the bonus collect saucers on the right or left?

Check at 13.5 on the schematic for Top Eject relay. There is a make/break on the score motor that could be the cause.

Agree- that sounds like a score motor switch is not closing/opening correctly and that the hold relay on the bonus saucer is not being reset. Also at least possible the hold switch on the relay is gapped closed... check for switches that dont change state on the relay and on the correct stack on the score motor

If the Top Eject relay is activating, check these switches and this circuit.

Pinball (resized).png

I am slightly confused- so before proving a dumb answer... when you say stand up switches do you mean the switches behind the rubber on the left and right side just below the bonus award saucers/hole?

It scores 500 and advances bonus continuously every time? Or does it stop sometimes and if it does what makes it stop?

You may have some "floating" contacts. Crimp the contacts on the relays involved with a pair of needle nose pliers.

And if not, check the whole sequence leading up to the two bonus relays at 15 on the schematic.

Those switches behind the rebound rubber are two sets of switches for adding the bonus (front set) and adding the score (back set). If the front set of switches is gapped too tightly and touching it will keep adding bonus continuously. If the back set is gapped too closely and touching it will keep ringing the chime and adding points continuously. Take the plastic off from above and see how close those contacts are. Should be about 1/16" with the rubber ring in place and pressed up against the first leaf blade. Increase the gap as necessary.

All I can say is the key to switches is to watch carefully as you move the score motor. A close should slightly move the stationary switch when it hits- and an open should fully open with clear air. The gap is kinda a function of travel. Most score motor switches actually take a good hit and move a bit but its fast when you move it- so ya gotta look really carefully.

It could be somewhere else but its usually not. If you fixed 80 % of a constant problem adjusting one thing- its 99.5% its beacuse you adjusted it 80% correctly. EMs are just not that complicated.

Of course if this is a jacked up machine your rescuing anything is possible and the next switch could be bad but its only one or two places in the whole game. So your really close to done.

Keep up the good work!!

Just a thought here, did you check the contact on the 500 point relay? this relay is attached to the underside of the playfield. I had a set of contacts a little too close on mine and through vibration it was being made and scoring points.

This is a little bit of a guess because I don't remember for sure, but I think the 500 relay has a hold switch through the score motor?.. that circuit could be the issue. The manual for this game is awesome. Check that relay switch and find the hold switch if it has on (confirm then trace on schematic first). If that switch is Ok it's one of the other switches down from there to the score reel. Not positive but the release is probably coming from the score motor.... please confirm hold with manual then if yes, I think you are there and will find the issue. If no... I will have to look on schematic and can do so. Let us know.

Use the manual on this game, it's really really good. Maybe it's just me, but I "Just Get" this manual... some other EM manuals I find to be far less inviting.

If your not sure what a hold is, I think There is a sticky thread in the EM hang out that Steve wrote which has animations for many common EM circuits. I think he goes over a hold function in there... it basically lets the machine count To 5 to pulse the 100 point reel 5 times through the score motor rotation and other things like that.

Hmmm... at this point it still seems like a stuck switch on the playfield- but there are only two possibilities which you appear to have checked. I would start by throwing paper between all the contacts on the play field switches behind the rubber ring on the left and then the right side of the game and see if you can isolate the issue to one or the other side switch- also check for solder drops and other issues with switch stacks to ensure no shorts!

If both sides cause the same problem then isolate all contacts on the 500 point relay and remove paper from playfield switches and confirm problem goes away (but no scoring). If you take 500 point relay it should stop this for sure- and depending on what happens with isolation of the playfield switches you may have a better idea of whats going on.

I like looked at schematic briefly and this is probably as good a place to dig in as any- it really seems like a shorted or closed switch but this should help confirm.