Jurassic Park-weak pop bumpers

KingOfTron

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So it seems that the pop bumpers on my JP can pop pretty good, but it takes a pretty hard hit on the bumpers to really get the ball bouncing around. A soft or medium hit with the ball generally doesn't generate a pop, and the ball will often just roll out without much action. It's extremely difficult to save Timmy. All 3 pop bumpers seem to be equally strong with a hard hit and equally unresponsive with a soft hit. Are these the solenoids that need to be replaced? What are some of the causes for weak pop bumpers?
 
I just went through this with my high speed thinking what your thinking, "its gotta be the coils", What I did was adjusted the spoons to be more sensitive to the skirt , not the actual contact switch but the spoon itself and that got the weak pop bumpers firing like I just did a complete rebuild. i also cleaned the contacts and spoons of couse but make sure the spoons are sensitive and the skirts stick that goes in the spoon is centered and you shpould be good to go. Try that i8 bet that the problem, all pop bumpers all makes and models work generally the same. I got this info off pinrepair.com i believe it is. Good luck. let me know it it work for you? The leaf adjusting tool works excellent for this!
 
also I read where some folks unwind a few layers of wire off the coil to get more power off the coil which gives it more "pop' i choose not to do this. What part of ARIZONA you at? I'am 40 miles east of Phoenix
 
Thanks for the tips guys, I'll check it out this afternoon and see what I can do with them. I live in the northwest Phoenix/Glendale/Arrowhead area.
 
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Steelhorse summed it up pretty good. You need to check that the spoons aren't worn, sometimes they get a hole in the middle that will hang up the finger from the skirt. Also adjust the leaf switches so they trigger correctly and clean the contacts. After doing this, they'll trigger just fine. If they are weak after doing this, you need to investigate the coil sleeves, plungers, and stops.
 
I popped open the machine when I got home this afternoon and snapped a couple of pictures of the pop bumper underbelly. The switch contacts are pretty stiff and wouldn't really bend, the only thing I could really do was just try to squeeze them closer together. Is there a way to get them closer? How did you adjust the spoons? Here are a couple pics:

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It seems to have helped, but the ball still doesn't stay in there as long as it does in my other machines. Here's a video I just took after trying to bend the metal switches. Is this the normal amount of time the ball should be bouncing around in there?

 
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On launch, my ball times in the pop bumpers vary widely but they are usually kind of short. Longer times are when it is shot into the bumpers and there is more of an initial upward trajectory. However, I think your times overall do seem a little short compared to what I see.

Bend the upper blade of the switch down some so that it isn't pressing up on the spoon so hard. It looks like it is forcing pretty hard on the underside of the spoon. You don't adjust anything on the spoon itself, just the contact force of the upper blade. You can probably also tighten the gap a little between the blades, but that issue may take care of itself if you bend down the upper blade a little bit. From what I can see, the gap looks a little wide. Just play around with it until you get it right. Anything you do can be undone with a little more bending, so adjust away.
 
the contact on that particular switch looks too far apart to me. it looks like the blade has been bent at some point - you can see the "knee" in the blade if you look at it. as stangbat says, you should bend it back to get the contacts closer together. there is a tool to do this, but i just use a set of small needle-nosed pliers. put them on the blade close to the base and bend until happy.

i've attached a video i just made of my pop bumpers in action. this is typical of my games now - of the three ball launches, one long one, one medium one, one short one.

note that this will also depend on the slope of your playfield. if it's too high, your ball won't stay in the pop bumper field for as long. mine is set at 6.5 deg.

 
and a pic of the switch on mine - the contacts are closer than yours i think?
 

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Took some needle nose pliers to the blades this afternoon and it worked awesomely. The ball really bounces around in there now which totally gives the machine a little more life while playing. Thanks for your help guys!
 
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