Accel motor belt loss

[Oldsmagnet]

Need your professional thoughts and ideas here once again, folksl... Got a lane that suddenly decided to start flinging the accel drive belt yesterday, and I haven't been able to cure it. The adjustment procedures, of course, are cryptic, and I believe they're followed as closely as possible. I've replaced both drive and accel. belts with new, and still no fix.

When a ball goes through, the accel belt (the wide one) deflects towards and into the drive belt (the short one) sometimes only bumping it, but more often than not, flinging it completely off.

I presume it's somewhat normal for the belt to deflect that direction when a ball goes through, but I'm guessing not ~that~ much... obviously The belt, at idle, rides 1" away from the even # machine's side of the pulleys. Front and back. And tracks evenly, perhaps 1/8" of side-to-side wobble. But when a ball goes through, about 30% of the time, it'll fling the drive belt off.

Any thoughts? I'm guessing ~someone~ here has had this problem at some point, since we've got the best minds in the world here, I swear. This has been a year of "first times" for me, regarding the oddball @$%^ I've had to fix, but it seems every time someone here has seen it before. So I'm hoping someone here has seen this before... and cured it!

Thanks, as always...

[Roscoe]

Re: Accel motor belt loss

Olds:
Your correct in guessing that others have had this same problem. It includes everyone that has A-2 returns. Manuf. has tried many fixes, different belts, different pulleys, with different radius etc. Most common cause, worn pulleys( ie. convex worn to flat.) best cure, short of replacing very expensive pulleys, Zot kit no.11188-0. Raises belt over track, releving the tendency of the belt to ride off the side of the ball. Installed lots of them, little loss of return time, PIA to install, owing to lack of work room, but well worth the time. Pretty much puts that problem area to bed
Roscoe

[masternut]

Re: Accel motor belt loss

I agree the Zot kit will pretty much eliminate any belt problems,we have modified all 116 lanes(58 acelerators)in our 3 A-2 centers.We haven't had a belt track off since we did modification 9 years ago.

To make it a little easier to install kit, place a bowling ball at rear of accelerator to hold up accelerator when removing the rear brackets,also super glue the washers(shims)to the brackets to hold them inplace while you start bolts
Good Luck
Peanut

Re: Accel motor belt loss

HELLO ID REPLACE THE LARGE FRONT PULLEY IVE HAD THAT HAPPEN WHEN I REPLACED THE PULLEY THE PROBLEM WENT AWAY GOOD LUCK J B

[Charles Heuer]

Re: Accel motor belt loss

Olds, Forget the ZOT kit, replace the pulleys. Been there, done that. Pulley replacement will cure your problem. Tension on the long belt is very important so make sure it is set right. Its always best to change the pulleys in pairs if your budget allows.

[This message has been edited by Charles Heuer (edited 01-12-2000).]

[Drillmn300]

Re: Accel motor belt loss

The Zot kit is where it is at, after converting I can go back and use some of the belts and pulleys that failed the first time around due to use. I have not adjusted the belts or replaced a pulley since.
Drill

[Oldsmagnet]

Re: Accel motor belt loss

Well, gotta send a big thanks to all that jumped in here, saved my bacon again. And so far, not a penny spent... few bumps and scrapes, but not a penny spent! I looked at the Zot catalog closely, and how they showed the long belt curling off to the side of the ball. That diagram sparked the brain to start functioning again, so I ran a ball halfway through by hand (yeah, power off) and watched where the belt rode on the ball. Then I adjusted the pulleys to center ~that~ and ran a few balls through flawlessly. Then I shot three games there in a row, flawless. So tonight, I get there, the league has thrown like 4 balls... belt's off. Go figure, expecting another rough nite suddenly, emphasized by the ~other~ machine that I ~thought~ I had cured (and rolled 4 consecutive games on it, and open bowlers with like 6+ lines... flawlessly...) ~It's~ blacked out when I walk in, also...

Sooo... I tweaked the back pulley mount a bit more, moving the belt farther away from the drive belt, and never had another problem.... then I look at lane 12, just a thrown belt, a totally unrelated problem from the gremlins I'd fought earlier in the week... But they never used that lane anyways.

My question regarding the Zot, for those who use it. It ~looks~ as if the whole premise of the kit is to reduce tension on the belt. Could that not also be achieved by simply backing off tension on the long belt? Looking at that lane, it seems side-to-side alignment is much more critical than belt tension, and aligning the belt with a ball on the rails seems more logical than the book's method of lining it up with the pulleys instead. Just food for thought. I'm not gonna lose any (more) sleep over that, since it's cured, IMHO, and it's not a problem we have seen much of here.

And does anyone offer a better shield for the drive belt pulley? Seems like lots of stress could be diverted, if there were some sort of guard ~forcing~ the belt to stay on the pulley... Seems somewhat anal to run a belt on an all-flat pulley. Period. And I ~really~ don't get these crowned pulleys... seems like those would have even higher tendancy to drop a belt here and there.

Just food for thought, I guess, since, as noted, I'm not gonna lose any more sleep on it

Thanks again, all!

[GRAMBO]

Re: Accel motor belt loss

Hey Oldsmagnet
We slowed all our accellerators down by putting on a real small pulley on the motor.
It helped greatly on keeping the long belt tracked.
The high crown on the new pulleys helps keep the belt tracked.
The machines I work on now at USPS have hundreds of flat belts running at high speed.
Although the belts are only about 2 inches wide ALL the pulleys are crowned for tracking purposes.
We use to save are old bad accelerator pulleys and have a machine shop cut them down and put in a crown.
Was cheaper than buying new ones.
Hope this helps.
Grambo

[KL Kevin]

Re: Accel motor belt loss

Olds:

FYI ...

The reason for the crown on the pulley is that any flat belt will track to its tight side.

A flat belt put on two pulleys that are flat, don't have guide flanges to hold the belt on, and aren't precisely parallel to each other (creating a tight side), will be thrown off to the tight side in a matter of seconds.

By crowning the pulley, when the belt deflects to either side, the CENTER of the pulley becomes the tight side (the deflected side gets loose, actually) , and the belt automatically brings itself back to the center. Any time the belt goes off center the least bit, it will right itself, provided the pulleys are reasonably parallel to each other to start with.

Hope this is of some use:

Kevin

[BT-Jerrid]

Re: Accel motor belt loss

Hey Olds,
This as an all to familiar experience for many mechanics with accelerators. A good starting point would be to raise your accelerators, I did this and cut my drive belt flinging by about 95%. I took the cheap way out and built my own brackets out of some welding stock I got from the hardware store (you can do the whole house for about twenty bucks) I made the front brackets 15 and 1/2" and the rear brackets 15 and 1/4" long, use the old brackets for hole placement. The idea is to get the ball to touch as little of the belt as possible. Dont make the rear brackets any more than 15 and 1/4 or youll have problems getting balls into it. Another course of action would be to use the high crown pulleys (expensive but well worth it). You might also consider slowing them down with a smaller drive pulley. Once you think you have it tweaked to perfection, a good test is to go into the proshop grab a 16 lbs. plastic rhino, take it to the shop, soak a rag in lane oil and wipe the ball down. Send it through the accel. If the belt stays on, your work there is done hope this helps.

Jerrid

Re: Accel motor belt loss

I think KL Kevin is on the right Track here ....

I just started working with accel.'s again (and I don't remember them being such as pain in my aryes, of course they were new back when)....

All I got to say is, one pulley must have a good crown or your dead meat....

[jim]

Re: Accel motor belt loss

Hay guys....anyone have A2s with AMF drop sweeps (the wooden Tracks) well i hadda slow em way down to keep balls from jumping off the tracks and rolling down the gutters and knocking down Bowlers..LOL anyway hadda install 1/4 h.p. motors 1725 or 1750 rpms only thing that would work and i converted the old style flat pulleys to v pulleys works great no more problems with any belts coming off at all.This also can be done wherever the retarders have been taken out.1/4 hp motors will get the ball back and youll have lesser ball damage do to slamming balls into the Lift Hoods..

------------------

[Oldsmagnet]

Re: Accel motor belt loss

Little update here... The pair in question ran flawlessly until Monday, when ~one~ particular ball would ~break~ the short belt ~every! time it went through. The last time it went through, the long belt came off, too, and the whole assemly just sorta self destructed... loudly. Moved the bowlers, pieced it back together, and ran it that night, flawlessly. With used/abused belts... (Short belt's cracked halfway through.....) Next day, flawless, next day, flawless... That ~night~, whilst attempting to bowl league 8 lanes away, it'd break ot fling every 10 minutes or so. Stay till 4AM rebuilding the @#%@^ thing... Bowled 4 games, flawlessly. ~No~ deflection. Period. (I found the shaft for the front pulley was ~shot~, so I replaced the shaft and pulley) No deflection anywhere. So I went home...... It made it through ~3~ balls this morning... 3. (Yeah, I was thrilled to hear that!) Pinchaser puts some nasty belt dressing crap on the belt, no it sounds awful and the belt's all gooey... and ~still~ flung it off all night long. (Oh, and gremlins all over the house, all night long, also.... Can you guess, we're hosting a big tournament Sunday?!?!?) Anyway, too late to order parts now, we need a 12 lane house again for this tourny... Sooooo, here's a pinsetter modification for all y'all to take note of....

Took an idler pulley from the shelf, (Didn't even take note to what it was ~meant~ to fit... but it's flat, not V, with lips on either side...) Drilled a hole right in the side of the accel. motor's drive belt shroud, and mounted that puppy right in. Only had a cordless drill, so I just poked a hole in it, and called it good, but I might go back and slot it out, if it becomes a problem. As it is, it just barely clears the belt. Any deflection, theoretically, should contact the pulley, and keep it on track that way. If it can get around it, I'll use the idler to put tension on the belt and ~force~ it into submission! I believe the root cause of the problems is the motor's pulley has been worn at a slight angle... But no spares, and no time to cure or replace.... band-aid time!

Just wanted to share that with ya, incase any of you get to pulling your hair out over a similar situation.