ball lift belt popping off

[knuckles]

Anybody got any ideas about keeping the upper pulley on the ball lift from twisting back and forth causing the belt to pop off? I have the lift centered, the uprails are in good shape, I have replaced the bracket-pin-roll bearing that connects the upper pulley to the ball lift shaft. I have played with the tension on the big spring (tighting and loosing). I think the book says the spring should be 4.5 inches long but I checked other ball lifts and there all different. What I did was drill and tap two holes in the yoke and put in set screws. I've done this before and it is still working. I was just wondering if I am missing something!! It seems like two much work to drill and tape holes if I don't have too. Knuckles--- Larry

[vinson]

Re: ball lift belt popping off

If every thing else is true, check and see what yoke assembly you have. The bracket that keeps it lined up with with the body could be connected to an older yoke. The way to tell is does it bolt up top with one hole or two, you would see the older one hole yoke is shorter allowing a little more play and turn.

[toon30s]

Re: ball lift belt popping off

Make sure that the part of the belt that rides in the groove is not seperating. I know it sounds too obvious, but I've seen it. Let us know what you find!!
Toon

[8270king]

Re: ball lift belt popping off

1. Check to see you have the proper belt. I believe there is a gauge in the vantage book. There are wide and narrow groove pulleys and I hope you have the same top and bottom on your ball lift. Then it is a matter of putting on the right belt.

2. I had the same problem on some PBL's a few years ago. Balls would spin for a while then kick the belt off. If this is happening get some Stahl's lift rail cover and the spinning balls and the belt riding off will go away.

Jerry

[Coors]

Re: ball lift belt popping off

id say you have an alignment problem, dont worry about whether your lift is centered between the rails (many rails are twisted and/or bowed), be sure it is centered over the ball

take the ball cage off the top of the lift and watch the ball/belt as it comes up. you'll see that the belt is being deflected to one side or the other.

ex. if the belt if getting deflected to the even lane side as the ball comes up, move the top of the belt to the even, and/or the track rails to the odd. after a while you'll get a feel for the proper adjustment. when ya get it right you can sit atop the ball lift and the belts "Wave" will run dead center into the top pulley

[Guest]

Re: ball lift belt popping off

Couple of other things to check:

Pull the lift up manually, without a ball. If there is too much tension (as compared to another lift that works fine) your shock could be bad. They usually go bad on the "down" side and the lift will slam down, but ocassionally - they can be bad the other way, and if that's the case, something has to give and it's usually the belt.

Also, look at the lift from the side as a ball goes up. Watch the spline (back) of the belt as the ball is about center up the lift. If the spline touches the center pole here it gets deflected either left or right and the belt will pop. This is caused by a misadjusted upper yoke spring or a stretched belt (it happens over time). Try taking the spring past 4.5 inches (remember - the book spec is for a new machine). I have actually fully compressed this spring to get more life from an otherwise good belt.

Good luck!

[Coors]

Re: ball lift belt popping off

Quote:]Originally posted by pitboss:
Couple of other things to check:

Try taking the spring past 4.5 inches
Good luck![/QUOTE]
my personal flavor is 4 1/4"

and ive seen some go 4". coincidentally that mech/house went through alot of upper yoke bearings. (i took over after him)

[knuckles]

Re: ball lift belt popping off

Hi everybody. Since I posted my problem I have found about 4 other problems. 1st problem I found was the rachet wheel on the PBL was stiff. So I ripped that apart and rebuilt it, works nice and smooth now. 2nd problem was the shock was bad. 3rd problem was some of the bearing sleeve's in the two yoke assemblies were becoming football shaped, making the ball lift jump all over the place. 4th problem is the pulley's are the deep grooved pulley's and I have the wrong belt on there. I missed one thing, when I took the lift apart the top yoke assembly was almost floating on the big black shaft. I guess with all the banging around the lift was doing, the shaft wore out the inside opening of the upper pulley yoke. I put a new one on and it fit nice and snug. [img]/content/btubb/images/%%GRAEMLIN_URL%%/smile.gif[/img] [img]/content/btubb/images/%%GRAEMLIN_URL%%/smile.gif[/img] For the time being I replaced the lift belt with the wrong belt again (that's all I have for now) until I get the right one. The original belt was all torn up on the inside and outside with huge divots. I think I'll be checking all the PBL lifts after this episode. Thanks for all the help guys. I love this place. THANKS MIKE FOR BOWL TECH. [img]/content/btubb/images/%%GRAEMLIN_URL%%/laugh.gif[/img] [img]/content/btubb/images/%%GRAEMLIN_URL%%/laugh.gif[/img] [img]/content/btubb/images/%%GRAEMLIN_URL%%/laugh.gif[/img]

[ October 18, 2001: Message edited by: knuckles ]