Sweep at 66 problems

[Kat]

Okay, got one for you guys.

I've got a machine that will intermittently (5 out of 15 frames) chatter past 66 degrees. Meaning, sweep drops, contactor will chatter twice and cause the sweep to drift in. Then if a head pin is left, the sweep will "clip" the head pin while in the scissors, causing it to fall when respotted.
Things I have done/changed:

MP Chassis is not a fault, swapped with known working from neighbor machine.
-Changed SA & SB microswitches
-Changed stators
-Re-wired C1 cable harness
-Changed SWR & SWSR switches on BE box.
-Took readings on Caps in wireway, good.
-Re-timed all cam microswitch levers to spec.

Any other ideas?

[Rep]

Re: Sweep at 66 problems

I'm probably not the guy to post as being rather ill I haven't even seen the back in 3+ weeks [img]/content/btubb/images/%%GRAEMLIN_URL%%/frown.gif[/img] But I was thinking maybe something up front at the control desk if your old toggle switches are still hooked up? I know they cause goofy stuff sometimes. Just a thought

[8270king]

Re: Sweep at 66 problems

Sweep reverse switch......it is wired into all sweep functions.

Change sweep capacitors anyway.

Offspot switch?

JK

[Dutch]

Re: Sweep at 66 problems

I agree with King. Change the capacitors anyway. It wouldn't be the 1st time an electrical component tested OK but wasn't.
Also check spring tension on SB follower. Probably OK but the way you describe it, it sounds like SB is somehow bouncing or getting activated briefly.

[Kat]

Re: Sweep at 66 problems

Jerry & Dutch:

I just changed all 4 caps to see. The SWSR has also been changed.

Next thing would be to change out the resitors that wire into the caps.

I'm gonna go bowl on it and I'll let you know what I find. [img]/content/btubb/images/%%GRAEMLIN_URL%%/mad.gif[/img]

[Rep]

Re: Sweep at 66 problems

Definately weird to day the least, good luck finding it Kat

[Lampie]

Re: Sweep at 66 problems

You changed the stator so I think you have westinghouse motors, do you still use centrifugal mechanisms/switches ? If so the mechanism can be the problem if it stays down too long(weak springs?). This is just a wild guess, good luck.
Martin

PS How's the condition of the sweepmotorshaft??
With alot of wear you most likely get problems at 270(+/-)but maybe....

[TheGMan143]

Re: Sweep at 66 problems

Check the wire harness to the front-end S and T switches... a frayed or broken wire in the harness will cause some very strange problems. While you're out there, check the switches for signs of grease or oil leaking on to them... if any gets into the case and on to the contacts, they are only handling 'signal' voltage, which doesn't have the amperage to burn off contaminants and keep the contact pads clean. If you're really ambitious, change the switches out (the ones you didn't already) with new ones and completely eliminate the question of whether or not they're causing the problem. Table switches can cause sweep problems as well.

Also, check the incoming AM&C wires... make sure that there are no frays or pinches that could momentarily activate the instructomat circuit.

[Kat]

Re: Sweep at 66 problems

UPDATE:

First off, thanks to all for their suggestions.

Okay, I THINK (read, THINK) I have it fixed. After changing everything under the sun, I changed the S Gearbox with yet another from a different machine. So far it looks good. I guess the one I pulled originally from the neighbor (which had NO problems) also has an issue. Possible slop in the worm wheel. File that in your minds guys when you have something like this for future reference.

Thanks again for the ideas guys.

[AmfPro]

Re: Sweep at 66 problems

Sorry to catch this thread late Kat--The 2 things i would have checked first having had this happen a few times were-1-change the S gearbox--possibly something worn inside or a completely wornout output shaft splines- or - 2. Check for loose sweep crank arm and possibly worn half moon key that sits inside sweep crank arm.
Since you already have done so much-these are the 2 i would try also.
I had a screwy problem like this a few times and it was a loose crank arm most of the time-letting the sweep move in from 66 a little too far and sometimes hitting head pin on a respot and others going in further and starting with the table and ending up in an interlock. Moonlight bowlers constantly hitting the sawep accelerates the loose crank arm problem. Pro

[John_Galt]

Re: Sweep at 66 problems

Originally posted by AmfPro:
change the S gearbox--possibly something worn inside or a completely wornout output shaft splines- or - 2. Check for loose sweep crank arm and possibly worn half moon key that sits inside sweep crank arm.

<font size="2" face="Verdana, Helvetica, sans-serif">Bingo!
I'll place my wager on 785 501 179 teeth being worn.

I'll also put some money on output shaft splines, but not near as much.

If it increases in frequency over time, it's definitely the gear teeth. They're nubs now, they'll be stubs by the time it creates more than just a nuisance call.

C