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Noisy motors - Lubrication issues/questions

S

SFM-Ptgal

I have 2 Harris triple deckers, one bad, the other not so good. Both have a common issue: terribely noisy motors. Since "no lubrication needed" is stated on the manual how can I solve with this problem? From 2 machines I'm trying to make one reasonable working one.

Another question: My Harris turntable is under "maintenance". I've removed the platter felt pads but a layer of a very sticky adhesive tape wich supported the felt glue remains sticked to the platter. Is there a not so hard way to remove it? I going to sand the platter to recover it's brightness. I also need to know what lubricant grade can I use on the platter shaft? Can I go to the carshop carrying the turntable and ask "can you drop some oil in the center hole, please?"
;D

TKS!
 
I use Acetone to remove glue. As long as there is not any plastic around it works fine. MEK works even better but that stuff can be dangerous. Don't sand the platter.

I would suggest using Sewing Machine oil or just a graphite lubricant. I would not recommend motor oil.
 
I've also found WD-40 and Ronsonol (cig lighter fuel) to be good for removing sticky residue.

I don't know if this would apply in your situation, but I've frequently oiled cassette player capstan bearings with something like lightweight 3-in-1 oil -- there are some that come packed in little tubes with a needle to apply. Ditto with the motors. That keeps them going for a good long time.

Or maybe the liquid graphite lubricants like Lock-Ease could work in this situation? Use a syringe with a hypodermic needle to squirt a few drops.... worth a a shot.
 
I've had noisy motors in the single play Harris cart machines (not the triple-deckers). But I suspect the problem is similar. Oil won't cure the problem for very long.

You need new bearings for the motors. I vaguely remember seeing a Harris 3 spot, believe that it just had two bearings, one at the top of the motor, one at the bottom. (The ITC triple decker had a third bearing at the top of the shaft.)

Not fun to take the motor apart --and you will need a bearing puller. If you live in any size city you should be able to find a supplier for the bearings, & they probably can sell you a bearing puller, too. I live in an industrial city of with around 75,000 people in the metro area, these small bearings are used in many industrial motors. It's been a while, but I had no problem finding replacement bearings locally, nor were they particularly expensive. Also note, there are two grades for a given size bearing--you probably should spring for the higher grade, the low grade ones are used in such things as roller blade skates.
 
TomT said:
I've had noisy motors in the single play Harris cart machines (not the triple-deckers). But I suspect the problem is similar. Oil won't cure the problem for very long.

You need new bearings for the motors. I vaguely remember seeing a Harris 3 spot, believe that it just had two bearings, one at the top of the motor, one at the bottom. (The ITC triple decker had a third bearing at the top of the shaft.)

Not fun to take the motor apart --and you will need a . If you live in any size city you should be able to find a supplier for the bearings, & they probably can sell you a bearing puller, too. I live in an industrial city of with around 75,000 people in the metro area, these small bearings are used in many industrial motors. It's been a while, but I had no problem finding replacement bearings locally, nor were they particularly expensive. Also note, there are two grades for a given size bearing--you probably should spring for the higher grade, the low grade ones are used in such things as roller blade skates.
Click to expand...

Am I wrong or the Harris cart machines wich I thought to be among the best are quite crappy?
 
littlejohn said:
In my opinion, you aren't wrong.
Which is why ITC soldiered on with cart machines and Harris left the market.
Click to expand...

I'm disapointed... Harris is a reference for me. Having 2 noisy triple deckers and recorder makes me change my opinion... At least the turntable is great and the Gatesway 80 wasn't connected yet.
 
littlejohn said:
In my opinion, you aren't wrong.
Which is why ITC soldiered on with cart machines and Harris left the market.
Click to expand...

Yeah, I swear by the ITCs. They're tanks.

The BE brand machines also weren't any slouch. My first radio job (in college) had those for on-air. Never had a problem with them, they ran 24/7.

I've been told to stay away from the old Fidelipac machines....anyone have any idea about how good the new Dynamax machines being put out by the Cart Guys are? Seems like they're the only manufacturer left making these beasts (and the tapes for them). They bought the Fidelipac name and product line.
 
I used a tiny drill bit and made a hole in the plastic cover on top of the bearing and an insulin needle to inject it with a teflon based oil. I think I used the Slick-50 treatment that was added to moter oil. It worked great for me. (Disclaimer: Your results may vary) Good Luck
 
Actually, the Harris Criterion 90's were not that bad (white case/black trim); we used them for years. They were repairable, for one thing. Apart from the motors, the filter cap would go bad, and they would miss cue, or do other strange things. But it was an easy fix, just pop another cap in. There were far worse cart machines on the market.

Motors have always been the weak point on a cart machine--but then again, time between failure would be measured in years, sometimes decades. How many ten year old computers do you have around?
 
Yesterday I took one of the Harris Criterion triple deckers and decided to check the motor. It was noisy, very noisy. Since I don't have much to loose I removed and opened it. I've blowed it and lots of dust was spread. I didn't managed to reach the bearings. I dropped a very few drops of oil (sewing machine... I know) and left the capilarity do the rest.
I ran the motor continuosly for about 30 minutes and seems that the noisy is gone.

There's a remaining issue: Prim. Cue tone pass undetected on deck 2. It defies any logic. Swaped decks, cards and... nothing :'(

Something to keep digging on...
 
A station that I worked at had several Harris 90 cart machines.

We didn't have any of the triple decks but I would ass/u/me that they are similar.

We always got longer life out of the bearings with lubercation - usually a 3 in 1 oil. A little dab will do it.

As for the cue problem - if its not on the board I would suspect the head. SOmetimes they wear excessivly on the cue portion of it if the allignment was done for "audio" only.

I have also seen a bad wire from the head to the cue amp. If the machine sat on a shelf for a while it may be an oxidation where the connector is on the back of the head.
 
As long as we're talking noisy cart machines, I have to share this story. There was a part timer who encountered this problem. He found a can of WD-40 and sprayed it in the cart machine, tape heads and all. No, the engineer didn't shoot him but would've like to have the chance. Of course, this same genius on another occasion kept doing his shift knowing the transmitter had shut down.
 
SFM-Ptgal said:
Yesterday I took one of the Harris Criterion triple deckers and decided to check the motor. It was noisy, very noisy. Since I don't have much to loose I removed and opened it. I've blowed it and lots of dust was spread. I didn't managed to reach the bearings. I dropped a very few drops of oil (sewing machine... I know) and left the capilarity do the rest.
I ran the motor continuosly for about 30 minutes and seems that the noisy is gone.

There's a remaining issue: Prim. Cue tone pass undetected on deck 2. It defies any logic. Swaped decks, cards and... nothing :'(

Something to keep digging on...
Click to expand...

That's not going to last long at all. But the good news is that you can change those bearings pretty easily. I've never done it on a Harris, but many times on an ITC. I never even had a bearing puller. Find something flat and blunt to rest against the inner ring, the one around the shaft, and lightly tap the shaft with a hammer. It should slide right out.

If you don't have a bearings shop, you may be able to match them at an auto parts store. It's been a long time, but the last time I did it I was back in business for $20.

The exception to that in an ITC was the "top bearing" of their old triple deck. (The RP series, not the Delta.) That bearing was allegedly "self aligning", to make up for the fact that the box was never quite square. Prior to the self aligning bearing, ITC tech support used to have you loosen all the screws on the unit and take a carpenters square and try to square it all up before tightening the screws again! Doing so often made your noise go away.

But that bearing wasn't in the motor at all. It was at the very top of the long, triple deck motor shaft, as a support at the top of the machine.

As for your cue tone problems, this is tough without a schematic. If there are 3 relays, one for each board, you might try swapping those. Otherwise there must be a solenoid control board somewhere which has the problem.
 
SFM--do you have a schematic? I have a Criterion 90 book around somewhere--the cue boards should be the same for the three spot as for the single play.

My bet would go to head leads. Broken lead--no audio to card--won't see cue tone.
 
TomT said:
SFM--do you have a schematic? I have a Criterion 90 book around somewhere--the cue boards should be the same for the three spot as for the single play.

My bet would go to head leads. Broken lead--no audio to card--won't see cue tone.
Click to expand...

;D It's fixed. I swaped a head from the other triple decker and now the PRIM tone is detected... and... It plays fine!!!! :D I've picked the audio output directly to the headphones and it sound good. The heads show no ware, and no noticeble wow and flutter, perhaps just a phase adjustment needed. For a 28 year old cart machine used intensively 23 it's very good ;)

Thanks guys!!!
 
Well, another topic from ancient ages brought to life...

Two days ago I replaced the Criterion 90 motor bearings. I managed to open the motor and removed them without a proper tool... A small flat screw driver and a small hammer. Tapped them and they poped out. The old bearings were running freely but I felt the "grains" on the running course. The new bearings are SKF 608z.
The machine is now running even more quitely than b4

pedro
 
SFM-Ptgal said:
Well, another topic from ancient ages brought to life...

Two days ago I replaced the Criterion 90 motor bearings. I managed to open the motor and removed them without a proper tool... A small flat screw driver and a small hammer. Tapped them and they poped out. The old bearings were running freely but I felt the "grains" on the running course. The new bearings are SKF 608z.
The machine is now running even more quitely than b4

pedro
Click to expand...


Congratulations Pedro! that's awesome.
 
We all "hate" cart machines, compared to computer playback for spots---

But a cart machine never gave you the "blue screen of death"!!!

Fun to have something you can actually fix with simple tools and some determination.
 
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