Collaro 4 speed single player - can't get to speed

[Edward Huggins]

I'm usually here providing help, but here's my first query.
I have a 1957 Collaro (type AC457?) single player. When switched one (arm swung over to right) it takes up to 15-20 minutes for the motor to reach the optimum speed. Once reached, the motor plays fine for the rest of the session. This has to be done every time. My "solution" up to now, is to turn it on 20 minutes before use it! I suspect faulty/leaking motor winding. Any ideas Folks? Edward

[Hartley118]

Well Edward, I may not have the complete cure, but I can empathise. I have a Collaro 4T200 transcription motor of similar vintage with a similar problem. In mine, it's the shaded pole drive motor that runs slow until it's warmed up. My guess would be that your single player may have a similar motor.

I think that it's the original motor bearing oil that's gone sticky in mine. I've re-oiled the bearings with a very light non-sticky clock oil, which has improved, but not totally cured, the problem - it still takes a few minutes to get to speed if it starts from very cold (say <12C). But it now starts OK in a warm room. One of these days, I'll get around to stripping it down and throughly cleaning and re-re-lubing the bearings, but I'm living with it pro tem.
Martin

[Edward Huggins]

Thanks for this. It's the same motor that is used in the Collaro RC456, RC457 Autohangers. I think the one in your 4T200 might be bigger. It's certainly not a beaing problem. Ed Dinning's the man for anything that's wound, maybe he knows??!! Edward

[peter_sol]

Hello Edward
I had an identical problem and it was thickened old oil in the bearings.
The motor is an AC53.

[Audio1950]

I had an RC456 deck with the same problem. That turned out to be gunged-up motor bearings. I seem to remember doing something like boiling the sintered bronze bearings, but who told me to do that, and why?.......Anyway, it worked.

Barry

[starone]

Edward

I have a Collaro Conquest with the same problem. When I first got the player about 20 years ago the motor was completely seized, so I stripped it down and re greased etc. It was then fine for another 15 years, then it developed the same problem you're having. I don't use the player as much as I used to so maybe this has something to do with it. I never seem to have the time to have another look at it, instead I just let it warm up for a couple of minutes until it comes up to speed.

Martin

[Edward Huggins]

The bearings are fine and the heavy 10" pressed steel platter spins freely and, indeed, it takes along time to come to rest. When the motor is started it takes c. 20 mins to slowly build up speed to about 25rpm, then suddenly it "snaps in" to 33rpm and after that all is fine. Edward

[Techman]

I have to say that I'm still convinced that this is a bearing problem. There's a procedure for dealing with this when they're this bad which involves soaking for 24 hours - I think the procedure is documented on here somewhere. Personally, I think it's very unlikely to be anything to do with faulty windings as the fault would become worse with time. It's possible that there's some very obscure fault with the rotor, but unlikely, however, ready to be proved wrong.

I think this is the same motor as used in the Collaro tape decks of the time.

[Techman]

I've just had another thought - I think I once had a problem with the pulley slipping on the shaft. Worth checking to see if it's slipping when cold, but grips as the shaft expands. Even the shaft slipping in the rotor until it expands - that obscure rotor fault I mentioned above.

[stumted2]

Hi Edward,

I too have experienced this problem. I have serviced around twenty six Collaro decks so far, and have found the best way forward (for me) is to :

Remove the motor, remove the pulley, remove both top and bottom bearings, remove all felt oil pads, (two thin and two thick) thoroughly clean them with solvents to remove all traces of old (if any) oil, thoroughly clean and remove all traces of old oil residue from both top and bottom sintered bearings, remove the single small bearing in the bottom sintered bronze bearing, again thoroughly clean and remove all traces of old sticky oil, ensure the small bearing is free to move in the sintered bearing, (it should be freely able to move in and out of the bearing) clean the bottom bearing casting and remove all traces of old sticky oil (there is a small silver foil insert in the single bearing/sintered bearing cavity, remove all old sticky oil from this too.) apply thin oil (I use sewing machine oil) to all felt pads (don't drown them) slightly oil the top and bottom bearings and also the small single bearing in the bottom sintered bearing, ensuring that it is free to move in the sintered bearing, Clean the rotor shaft of any old sticky reside, very lightly oil the rotor shaft, reassemble the motor, lightly tap the completed motor casing in order to realign the rotor shaft with the bearings, refit pulley, check that the rotor is free running, refit motor, and all should be fine. (More than likely due to the fact that the motor is now warm.)

The acid test of course, is to leave the player in a cool place for a few days, and check again to ensure it's all still singing and dancing.

I know this may sound a bit like me like trying to teach granny how to suck eggs, and also a bit garbled, but I just thought I would share my Collaro experiences with any other forum members who may have experienced this problem.

Just an afterthought, the above does not relate to the motor type fitted to the Collaro tape deck.

Cheers,

Ted.

[Techman]

Good post, Ted.

[stumted2]

Hi Techman,

Many, many thanks for your very kind words, they are very much appreciated, and you've just made my day.

Cheers,
Ted.

[stumted2]

Just another afterthought on my first post, don't forget to remove all traces of solvents from the bearings and bearing oil felts. (I normally squeeze the felts between sheets of kitchen roll, and then dry them with my wife's hairdryer. (on cold setting) Hope she doesn't read this post, if so, in the words of that old song, "There may be trouble ahead".

Cheers,
Ted.

[Edward Huggins]

Thanks to stumted2 for all the detail in posts #10,12 and 13. Looks like I'll need to roll my sleeves up! Edward

[stumted2]

Hi Edward,
Wow, Many thanks for your very kind message.
I don't know if this is of any help, you probably know this already, but I've found the easiest way to remove the motor/stepped pulley, is to lightly hold the motor cooling fan, and turn the pulley anti clockwise and at the same time pulling it up.
When re fitting it, same again, rotate anti clockwise and at the same time pressing it down.

Just one other thing, in order to remove the cooling fan, remove the bottom motor bearing casting, place two short pieces of wood under the motor laminations (thicker than the rotor length,) ensuring that the rotor is not obstructed by the two pieces of wood, and gently tap the top rotor shaft downwards with a small brass or other soft metal drift which is slightly smaller diameter than the motor shaft, and will not damage it.
Once the shaft clears the fan bush, the rotor will drop out of the motor body.

To replace the fan, fully assemble the motor, then using a small hollow tube with a slightly larger inside diameter than the outside diameter of the fan bush, (I use a small box key) lightly tap it down, ensuring there is a small clearance gap between the underside of the fan bush, and the top bearing/casting. (about 1/16th inch) Also check that the fan blades are all in line with each other, and are clear of the motor casing.

Again, so sorry if this is a bit garbled, and you probably know this already, but just thought it may in some small way, help any other member, who may be tackling this for the first time.
Many thanks again for you kind words,
Cheers,Ted.