HMV 157 Spring

[Dave Cawley]

My HMV 157 is in excellent condition but ever since I have had it, it will only pay ¾ of a 12" before running out of steam. It belonged to a professional old man who had probably not played it for 30 years or more.

What are my options ?

Thanks

Dave

[Phono48]

The 157 uses the No.32 double spring motor. The springs were lubricated with graphite grease, which, if the motor hasn't been overhauled, will have solidified. The usual sign that this has occurred is a loud "bumping" noise as the springs unwind, which is due to the coils of the springs sticking together. The springs need to be removed, cleaned and replaced with fresh grease. Not a job to do yourself if you have never taken a spring out before, as they can be dangerous things to mess about with. If there is no-one locally who can do this, I will willingly do the job, no charge, while you wait, but I'm in Peterborough, a fair way from you. If interested send me a PM, and we'll go from there.

Barry

[Dave Cawley]

Hi Barry

Many thanks for that.

I'm not up your way for some time. Thanks to your suggestion I then found the YouTube video on how to do it. I am good at mechanical engineering and with gloves, safety goggles and a safety hat, I'll attempt this soon. I'll report back.

Many thanks

Dave

[Dave Cawley]

Two years later I have it apart. The grease is all but solid !

I'll have them ultrasonically cleaned tomorrow.

There is a guy on YouTube, he may be here, that recommends packing a lot of grease into the springs as well as a dose of Slick 50 ?

I'm not sure of the philosophy here. Is is the grease stop them rusting, to ease their way, or to provide damping ? or ??

So given the choice, what and how much should I use ?

Thanks

Dave

[JerryVan]

Dave,

You don't necessarily have to have them ultrasonically cleaned, (though that would do a good job). You can scrape the dried grease off with a putty knife and wipe the springs down with a rag soaked in paint thinner, or kerosene, or some other solvent of your choosing.

Before you remove them, take special note how each is wound, with respect to a R.H. or L.H. spiral, or clockwise, counter-clockwise if you wish.

As I re-insert the springs, I wind in a few turns then, with a spatula, smear in a gob of grease. Repeat until the spring is in. Then fill ½ - ¾ of the remaining volume with grease. The grease is not meant to damp the action of the spring, or necessarily to prevent rust, (though that's not a bad thing to prevent), but instead is simply meant to lubricate the spring, allowing the layers to slide against each other as the spring unwinds.

As a side note. The problem you have with lack of power is not always due to dried grease. You may ultimately find the springs have lost their temper and may need replacement.

[Phono48]

The above advice is very sound. No need to worry about the direction of the springs - the barrels have a lip riveted to the side, and the springs have corresponding "hooks",so they can only go in one way.

[Dave Cawley]

OK, thanks. I photographed everything as it came apart so it will go back the same way.

Intuitively I can't see the need for so much grease, but I will bow to superior knowledge and experience ! They are almost solid so I hope that's the issue.

Hopefully I'll report back success in a day or two.

Thanks

Dave

[Phono48]

It's very much a case of personal choice how much grease you use. I put a couple of big dollops in the bottom of the drum before starting to wind the spring in, and then another couple on top of the coils when it's all in place. The grease will get distributed around the coils when the spring is wound. The problem with putting too much in is that the excess will ooze out through the centre shaft, and end up all over the motor and the cabinet.

[Dave Cawley]

Thanks, all the parts are soaking in a degreaser round the corner from me right now. It was so hard that it was almost solid.

I'm going to put some thin lithium complex grease in this evening. It looks and feels right, and is a great transparent red ! Stiff grease is going to take power out of the spring.

Can you tell :

https://www.youtube.com/watch?v=60P1xG32Feo

[Dave Cawley]

OK, all back together and almost perfect ! A hard job though..............

Two questions :

1. How long should it maintain speed for when wound up ?

2. There is a rumbley muted rattle from the regulator, barely audible with the lid shut ? Is this normal, if not what is causing it ?

Too late to investigate now as it's UK beer time !

Thanks

Dave