#52 oil bath motor HMV 202

[saxymojo]

Hi

I just purchased an HMV 202 with the #52 two spring oil bath motor, I have never pulled one of these down before. Upon discovering that the motor had no oil, I decided to have a look.

I was told not to grease the springs although they definitely were greased in the past, and to fill the sump with transmission fluid to a level below the governor. Can anyone that has done work on these machines confirm this for me or have more advice?

Update. I found one spring was greased the other was just oiled, the greased one was dried out graphite and grease mixture.

Regards Marcel

[epigramophone]

A useful article on the No.52 motor appeared in the CLPGS magazine No.33 Spring 2010 issue. This is of course subject to copyright, but if you know any CLPGS members in your area you will find it worth reading.

As you will have discovered, there is a hand operated pump which distributes the oil to the bearings and governor, but only a service manual (if one ever existed) would indicate the grade of oil to be used.

I would advise against the use of any transmission oil containing Extreme Pressure (EP) additives, as these can be harmful to Phosphor-Bronze bearings. I do not know whether the No.52 motor is fitted with this type of bearing, but it is not worth taking any chances.

[gramophoneshane]

A useful article on the No.52 motor appeared in the CLPGS magazine No.33 Spring 2010 issue. This is of course subject to copyright, but if you know any CLPGS members in your area you will find it worth reading.

I have to ask, but useful in what way?
It obviously doesn't state the oil grade to use, nor the bearing type/s used, so is it really "useful" for a No.52 owner, or more a general interest artical for the casual collector?
I suppose it might state the amount of oil thought to be used, and how often it should be distributed around the motor, but surely that information could be shared without infringing upon any copyright laws?

[gramophoneshane]

Marcel,

I've never pulled a No.52 down either as my 202 isn't a 202A, but as it was loosely based on the Garrard Super motor, I'd imagine they would have used the same type of oil which was distributed in a similar way.
Unfortunately I've never found any original data for either motor that states oil types or amounts.

As far as I'm aware, the only real difference between the two motors is that the Garrards pump is activated whenever the crank it turned to wind the springs, and the HMV's pump is manually operated.
In the Garrard motor, oil from the sump is drawn up a tube and released into a reservoir in the top casting of the motor. Narrow creeks run off the reservoir so that oil can reach small pools around each of the top bearing, and small holes are drilled so the oil can feed the bearings & drain away fairy quickly. The reservoir has a nickelled cover plate that is easily removed for oil top-ups & to prevent any foreign matter entering the motor.

When I pulled my super motor down, the springs were only lightly greased, I think because oil runs down the spring barrel pinion, allowing a small amount to enter the spring barrel, so I assume it was enough to to keep the springs wet, but not enough to wash excess grease from the barrel into the sump?
I have no idea if the same applies to your motor though.

If only one spring in your motor was greased, I assume the springs are in separate barrels, and the top spring barrel contained the grease?
That would indicate to me that the bottom spring relied only on oil for lubrication, so the oil level would have to be high enough for at least part of the bottom spring to be constantly sitting in oil. Perhaps half way up the bottom barrel might be a good level to aim for?
Personally, I think you're better to have a little too much oil than not enough, and as long as the bottom spring is getting oil, and the oil isn't high enough to interfer with the spinning of the governor, you should be pretty safe.

I too would be hesitant about using transmission fluid, partly because you don't know how it may react to the different metals & gaskets of the motor, but mostly because it's probably nothing like what was used originally
For my Garrard, I just used a full bottle of Singer sewing machine oil, as it is light enough to be drawn up by the pump easily & flow around the motor as I suspect it should, plus it was the right amount to fill the sump to the level I assumed it should be. Although transmission fluid would certain circulate in much the same way and may not cause any damage, a gramophone motor won't be exposed to heat or stress like a transmission, so I think some sort of light household oil will be sufficient.
Unfortunately, unless some sort of instructions or service data can be found, all we have to rely on is guess work

BTW: Be sure to check the rubber plunger/grommet/flange thingy in your pump too. It would have probably perished to some extent by now & will need replacing.

[emgcr]

With regard to the Garrard Super Motor, I have found that to overfill with oil is a mistake as the result is the leeching out of the (Moly) grease in the spring barrels---the oil combines with the grease and quite quickly forms a stiff sticky mess which starts to gum up all working parts but leaves the actual springs dry ironically. 100 Ml is the amount which seems to be about right after much experiment---just covering the lower gears. Singer sewing machine oil or 20w/50 motor oil both seem to work well but not "three in one" which has a tendency to dry out.

I am afraid I have no experience of the HMV equivalent but imagine similar principles might apply ?

[gramophoneshane]

100 Ml is the amount which seems to be about right after much experiment---just covering the lower gears.

I'm happy to hear that because a bottle of Singer oil (here) is indeed 100ml. Guess I can get it right some of the time

[Swing Band Heaven]

Hi Marcel,
a while ago I picked up a copy of original instructions for the 202 /203 which includes information on lubrication of the oil pump motor. In actuality it doesn't say much other than generalities but it does state oil quantity (provided you know the size of an HMV oil bottle) and it does say how often to lubricate - all without infringing any copyrights . Unfortunately I don't have it to hand although I have scans of it which are larger JPEG files rather than PDFs. If you'd like me to email the whole thing to you let me know. Below are some of the pages.

[saxymojo]

Hi

Thanks for all the replies, I finished servicing the motor about an hour ago. I also thought that Singer sewing machine might be better than transmission fluid, I have a few industrial sewing machines here that are oil bath, so I have plenty of oil on hand.

I decided to oil the springs rather than grease them, the springs are beside each other so I can't see any reason that one was greased and not the other. I will keep a close eye on them to see if the oil gets into the barrel. These motor are very easy to pull down and the spring barrels are very easy to open.

With the amount of oil, I have no idea how much to use, so I have filled the sump to just above the oil reservoir, I though this might be the best idea, over filling the sump could cause oil to leak through the crank entry point. I replaced the leather seal at the crank entry with a rubber O ring, this should stop any oil leaking.

I have attached photos taken prior to cleaning the motor.

Regards Marcel

[gramophoneshane]

Thanks for posting those SBH. It's interesting to see some of the differences between your instruction book, and the earlier book for "Improved spring driven models".
I'm just curious, but does the setting up machine section mention whether the new owner had to add oil to the motor (perhaps a full bottle), or can I assume they were shipped from Middlesex with oil already added to the motor?

And Marcel,
Thanks for the picture. I've only ever seen pictures of the bedplate sitting on the motor board before, so it's nice to take a peek inside
The casing appears to be about the same size, or perhaps a little larger than that of the Garrard.
I'm just wondering whether both springs should be greased, and if at some stage the motor had been overfilled so the grease from the bottom spring was washed away as in emgcr's example above.
I suppose the best you can do for now it check the springs regularly to make sure they are getting lubricated properly.

So now that you have both a 202 & 193 side by side, can you hear a marked improvement in sound quality from the 202?

[saxymojo]

Hi Shane

Apparently they were shipped dry and supplied with a bottle of oil, just the right amount for the new owner to pour into the motor, now I need to find out what that amount was.

Regards Marcel