Lubrication quetion for Harrison L5A

[rodger kalluParticipant @rodgerkallu82088]

I have a Harrison L5A lathe (1964). I have a persistent oil leak from the headstock main shaft just aft of the chuck. I have got a complete original handbook for the machine and looked at the exploded view of the chuck to see what sort of an oil seal I should replace. It does not appear that there is one?

Also looking through the handbook I can see no detail on what the headstock oil capacity is and where the drain is for draining the headstock if this is required.

All I can find is that the oil should be Shell Vitrea 72 or equivalent. This is a lot thicker that what I am using which might be part of my leakage problem?

[rodger kalluParticipant @rodgerkallu82088]

[not done it yetParticipant @notdoneityet]

Too thin oil may contribute, depending on the seal type. Other factors may be you overfilling, there may be too much bearing play, the seal may be damaged 

(or worn), or the seal bearing point on the spindle may be damaged (or worn).

 

 

There must be provision for draining the headstock and usually some form of level device. Doubtless the drain will be at the lowest level of the box and the upper level device may be a dip stick or level plug. Both should be fairly easy to find by observation.

 

 

Do tell us the seal type.  Is it a lip seal, felt seal, or other?  Lip seals require a good sealing contact point, but can be displaced slightly to use a different sealing point on the shaft.  Felt seals usually have a thrower to prevent direct and continual immersion of the seal in oil.  Some seals do not have any seal, per se, but actually 'screw' the thrown oil back towards the gearbox.  

     

 

The last, but not least, reason for leakage may be a blocked breather, causing a pressure difference between the interior and exterior of the headstock.

 

 

 

 

 

 

 

 

 

 

 

Edited By not done it yet on 25/07/2016 06:41:23

[Phil PParticipant @philp]

My L5A has a sight glass on the back of the headstock for checking the oil level.

I do know that the thinner the oil, the noisier it gets. I tend to use straight SAE 50 engine oil in mine with a generous dollop of Lucas oil additive for good measure. It does need to run a while to warm up in winter before the higher speeds can be used.

The purists will probably disagree, but it has been run like that for the last 25 years with no bother.

Not sure about the seal as it is 25 years since I replaced the bearings and I cannot remember.

Phil

Edited By Phil P on 25/07/2016 07:05:23

[KettrinboyParticipant @kettrinboy]

Ive got a 63 L5 and at the rear of the headstock there is a combined filler and drain cock with a level sight glass , the drain screw is an allen grub screw in the bottom of the cock , the main spindle front seal is a labyrinth type on mine so maybe a thinner oil is more prone to leaking , i recently changed my headstock oil for a 68 weight oil which is around 20/30 SAE in place of the thicker old oil and now i have a slightly bigger leak than i had before from the input shaft that the clutch sits on but i will live with it , the front main spindle seal is still fine though , Harrison is now owned by the 600 group so from what ive heard on other forums a new spare if available wont be cheap..

regards Geoff

Edited By Kettrinboy on 26/07/2016 07:57:40

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