Thread: Overdrive dog lubrication?

Just looked it up. Believe it or not, the Fairey installation instructions do not even tell you to lubricate it!

I have an overhaul manual written by Ulrico Becker, and he recommends using MoS2 grease or consult your local bearing company for a suitable long lasting grease.

When installing mine I used MoS2 grease. I suggest that it would be a good idea to remove the unit and regrease as necessary every couple of years.

John

Thanks JDNSW, I noticed the manual didn't tell you to lubricate it, but they did say to make sure you didn,t remove whatever was there originally.

Cheers, Mick.

Hi Killer
Its the same oil as the transfercase.
They use the real small reservior up quickly,normally lost into the transfercase.This causes overheating and death of the overdrive.
I met a Series Pilot who devised his own fix,he cut the bottom off an empty overdrive then welded a much larger sump on.A simple solution to a common Fairey problem.The Fairey now runs cool and doesnt force its oil into the transfercase when hot!!!!
WORTH CONTEMPLATING!!!!
Andrew

Originally Posted by LandyAndy

Hi Killer
Its the same oil as the transfercase.
They use the real small reservior up quickly,normally lost into the transfercase.This causes overheating and death of the overdrive.
I met a Series Pilot who devised his own fix,he cut the bottom off an empty overdrive then welded a much larger sump on.A simple solution to a common Fairey problem.The Fairey now runs cool and doesnt force its oil into the transfercase when hot!!!!
WORTH CONTEMPLATING!!!!
Andrew

A breather on the tin plate with a length of hose helps here, I hear a lot of blokes with Fairey O/D carry the original drive gear in case the fairey drive dog fails, and going by the dozen or more that I have looked at lately it is a real good idea, Regards Frank.

Originally Posted by LandyAndy

Hi Killer
Its the same oil as the transfercase.
Andrew

I read the question as being much more specific. The drive dog, being inside the quill shaft is not exposed to either the oil in the overdrive or the oil in the transfer case (although it is open to the transfer case), and so relies on the lubrication it is assembled with. I have seen suggestions that holes be drilled to allow oil in there, but I haven't seen it done.

As far as the general lubrication of the overdrive goes, I have extended the breather up to reduce the amount of the oil it chucks out, and I would note that the instructions require weekly oil level checks.

John

The question was as JDNSW understood it, which related to lubrication of the dog itself upon assembly. Mine also has an extended breather, (an inline fuel filter stuck on top of the inpection plate) and oil use is negligable.
Thanks for the replys fellas, I appreciate your comments.

Cheers, Mick.

Originally Posted by JDNSW

I read the question as being much more specific. The drive dog, being inside the quill shaft is not exposed to either the oil in the overdrive or the oil in the transfer case (although it is open to the transfer case), and so relies on the lubrication it is assembled with. I have seen suggestions that holes be drilled to allow oil in there, but I haven't seen it done.

As far as the general lubrication of the overdrive goes, I have extended the breather up to reduce the amount of the oil it chucks out, and I would note that the instructions require weekly oil level checks.

John

John, every Fairey Drive dog I have seen is lubed from 3 to 4 holes drilled through the base of the teeth on the main gear drive, which is supposed to lube the roller bearings on the drive dog, going by the chatter marks on ALL of the main gear inner race (where the drive dog rollers run) that I have seen, it seems this oiling system is not very effective, maybe why it is recommended that a long lasting grease be used, Regards Frank.

Originally Posted by Tank

John, every Fairey Drive dog I have seen is lubed from 3 to 4 holes drilled through the base of the teeth on the main gear drive, which is supposed to lube the roller bearings on the drive dog, going by the chatter marks on ALL of the main gear inner race (where the drive dog rollers run) that I have seen, it seems this oiling system is not very effective, maybe why it is recommended that a long lasting grease be used, Regards Frank.

The oil holes get oil onto the roller bearing reasonably well - but they don't get it onto the next layer in, the dog itself, as shown by the rust and wear on the ones I have seen. I suspect the chatter marks you see may reflect long periods of use in direct drive, with the rollers on the same spot (if you think about it not a very good situation for roller bearings - c.f. the discussions on free wheel hubs), rather than lack of lubrication - although I could be wrong!

John