Myford Gearbox drain seal washer

Gents,

Our gearbox is leaking and I have a feeling its leaking at the drain plug. I have a rubber o-ring on it now but that hasn't really helped.

According to the parts list, this part is called a Dowty Seal I have contacted Myford and they don't have them.

Does anybody here know where I could order one of these?

Thanks,

Mark

Mark,

A quick search on Google revealed many suppliers:

This is one with good documentation: **LINK**

http://www.barnwell.co.uk/products/bonded-seals/

MichaelG.

.

This is also worth a look: 

http://www.potterassoc.com/pdf/bonded_seal_information_and_sizing_chart.pdf

Edited By Michael Gilligan on 08/11/2018 13:12:43

Michael,

Many thanks, I should have turned to my Google fu before asking! I have asked Myford for the appropriate size and will order 1 or 2 from Barnwell.

Thanks again,

Mark

Hi Mark you can pick these up from any hydraulic hose repair shop "phone a hose" or similar cost very little. Just take the plug with you and they will give you corect washer.

David

Edited By David George 1 on 08/11/2018 13:22:13

Ok thanks David

**LINK**

Goodridge have them.

Mike

Mine leaks so much i assumed it was supposed to... what size does it take?

If an agri repair shop is nearby, they would likely stock them. Not as cheap as a belt/bearing supplier, perhaps, but might save you more in fuel... I use ABC for most of my bits and pieces like that.

The part where the seal sits measures 7/16 so I had to guess a metric equivalent as I am in the Netherlands.

Are you sure that's the correct size, Mike?

Make a soft alu or annealed copper washer either should stop it.

A Dowty seal (washer) is a steel washer with a double sided elastomeric rubber seal bonded to the I D. Rather like a lip seal on both sides of the washer.

Should be available from all sorts of sources. (Agricultural, hydraulic hose suppliers etc)

Howard

There is a dropdown box on the link to select the size required.

Mike

Copper or aluminium sump plug washer from your local car parts shop will do the job.

Mark, are you sure it is leaking from the drain plug? I had a leak on my gearbox which came from the hidden captive screw which is inside the box, this hidden screw has a rubber washer between the box and the lathe bed and that was where my leak came from, looking at the front of the g/box at the bottom left hand side there is a screw plug which  has to be removed to let you get to the hidden screw, but sadly the g/box has to be removed to replace the rubber washer, on Myfords drawing of the g/box the drawing numbers of the parts are 136, 137 and 138 (hope this is of some help)

Peter

Edited By Flywheel on 09/11/2018 08:57:17

Peter,

No, I am not sure and that is also a possibility, many thanks! As a precaution I have ordered 5 of those rubber 0-rings (BS / USA size 11 which is a 7.65mm ID, a 11.21mm OD and has a material thickness of 1.78mm). I am going to try and seat the washer without removing the 'box

Mark,

It is a lot of work to take the gearbox off to fit a pesky new 'o' ring in such an awkward position.

From the Myford gearbox drawing, screw # 136 is said to be captive and looks to be waisted down the length below the head to the thread. It also has a 1/4 inch spring washer to help lock it in place

Two possibilities occur to me

• The bolt is loose enough for oil to escape
• You can unscrew it, remove the spring washer and fit a plain washer below the head with a rubber seal cut from a thick tap washer below it as a good fit on the bolt shank and close the leak off from the inside

You might save a lot of time and refitting nausea by trying those suggestions.

Regards

Brian

Brian, good idea. I was under the impression that the o-ring fit on the inside of the ‘box. The drawing shows otherwise as I see now. Bugger,

I will try your suggestion. I ordered the o-rings anyway so will try and wangle a solution using them.

Thanks again,

Mark

Hello Mark,

I suggested a thick neoprene washer in particular as that will have better resilience and gap filling properties than an 'o' ring in a open situation between a washer and the gearbox housing inner surface. It may not even be machined at that point as the sealing is intended to be done by the 'o' ring sandwiched between the outer of the gearbox and what was once the mounting face for the leadscrew bracket.

The spring washer locking the bolt on the inside may also have left a rough surface to seal against, another challenge for an 'o' ring to try and overcome and a further good reason for something more rugged

This is just the approach I would try in your situation

Regards

Brian

Brian,

Understood. I’ll give that a try and report back. Thanks,

Mark