Help identifying "garter type" oil seals

It seems I need to replace the "garter type oil seals" (as the MEW restoration article author describes them), for the oil bath power feed gearbox shafts that pass through the cast iron body into the oil reservoir, on my Senior M1 mill.

However a google search has failed to bring up anything with the "garter" label. Hence can anyone suggest what are the correct seals I need, obviously imperial sizes. I'm new to all of this!

All you need are the three dimensions of the holes shaft and depth, and you can try "bearing boys" or even ebay for the size. Most oil seals are garter type, it refers to the spring which holds the lips tight. Another good source would be "simply bearings"

Edited By old mart on 11/07/2020 15:16:34

Try ‘goggle’ again/. First hits are for that type, amongst others.

Try looking for ‘lip seal’,the garter bit refers to the spring inside it I think. Just had one from ‘Simply Bearings’ for a water pump

Since the seals are for temperatures not too far from ambient, I would suggest Nitrile as the material. It is the norm for I C engines, so should be good for over 100C Silicone rubber,(red ) remains more flexible down to temperatures as low as - 40 C but you won't be expecting to work in Antarctica, hopefully!

Fitting tips

DON't touch the lip

Cover any threads or keyways with masking tape, to protect the seal as it passes over the shaft

Don't fit the new seal so that runs on the area worn by the original. Position it slightly away.

Put some oil on the shaft where the seal is to run, before fitting, so that it does start up dry and wear.

Howard

Just to fill out the good advice that's been given...

Oil seals are a tight fit into the bore that receives them and can be difficult to get started into the bore. Make up a simple tool ensure that the seal is pushed or pulled into the bore without being cocked over. For an application like this, a seal without a spring would be OK, and either a single- or double-lip seal would be fine, as long as the axial length was correct.

In this application, the seal is keeping oil in, therefore the lip side of the seal should face the oil. If the aim were to keep muck out (as in a wheel hub), the lip would be on the outer face. It's not uncommon to find wheel hubs in which 'mechanics'(?) have installed the seals the wrong way round...

Take and follow mnfrs. advice. Some modern material seals must be fitted bone dry. Land Rover timing cover/crankshaft seals since at least 2005 are one example.

This link should show most of the common types:

**LINK**

The oil seal in a vehicle hub is to keep the oil/grease in, when it gets warm and fluid. This saves it from escaping to lubricate the brake linings. Slippery linings are not a good thing.

'mechanic'(?)

I agree totally with Watford.

I have never seen a road vehicle hub where the seal is fitted with the lip facing outward. If dirt ingress is to be prevented, two seals would be fitted with the inner one lip in to seal the lubricant in, and the outer lip out to exclude dirt.

This is intended for machines operating in a dusty environment, such as construction machinery.

Many seals incorporate a wind back thread on the lip, so fitting the wrong way round will cause leakage!

We had a batch of reverse rotation marines where, erroneously, standard seals were fitted . The error became apparent as soon as the engines fired!

A similar arrangement is used to seal shafts on fuel injection pumps. Fuel does not leak into the sump, and lub oil does not find its way into fuel system risking engine run away.

Howard

Watford and Howard Lewis are of course correct, where road vehicle hubs are concerned, when the primary purpose of the seal is to contain lubricant. However, my comments were about seals in general, and were not restricted to those in road vehicles. There are many applications in which the seal's primary purpose is to exclude muck, and allow grease to pass, for example, tractor front hubs and grass-mowing equipment, to name but two, in which said hubs are of non-driven and non-braked wheels. In these, the operator is instructed to pump grease into the hub until it exudes past the seal - the hub cavity is grease-filled, and it never gets hot enough to pass the seal in use.

TEFC electric motors also commonly have the seals installed with the seal lips outboard.

It is unfortunate that my implied criticism of 'mechanics' is justified: it is not uncommon to find that seals have been replaced incorrectly, possibly because the replacer adopts the all-to common attitude that anything outside his personal experience must be wrong, so he puts the seal in his 'correct' way round...

When I did the modification to the Tom Senior light vertical fron MT2 to R8, I included a double lip seal into the design to run on the end of the spindle adjacent to the lower bearing. It was a double lip seal with a garter spring on one side and a thin unsprung lip on the other. I removed the spring and fitted the large lip on the greased bearing side. Every time the spindle was tested, it overheated and I spent some time fine adjusting the bearing preload, even setting the quill and spindle assembly in vee blocks and using a dti. I eventually realised that the bottom bearing was getting hot and the top one wasn't. The heat was being generated by the oil seal, even though the seal size and shaft matched and it was well lubricated. The only cure was to cut away the upper part of the seal entirely which was ok as there was grease not oil and rely on the outer lip. The outer lip is satisfactory as it does not heat up and is present solely to keep swarf and dirt out of the bearings.