850 MKIII Swing Arm Grease Fitting?

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Hi Everybody,
Steadfast Cycles has a welch cap for the swingarm that has a grease fitting threaded hole. Question: does it make sense to fit this and pump my old swingarm full of new grease? I don't have a problem with excessive play , but it probably has been 45 years since it had its grease put in!
Sincerely,
Kara
 
You never use grease, the bushes are are sintered bronze which is porous and acts as a reservoir of the recommended oil EP140. The nipple is for either access for oiling by removal of nipple and using the hole for an oil can or applying oil via a grease gun. Grease blocks the pores and stops the bush lubricating the shaft, rapid wear follows.
 
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Mk3 factory fitted and lubed with wicks from new 33920 miles. Bearing dry and totally worn out with extreme play
Owner modified with nipple on welch plug and occasionally oiled 38507 miles. No discernable bearing wear.
"Sealed for life" is one of those infuriating marketing terms. Unless of course you reckon a Norton`s life to be 4 years.
Rick
 
"Sealed for life" is one of those infuriating marketing terms. Unless of course you reckon a Norton`s life to be 4 years.

I think what it actually means is sealed for the expected service life of the bearings as checking the swinging arm bushes for wear was part of the Mk3's routine maintenance to be carried out every 6,000 miles therefore not expected to last for the life of the bike (I'd guess there are still a few Commandos that haven't done 30,000 miles yet!).

I have a feeling the reason for going 'sealed' was mainly to prevent owners/mechanics from pumping grease into the pivot!
 
Hi LAB! I`m sure you are right about discouraging owners from pumping grease. But it also saved a drill/tap/ assemble operation, and that was evidently a high priority in 1975. The mk3 had many cases of 2 steps forward : and 1 back to save money.
I suppose a reasonable service life for a swinging arm bearing is debatable. Certainly not 6000 miles, and i felt aggrieved undertaking a major stripdown at 32,000. The fact that with an oil nipple the current bearing is lasting indefinitely convinces me that a nipple mod is worthwhile. It is possible , that my mk3 was never properly lubed at the factory in 1977. With a probably demoralised workforce, all under notice, maybe, and yet the overall quality of my Norton has been good.
If the OP does fit a nipple, it might be a good idea to fit a 3mm through bolt to capture the inner welch plug so it isn`t pushed out by the oil.
Rick
 
My '74 has a zirk fitting at the end of the swingarm. And I have a manual oil pump that looks just like agrease gun (Alemite 4035) . I was told there is a hex head bolt at the top of the swing arm you loosen so you don't blow out the seals pumping the oil in. But I find no hex head on the top or the side or anywhere but a small one right next to the zirk fitting and I figured that was to hold the cap on. Am I looking in the wrong place for it? And, I'm guessing 85 --140 is good.
 
You would be correct about Commandos out there that don’t have 30,000 miles. My ‘69 here.

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My '74 has a zirk fitting at the end of the swingarm. And I have a manual oil pump that looks just like agrease gun (Alemite 4035) . I was told there is a hex head bolt at the top of the swing arm you loosen so you don't blow out the seals pumping the oil in. But I find no hex head on the top or the side or anywhere but a small one right next to the zirk fitting and I figured that was to hold the cap on. Am I looking in the wrong place for it? And, I'm guessing 85 --140 is good.
Should be right in the middle on the top, under the front end of the fender. Kind of hard to get at with the wheel in place.
 
My '74 has a zirk fitting at the end of the swingarm. And I have a manual oil pump that looks just like agrease gun (Alemite 4035) . I was told there is a hex head bolt at the top of the swing arm you loosen so you don't blow out the seals pumping the oil in.

It's on the cradle tube, not the actual swingarm.
Item 22.
 
Sorry, it is actually forward of the fender. It is in the tube of the cradle that the swingarm spindle goes through. It threads into the spindle.
 
I run a constant feed from a 30ml bottle of 90 gear oil. It is connected to the centre bolt on my 850, and via the end plug on my 750. Now they are sealed for life. It does dribble out very slowly past the ö'ring. A small top up once or twice a year.
 
A CAUTION : IF you use a grease gun filled with oil and attach it to a Zerk fitting on the swing arm and pump the grease gun lever you can blow the cap off the opposite end of the swingArm/strip the threads on the long/thin screw that holds the caps in place. I have the T-shirt for that! :eek: SO if using that method, a gentle touch is in order! ;)
 
Great Idea Kerinorton! Everything should be easy if you're doing it right. I have oil coolers on my Norton's so this is just another plumbing job for me. The rear master cylinder reservoir on a T140 is mounted under the seat so something like that on a Norton to easily determine the level would be nice. I guess raising the height of the reservoir increases the oil pressure. If you have a moment, can you tell me where yours was mounted. Thanks, Jim
 
I run a constant feed from a 30ml bottle of 90 gear oil. It is connected to the centre bolt on my 850, and via the end plug on my 750. Now they are sealed for life. It does dribble out very slowly past the ö'ring. A small top up once or twice a year.
Please post a photo or two of this install.
Does this use a hollow bolt for feed location?

How can this lube system be adapted to a Mk3?


16SwingArmLubeCompare1.jpg
 
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Does this use a hollow bolt for feed location?

If you use an allen bolt with a hole drilled down its length instead of the original hex headed bolt then you have a round head for fitting a tube onto and a hole for the oil to pass through.
 
I run a constant feed from a 30ml bottle of 90 gear oil. It is connected to the centre bolt on my 850, and via the end plug on my 750. Now they are sealed for life. It does dribble out very slowly past the ö'ring. A small top up once or twice a year.
I do the same with my commando but mine leaks more than yours
I have top mine up more like once a month
 
FWIW, those are OilLite (or OilLite-type) bushings. They were developed (by Chrysler) to NOT require periodic lubrication. The lubrication is in the pores of the material and they do not benefit from 'constant' oiling. It doesn't hurt the bushings, of course, but they don't need it and it just leaks. If there is any dripping from the swingarm, there is too much oil in there. ;)
 
FWIW, those are OilLite (or OilLite-type) bushings. They were developed (by Chrysler) to NOT require periodic lubrication. The lubrication is in the pores of the material and they do not benefit from 'constant' oiling. It doesn't hurt the bushings, of course, but they don't need it and it just leaks. If there is any dripping from the swingarm, there is too much oil in there. ;)
I'm afraid I'm guilty of the other extreme
I once left my swing arm bushings un oiled for ages
The pin went rusty and wore out ,this was complete lack of maintenance on my part
Hence the paranoia on my part
I ride all year round and the winter road salt takes a heavy toll
 
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