Hoover Twin Tub: Will the Resilient Bearing's rubber tolerate petroleum-based grease?

[wishywashy]

Good Evening Folks, and friendly regards to all!

This afternoon I decided to give my T1302 a little long-overdue exercise, during the course of which it decided to screech its head off at me during the spin-cycle...
This is apparently a fairly common predicament with these machines, and lubrication of the sleeve-bearing that sits in the rubber "Resilient Bearing" underneath the Spin Can seems to be the obvious solution. But before leaping into the procedure, I thought it would be wise to first ask whether anyone knows for certain if the rubber that the Resilient Bearing is made of can tolerate petroleum-based grease without either cracking or breaking down into goo over time...?

Any general comments or tips on the subject of lubricating this particular bearing would also be most welcome. Perhaps someone has a copy of the relevant page from the Service Manual for this machine...(?)

Many Thanks in advance,
WishyWashy

 

[keymatic3203]

Hi Wishywashy

as it's the brass bush you would be lubricating then any grease suitable for that would be ok, as it wouldn't be in contact with the rubber of the mount anyway. If your not going to strip the unit down and grease the shaft, then a quick second best would be to turn the machine over and work some cycle or bearing oil into the bearing. I would say if you've not got time for a more thorough service, then a good oiling would be preferable to running the bearing dry and will stop the screeching. Wiping any excess oil off the mount would obviously help and some silicone lubricant spray ( such as for upvc door and windows, generally says it's safe for rubber seals etc, if you have it over in australia 3 in 1 brand does a silicone spray), would be good to help keep the rubber part soft and flexible.

All the best, keep enjoying your hoovermatic

Mathew

 

[triumphtoledo]

rubber grease

Would not rubber grease be ok? It won't rot the rubber but would it be OK for the bearing?

 

[wishywashy]

Hello Gents, and thank-you for the replies...

Matthew - The trouble is (at least as far as I can see), it wont be very easy to stop the grease from squeezing out onto the surrounding rubber surfaces. This is because the upper surface of the Resilient Bearing is hidden from view by the Spin Can as soon as it is placed inside the Spin Tub in any attempt to reinsert the Spin Can's shaft through the sleeve-bearing in question. So, if the Spin Can's shaft is lubricated, then you can certainly expect some hidden-from-view "wipe off" of grease from the shaft onto the upper edge of the sleeve-bearing to occur as the Spin Can is driven home. This would surely ooze out sideways onto the Resilient Bearing's rubber, because the opposite mating surfaces of the underside of the Spin Can and the top of the Sleeve Bearing, would presumably be very important to lubricate too. And with the Spin Can in the way, you wouldn't be able to wipe or wash this grease off the rubber again...

At the underside of the Resilient Bearing, it is a similar story, but not quite as well hidden from view. The problem here is that the Spin Pulley has to be already mounted in place before the Spin Can is reinserted, because the shaft of the latter fits inside the shaft of the former. But this means that "squeeze out" of grease between the mating faces of the two components can ooze out onto the Resilient Bearing's rubber where it surrounds the sleeve - hidden from view by the top of the Spin Pulley's shaft...

So all in all it's not a straightforward situation. We're not talking about a lot of grease, but squeeze-out will ensure that it's nonetheless plentiful at the delicate edges of where the Resilient Bearing's rubber grips the sleeve-bearing at both the top and the bottom...

I've tried that Silicon Spray you suggested, by the way. I bought it a while back to do the suspension bushes on my chariot, and it's not too bad in that application. As far as the twinny goes, I've used it on the Pump shaft, with the machine upside down and the little pump-pulley removed, and it seems to work quite well there too, by drawing itself down the shaft into the housing. But alas - with regard to the Spin Tub, the silicon spray just doesn't seem to stop the screeching permanently. There's been times when I've thought that it has, but the screeching has returned even louder the next time I've tried to use the machine...

Triumphtoledo - thanks for the suggestion regarding the Rubber Grease; I didn't even know that the stuff existed! I've been using an American product called Rubber Renue to treat old rubbers with. It stinks to high heaven, because it is basically methyl salicylate (ie. like Dencorub or Deep Heat or Wintergreen Oil) in a liquid solvent. But although the fumes are hard to take, it does have one significant advantage over gels or pastes, and that is it's penetrating power (due to being in liquid/solvent form...) I'll look out for that Rubber Grease though, because it would certainly have its uses. But as you have already alluded, it's abilities in a high-speed bearing situation - with incumbent temperature and pressure - may be limited...

Best Wishes for now,
WishyWashy.

 

[keymatic3203]

yes I do see what you're saying

though from my years experience of these machines, the rubber has either dried out and perished or the bearing seized and ripped the rubber where the bellow fold is. So whilst your right in considering the damage from the grease getting into contact with the rubber, though the rubber is at it's thickest surrounding the bearing and from memory if I'm right the triangular earlier resilient mounts had a cast aluminium insert within the rubber to hold the brass bush. I still say in my view the order of importance would be first for the bearing to be lubricated then for the rubber not to dry out either through regular use, or with products such as those mentioned above.

As for the surfaces of the shaft seal, as I've always understood and done with many machines, they should just be cleaned with meths or similar and not lubricated, the carbon surface being self lubricating.

mathew

 

[wishywashy]

Thanks again Matthew, and roger on all of that. Carbon hey? Yes, makes sense... I'll certainly look out for such surfaces when I get around to pulling the thing apart. It's not easy to get a really good look at the Resilient Bearing close up, because by this stage of the machine's life, the rubber is getting old enough to make its removal from the bottom of the Spin Tub fraught with danger(!) And you can't glean much from the Exploded Parts Diagrams for them that you see here and there on the Net, because they are very low in resolution, and hence quite difficult to make any meaningful deductions from. Heaven knows how many perfectly good Service Manuals for them have been thrown away by retired repairmen over the years...

Well, all the best for now,
WishyWashy.

 

[wishywashy]

By way of an update Gents, I got through on the phone yesterday to a very helpful technical chap at Nulon (an Australian-based motor-oil manufacturer), in order to ask whether the particular grease they sell was safe to use on rubber. His reply was that it was mainly just natural types of rubber that were prone to attack by petrochemical products, and that the Resilient Bearing in the Twin Tub was most likely made of something synthetic instead - like nitrile - which is apparently quite resistant...

This makes sense, because I have read on motoring forums here and there that DIY mechanics have good success working with grease and oil when they use those disposable nitrile gloves that are sold in tissue-like boxes. This contrasts with my own experiences with some disposable latex gloves (which is a natural compound) that I bought from Aldi, which are totally useless with anything petroleum-based. As a matter of fact, it was mainly my experiences with pair after pair of the latex gloves falling apart after using them with grease and oil that got me so worried about getting the grease onto the Resilient Bearing's rubber. I was totally caught up in thinking that only Viton seals could resist petrochemicals, but apparently not so...

So there you go. Your views on the subject turned out to be quite sound Matthew.
By this time tomorrow I will have a screech-free Twin Tub...

Many Thanks & Best Wishes,
WishyWashy.