I wonder if it is useful to put some grease into the bearings of a Hoover. Or should I just leave them like they are? I think some of it would not be too harmful (brush roll bearings, motor bearings = the lower is a ball bearing, the upper one is just a bushing). If so, which might be the best brand? Thanks all. Joe
Post# 72597 , Reply# 1   6/21/2009 at 12:46 (5,421 days old) by tristar ()  
If they're noisy, pull them out and soak them in paint thinner overnight. The next day let them dry out for a while, then pack them with grease. Standard wheel bearing grease is fine, or if you prefer, lithium grease. If you've got a particularly old bearing that's "screeching" and you can't get it to stop, try using Molybdenum grease. It's known as engine assembly lube.....just be careful....it gets on everything! Did I mention it's permanent?
The one type of bearing you NEVER EVER want to grease is a bronze sleeve bearing. Or any sleeve bearing for that matter...... Grease will ruin it permanently.
If you want to lube up a sleeve bearing, get some detergent-free motor oil. Put some on a cotton swab and clean out the bearing first, then put several drops in the bearing and allow it to sit so the bearing soaks up the oil. Wipe up the excess and reassemble. For good measure, I usually wipe the shaft with oil before reassembly. If you do that to a sleeve bearing and keep it from drying out, it will last indefinitely.
Post# 72600 , Reply# 2   6/21/2009 at 15:11 (5,421 days old) by whirlpolf ()  
hey Eric, that is more than detailed. Thanks so much. Actually, the upper one is some sort of a bronze sleeve. Good that I have both grease types in my house (molybdenium and plain bike oil). I will follow your advice. Will tell you if "purring like a cat" happens. Thanks again. Joe
Post# 72602 , Reply# 3   6/21/2009 at 15:47 (5,421 days old) by tristar ()  
If it's purring you desire, take the lower motor bearing out and soak that sucker in solvent. Be sure to swish it around every so often to move the sludge around. You'll see a bunch of nasty black crumb looking stuff come out of the bearing. That's the old dirt and SKANKY grease that was in there! Pack the bearing nice and full of the highest quality grease you can find and rotate it through several revolutions, then clean up the excess. You may need a thin screwdriver to force the grease down into the slits between the grease shield and the bearing races. It's a lot easier with the proper grease gun fitting (which I have yet to find), but it's doable with patience and good lighting if you don't have it.
Some Hoover bearings have felt seals in them. Remove the felt before you soak it in solvent. If it's a Convertible/Senior style bearing, it probably doesn't have the felt.
I've recently sent off the bearings from my 150, 25, and 28 to be professionally serviced. The bearings were too far worn to be repacked by hand, and they've all been NLA for quite some time. I sent them through several solvent baths over several days, cleaned with abrasive sand, then flushed thoroughly and mailed them off to be injection packed by a friend/shop-owner who happens to have the proper grease gun for those old bearings! I'm hoping to get my own cat-purring when they come back to me next week!