Re-packing belt tensioner bearing grease suggestions?

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wylie's pup
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Re-packing belt tensioner bearing grease suggestions?

Postby wylie's pup » Fri Apr 09, 2010 12:28 am

I'm the type A guy that can make anything complicated. My current situation forces low buck solutions. First I pulled the seals, cleaned the bearing in the parts washers and repacked with Mobil 1 synthetic grease. The bearing had a lot of drag. I set it on a heater to see if that made a difference, it didn't. Looked online, it has a "stiffener" in it. Afraid to use that, so I go to the parts store, not a chain and ask the guy behind the counter if he knew anything about grease. I didn't want to use any old grease, this had to be special grease. He acted like he knew just what I needed. I walked out with moly. I've always hated palm packing bearings and the fact that this bearing is 1 1/2 thick it holds lots of grease. After the moly can hardly turn at all. So once again I go online and find....................."If you are lubricating a wagon axle any grease will work fine. Moly greases are very good in slow speed applications where the clearances are 0.002 to 0.005.
As you know the moly works into the metal surfaces and provides enhanced lubrication when there is the potential for metal to metal contact. The reason moly is NOT recommended for ball bearings is because the moly can build up on the race surfaces and reduce the bearing clearances enough to cause bearing failure. Some years back the Model A Ford club recommended a moly grease for the rear axle ball bearings. There was a rash of axle bearing failures traced to this moly build up on the races. It is in fact an irregular build up of the moly and forms patches on the races and it had the same effect as dirt in the bearing.
So don't use moly or any moly additive on any ball or roller bearing application. This includes transmissions also.
On the other hand there are real benefits to using moly grease on our engines since most bearing are operating with 0.003 to 0.005 clearances and the moly will protect the bearing and shaft with a molecular coating of moly.
Lubriplate makes a moly grease used for construction machines and other types of exposed gears and bearings. It is a tacky grease that will not spray out of bearings or off of open gears. It is called No 3000 Heavy Duty Tacky Moly Grease,(part # l0108-098). A large tube costs about $ 3.50 and can be found at any bearing supply house or construction machine supplier. This grease is a black soft grease that is very sticky to itself and whatever it is on.

Now I'm back to plain old lithium grease. I've spent 1/4 of the price of a new bearing from Jerry and my palm is sore :oops: I haven't repacked yet, so if anyone cared enough to read and has a better idea pleas let me know and tell the guy at the parts store he should refund my money for the moly.

Brian
1983 P'up Diesel 4x4 long bed 4 speed w/ air 211500 miles

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puttputtinpup
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Re: Re-packing belt tensioner bearing grease suggestions?

Postby puttputtinpup » Fri Apr 09, 2010 3:12 pm

I thought Jerry recommended packing them with wheel bearing grease. Is that the same as moly?? and...go to Harbor Freight or Advance and buy a bearing packer gadget. I also hate packing bearings.
Last edited by puttputtinpup on Fri Apr 09, 2010 3:16 pm, edited 1 time in total.
Reason: typo

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wylie's pup
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Re: Re-packing belt tensioner bearing grease suggestions?

Postby wylie's pup » Fri Apr 09, 2010 6:44 pm

No moly is just one type of grease. If you read that article it talks about a model A club with a rash of rear axle failures. They claim it was from the way moly builds up on the surface. I'm far from an expert. You must be happy with your bearing packer. I've never use one. I can't count how many I sold the years I had a tool truck, but it was quite a few. I had a lot of guys tell me they didn't think it completely packed the bearing, so I never took one off the shelf. Guess I need to be the judge. Thanks for your input.
1983 P'up Diesel 4x4 long bed 4 speed w/ air 211500 miles

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pup daddy
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Re: Re-packing belt tensioner bearing grease suggestions?

Postby pup daddy » Sun Apr 18, 2010 2:32 pm

When I repacked mine I went to a feed and farm store and bought a syringe with the largest diameter needle they had, probably for cattle. I put the grease in it then slid the needle in between the rollers and injected. :D It still took a firm push but it think it is easier than using your palm and you can be sure you have grease all the way through the bearing.
1985 Pup diesel 4x4 4spd SB (daily truck)
1986 Pup diesel 4x2 turbo LB (Waiting for some love)
1990 chevrolet 454SS pickup
1983 Mercedes 300sd

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wylie's pup
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Re: Re-packing belt tensioner bearing grease suggestions?

Postby wylie's pup » Sun Apr 18, 2010 3:22 pm

pup daddy wrote:When I repacked mine I went to a feed and farm store and bought a syringe with the largest diameter needle they had, probably for cattle. I put the grease in it then slid the needle in between the rollers and injected. :D It still took a firm push but it think it is easier than using your palm and you can be sure you have grease all the way through the bearing.



THAT was a great idea.
1983 P'up Diesel 4x4 long bed 4 speed w/ air 211500 miles