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I dont know if this applies to your pump or all pumps, but when Tom Papp rebuilt my pump he told me to grease my bearings until the lever got firm and no more unless you want a mess.
 

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In most cases you will more than likely find tha more often than not the main bearings are overgreased. I the mechanical contracting world and being involved in failure and predictive analysis, for every 1/2" of outside diameter of a single row (yours is probably double row) ball bearing, the capacity will be approx. 0.1 oz, so say its a 2.5" outside diameter double row bearing, a guess on the capacity would be 1.0 oz. if the bearing was new and unlubed.

Most garage type grease guns can pump 0.05 oz of grease per pump and you should add 1/10th of the origional grease load in the service interval, (jet pumps being annually), so an educated guess would be two pumps every year...

The reason for the 10% is oil runout (grease is normally in either a lithium base or soap to give it a thicker consistancy)....(no, really) and heat losses......

This is just a basic example, but it should be pretty close:)devil

GT :)hand
 

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Sit N' Spin
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Speaking of thrust bearings...

One thing that fails to be realized IMHO is that the thrust bearing is not only subjected to rotational force. There's literally hundreds of pound of pressure on the backside of the impeller that's literally trying to push the main shaft right through the bearing while it's rotating. For this reason, I'm a big fan of using extreme pressure grease on thrust bearings. I'm sure most pump builders would agree.
 

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Speaking of thrust bearings...

One thing that fails to be realized IMHO is that the thrust bearing is not only subjected to rotational force. There's literally hundreds of pound of pressure on the backside of the impeller that's literally trying to push the main shaft right through the bearing while it's rotating. For this reason, I'm a big fan of using extreme pressure grease on thrust bearings. I'm sure most pump builders would agree.
You have to be careful with extreme pressure grease as far as overgreasing and temperature, most extreme pressure greases are not designed for high bearing speeds..I prefer water resistant high temp myself, but i'm a little odd...:)sphss

GT :)hand
 

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In most cases you will more than likely find tha more often than not the main bearings are overgreased. I the mechanical contracting world and being involved in failure and predictive analysis, for every 1/2" of outside diameter of a single row (yours is probably double row) ball bearing, the capacity will be approx. 0.1 oz, so say its a 2.5" outside diameter double row bearing, a guess on the capacity would be 1.0 oz. if the bearing was new and unlubed.

Most garage type grease guns can pump 0.05 oz of grease per pump and you should add 1/10th of the origional grease load in the service interval, (jet pumps being annually), so an educated guess would be two pumps every year...

The reason for the 10% is oil runout (grease is normally in either a lithium base or soap to give it a thicker consistancy)....(no, really) and heat losses......

This is just a basic example, but it should be pretty close:)devil

GT :)hand
i just dont get it, please help??

you are saying two pumps total to fill the bearing??

my zerk is not plumbed directly into the thrust bearing. there is a cavity. the zerk is behind the bearing and the weep hole is in front of the bearing.

i was told to grease the thing till grease comes out the weep hole??
i am sure i have been steered wrong before but i know from doing it, it takes over 50 pumps to get it out the weephole.
so just knowing this makes me not want to believe that two pumps would even reach my bearing?????

please help??
just trying to learn??
 

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AKA OhOneWS6
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Discussion Starter · #8 ·
I think he is saying 2 pumps once a year to maintain the bearing.

By GT's math if a new "dry" bearing needs 1.0 oz and the gun is .05 oz per pump it would take 20 pumps to fill just the bearing. Then you would need to add the volume of grease needed to fill the path/cavity between the bearing and the zerk on top of that.
 

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I think he is saying 2 pumps once a year to maintain the bearing.

By GT's math if a new "dry" bearing needs 1.0 oz and the gun is .05 oz per pump it would take 20 pumps to fill just the bearing. Then you would need to add the volume of grease needed to fill the path/cavity between the bearing and the zerk on top of that.

Correct, the cavity in most situations should never be completely filled with grease, first off, when the grease gets warm it will thin and expand, then that shat will fling everywhere (really pisses the wife off too).

The two pumps is for an already in service bearing that has been previously packed with lube, the 10% is just a guidline we use on extreme duty motors and pillow block bearings, but the bearings are the same/similar, so it seems relivant.

On a normal situation, I literally use just enough grease at the end of the season to displace moisture.....

Sorry for the confusion.

GT :)hand
 

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Sit N' Spin
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On a Berkeley drive, I've always greased the bearing until I could just see grease start to run out the suction seal. Never had an issue.

Not sure how Jacuzzis differ from a Berkeley though.
 

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E-7 Sheepdog (ret)
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I think he is saying 2 pumps once a year to maintain the bearing.

By GT's math if a new "dry" bearing needs 1.0 oz and the gun is .05 oz per pump it would take 20 pumps to fill just the bearing. Then you would need to add the volume of grease needed to fill the path/cavity between the bearing and the zerk on top of that.
20 pumps is likely about right for a new bearing (only had that 2x in the last 20 years (1989 and 2004)) so memory is iffy.

My original manual said a few pumps every 10 hours, that's a lot more than I have ever given it (or dad did before me (31 years in the family)).
3 pumps 2 or 3x a year is probably plenty.

I buy whatever grease it is that DuaneHTP sells me, some red waterproof something that he reccomends. :p
Not a single bearing failure in 31 years.
Chewed an impeller to death in sand once, in one day. (1989)
Had an Al. one stress cracking behind 400HP and 5,000RPM once. (2004)

New bearing bought on overhaul, never had one fail.
 

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The correct grease to use is extreme pressure lithium grease
 

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Grease

On a Berkeley drive, I've always greased the bearing until I could just see grease start to run out the suction seal. Never had an issue.

Not sure how Jacuzzis differ from a Berkeley though.
We do pretty much the same thing except run a zip tie through the seal so it bleeds the air out so it's all just grease and no air
 
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