hub dust cap

995jim

Seaman Apprentice
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May 27, 2016
Messages
48
I need to replace my hub dust caps and want to go to the rubber plug center style for periodic inspections but wanted the audiences review of this style cap vs the standard solid cap with no rubber plug in the center. The current caps wont stay in place after i pulled them off for an inspection
thanks jim
 

Earl Cordova

Petty Officer 2nd Class
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Apr 21, 2021
Messages
160
Sounds like you need Bearing Buddies. The one with the rubber cap is for the style of axle that has a zerk fitting.
 

Chris1956

Supreme Mariner
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Mar 25, 2004
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The dust caps with the rubber inserts are also for the type of bearings that have zercs on them. In this case you pull the rubber cap and stick the grease gun onto the zerc, pump 'em up and then replace the rubber insert.
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
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Clean the hub and inside the dust cap with some solvent. When you push on, the little bit of grease inside the cap allows it to slip off


When you push on the cap, you sort of have to burp it. Then it will stay on
 

995jim

Seaman Apprentice
Joined
May 27, 2016
Messages
48
The dust caps with the rubber inserts are also for the type of bearings that have zercs on them. In this case you pull the rubber cap and stick the grease gun onto the zerc, pump 'em up and then replace the rubber insert.
so is this cap acceptable to use with a spindle that doesnt have a zerk?dust vap.jpg
 

Chris1956

Supreme Mariner
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Mar 25, 2004
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Gee, It doesn't look like it.
If the bearing assembly doesn't have a grease fitting, and the axle doesn't have one, you will want a Bearing Buddy type dust cap. The Bearing Buddy type dust caps have a spring loaded center with a grease fitting. The theory is that you pump them full of grease and the spring holds the center of the dust cap which puts pressured grease on the bearing.
 

Horigan

Senior Chief Petty Officer
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Jun 12, 2016
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726
That cap with the rubber insert will work fine. I run them on my trailer. I would still grease or seal the outer lip, like Scott suggests, so that interface seals well.
 

Chris1956

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Mar 25, 2004
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Rich, Running those hubs will work fine, as will the solid dust caps the OP had. However, I think the OP wanted hubs that would continuously grease the bearings. In that case it seems like he needs a bearing buddy-style dust cap.
 

airshot

Admiral
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Jul 22, 2008
Messages
6,099
Only tried the caps with a rubber center plug one time. They came with a used trailer. After filling with grease, the rubber inserts kept popping out when going down the road, allowing the grease to come out. Tossed them and went with bearing buddies. Never interested in trying them again.
 

995jim

Seaman Apprentice
Joined
May 27, 2016
Messages
48
Rich, Running those hubs will work fine, as will the solid dust caps the OP had. However, I think the OP wanted hubs that would continuously grease the bearings. In that case it seems like he needs a bearing buddy-style dust cap.
actually I had installed new solid zinc coated caps, popped them off for a periodic inspection and the next trip out I noticed 1 had come offand a 2nd was ready to fall off as well. So Im just determining the best way forward without losing more caps going down the road.
 

Chris1956

Supreme Mariner
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Mar 25, 2004
Messages
28,531
On trailers with brakes, heat from them can cause pressure inside the dust covers.

Of course, if no brakes, the bearings can be fully pumped up with grease.
 
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