How to repack trailer bearings

dpmsgeek

Seaman Apprentice
Joined
Sep 4, 2016
Messages
31
Working on building out a youtube channel for fun. Here is a video of how to repack bearings by hand.
 

jimmbo

Supreme Mariner
Joined
May 24, 2004
Messages
13,639
Packing them is easy. Adjusting them is the difficult part
 

Silvertip

Supreme Mariner
Joined
Sep 22, 2003
Messages
28,771
I see two problems with this video. 1) The seals job is to stop grease leakage -- not to hold the bearing. When the bearing is installed, the shoulder on the spindle locates the bearing. 2) Tapered roller bearings need a little bit of slop. After the wheel is installed, grasp at the 12 and 6 o'clock positions and try rocking the wheel inward and outward. No movement the bearing is too tight.
 

frantically relaxing

Senior Chief Petty Officer
Joined
Nov 19, 2011
Messages
699
Adjusting is easy, and as Silvertip mentions, there must be some slop (aka free play). Why? Heat. If there's no free play when cold, there will REALLY be no free play when the bearings are heating up out on the highway. This is how the rollers start chipping away. And when one roller goes....

How to adjust? Simple. Run the castle nut on with your fingers. Wobble & roll the wheel while getting the nut finger tight. When it is, wobble & roll the wheel to verify it rolls smoothly, and there's no free play...

Now, back off the castle nut 1/4 turn and insert the cotter pin. Grab the wheel and pull back and forth. You should notice a little free play and a light 'thunk'. Perfect. Button up and go boating! :)
 

Silvertip

Supreme Mariner
Joined
Sep 22, 2003
Messages
28,771
With a new bearing install the pre-load technique is to wrench tighten (no breaker bars here) the bearing to help seat everything. Then back the nut off at least one turn. Then bring the nut back finger tight and check for play. If there is none, back the nut off one notch and recheck. Back off another notch until play is felt. Insert the cotter pin. Backing off one-quarter turn from finger tight may result in a bearing that is too loose. If play is felt between notches, turn the nut out (looser) to the next notch and install the cotter pin.
 

bruceb58

Supreme Mariner
Joined
Mar 5, 2006
Messages
30,584
To adjust the bearings, rotate the wheel while tightening the nut to around 20 ft lbs torque and rotate 10 to 20 revolutions to seat the bearing. Then loosen the nut and then finger tighten the nut. Align the whole of the cotter pin by loosenign(not tightening) the nut. It is very important to seat the bearing or the bearing will be to loose.

https://www.championtrailers.com/pre-loading-trailer-wheel-bearings/
 

Sweetwater17

Recruit
Joined
Jul 5, 2017
Messages
2
I have a question about the seal. When I was installing the seal I was using a bearing and seal driver. I got carried away and pressed the seal beyond flush. It bottomed out about 1/8" below the lip of the hub. Is this an issue or can the seal be pressed beyond flush with the hub? And can the seal interfere with the bearing or is there a lip preventing interference? I would think it is ok, but wanted to verify from folks much more experienced than me. Thanks!
 

Silvertip

Supreme Mariner
Joined
Sep 22, 2003
Messages
28,771
The seal goes flush. Pushing it in further has no benefit other than making it ride on a slightly different area on the spindle.
 

bruceb58

Supreme Mariner
Joined
Mar 5, 2006
Messages
30,584
Also if it's pushed in too far and hits the bearing, it's going to get damaged soon.
 

Sweetwater17

Recruit
Joined
Jul 5, 2017
Messages
2
Thanks for the reply. So it sounds like there is no risk to the seal being pushed in too far, as it will just sit at a different spot on the spindle. Thus, no need to remove it an replace with a new seal. Thanks again.
 
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