Another trailer bearing question!!

[fisho_83]

Hi Guys,

Replaced my bearings a month or so ago, and I have done a fair amount of driving since then, they have probably done close to 1500km I would say.

I did a quick inspection of the seals at the ramp yesterday and noticed that the real seals have a small amount of grease formed around the edge of them. On one side the seal actually rotates with the hub whilst the other side does not. The seals still look in excellent condition and they are still well attached to the stainless ring/insert. The bearings never get submerged in the water when I reverse the trailer, and I top up the grease regularly. After a 45 minutes hwy drive yesterday the hub was not warm to touch at all.

Is this seal issue a normal occurrence, or is it going to lead to problems even though they never get submerged at the ramp? Do I need to look at replacing the seals again? :P

Cheers All
Fisho

[trymyluck]

Have you installed the seals correctly, as the seal should be fixed to the stub with a watertight seal and rotate against the stainless steel insert. If necessary use a sealant between the seal and the stub.

Mark

[Out-Station]

As per above. Seal should be tight on the axle and rotate in the housing, also depending on how they have machined your stub you can use an old seal cut to half its width to make a spacer and use this to keep the seal pushed up tight against the stainless housing as some axles let them drift back and hence let water in. If you need to stick/seal between the seal and the axle use Loctite 515 flexi flange sealant. Use this same stuff in the rim of the hub when you press your stainless housing in as dings/small scars here also let water in, I also use 515 on my bearing caps (i'm not a b buddy fan). I also stick 10ml of heavy gear oil in the hub. Works great, makes a slurry with the grease.

Cheer's, Scott

[fisho_83]

Thanks guys. Excuse my lack of mechanical knowledge, but I am still a little confused..........so I SHOULD NOT see the seal spinning when I rotate the wheel. I don't understand how it can be fixed to the stub but still rotate in the housing. Do you mean the housing should rotate against the stationary seal? Cheers again!!!!!

[trymyluck]

Yes the hub with the stainless steel insert should rotate against the seal where as with normal seals that press into the hub would rotate and seal on the stub.

[johncar]

Please don't think you are alone with this problem. Where I work I have to deal with this error every day and it would have to be one of the most misunderstood bearing seal installations.
with 2 piece marine seals the rubber part has to be locked to the axle and best to glue it on as previously said, the SS hub insert ring is to be carefully pressed in so that there are no leaks to the outer surface and then well lubricated with marine bearing grease on the inner surface and the SS ring now sealed to the hub rotates against the rubber part which must remain stationary and have positive pressure against the SS ring. If the rubber part ever rotates on the axle it is time to remove it and correct the problem, otherwise water may get in if submersing the axle. Correctly installed seals and dust caps, correctly packed hubs negate the need for bearing buddies for sure, but BB can still be used if preferred but don't over pump them, just enough to maintain some positive pressure to the hub. I have proved this with years of regular submersion with no water ingress at all and no BB's most of the time, you just need good seals and more importantly carefully installed.
New trailers more often have poorly installed 2 piece marine seals so it is often that owners become the victims of this shortcoming. Pretty sure I have had to fix every trailer I have ever owned and a waste of time even trying to explain to the manufacturer why they are installed wrong..

Pretty much repeating what has been said but just backing that up

[WalrusLike]

This is something I really want to learn for myself so I don't have to rely on dealers getting it right.

At the moment I think they are ok but it's taking three 'professionals' before it seems right.

I have seem a few utubes about it but they don't seem in enough detail or don't glue them on....

Another thing I gotta get around to... :)


(Using Tapatalk on iPhone so can't easily 'thank' or 'like')

[trymyluck]

Its really quite simple.
1. Pack and replace bearings in hub as per normal, I always replace both the cones and then pack the races with grease. Fit the inside race first and press the stainless steel insert in, this will hold the race in. Do not over pack the hub with grease.
2. Fit the seal to the stub. I always pack the outer part of the seal with grease. If the stub is in good condition then there should be no reason to glue in place but if you do then just ensure that the seal is sitting flush with the shoulder that the inner bearing seats against. You do not want the inner face of the seal contacting the face of the insert.
3. Install hub as per normal.

I have ran the same bearings for 3 years with no failure of the bearings or seals. I always stop and check the temperature of the hubs 30min to an hour into a trip and every time i stop afterwards just for peace of mind.

Mark

[johncar]

This is something I really want to learn for myself so I don't have to rely on dealers getting it right.

At the moment I think they are ok but it's taking three 'professionals' before it seems right.

I have seem a few utubes about it but they don't seem in enough detail or don't glue them on....

Another thing I gotta get around to... :)


(Using Tapatalk on iPhone so can't easily 'thank' or 'like')

Unfortunately it seems that many professionals also don't seem to know how these seals are designed to work and the first mistake they make is to grease the seal surface that slides onto the axle. That is the main error that installers make and will be the end of the seal and bearings in due course. If not glued it at least needs to be absolutely clean and dry as with the axle surface so that it is not inclined to spin on the axle.
I pretty much do the same as Mark above but I use the assembled hub to push the seal to it's final place with the axle nut just nipped up. If gluing which I usually do for added insurance I then don't rotate the hub much until the glue has set, perhaps just an initial gentle turn to make sure the seal has positioned correctly maintaining some light positive pressure on the outer external lip .
I am not sure how this goes with the inner seal contacting the SS ring but I have never had any issues but it might be more important if not gluing to maintain some minor clearance there to minimise any extra friction.
I then remove the hub and make sure everything is looking right and greased all up well but not too much. Filling the hub with grease will do nothing but cause problems. Take the axle nut up just firm until no play, then rotate a few turns checking for smoothness, if all ok then back off the axle nut to the next available slot and put the split pin through.
Important to get into the habit of always touching the back of your hand over the wheels near the studs at every opportunity and regular intervals while on your trip, as Mark said for that peace of mind and if anything starting to fall apart a warmer than normal wheel will give you warning.
These seals are excellent when installed well and I can't remember ever having a failure or any water in my hubs ever. However they are pretty useless if not done well and in that case you are possibly better off with the standard seals as they can be more fool proof, only problem being is that as the axle rusts it will chew the standard type seals out so they need to be replaced annually at least. This can be alleviated by using a small brush and maintaining a light layer of some good marine grease such as Triple Guard or the Yamaha product around the axle/seal external surface to slow down any rust forming or install SS speedy sleeves to the axle for the seals to run on.
You would think by now someone would have come up with a perfect and fool proof solution for boat trailers by now but as far as I can see they all need their own bit of care and attention to work reliably long term.

[Crunchy]

What type of glue should be used to fix the seal to the axle?