Just finished installing new bearings and seals in the Avan hubs - they use the Ford style. Anyway I bought Japanese bearings with unknown seals...all went well till I went to replace the hub on the axle when I found I could not get the hub to full seat on the axle even by gently forcing it on using the axle nut. When it finally seated it was almost impossible to rotate the hub and I had to unscrew the nut 2 turns to spin easily. Seals were installed flush with the face of the hub by the way.
Realising this ain't right, I removed the hub and found the seal lip had been squashed between the seal shoulder and the inner race outer cup basically squashing it. I've done plenty of seals before and never had this problem. The neighbour reckons he never fully seats the seal flush to prevent this happening, but having never encountered this problem before I thought I ask what you blokes reckon.
Of course seals have to fit flush if you want bearings to last with out dirt or water ingress. It sounds to me that the incorrect seals were provided. If possible take inside and outside diameter measurements of axle and hubs. An example currently bearings used on many modern vans are Toyota Land Cruiser however the seals used are not Toyota but Two tonne trailer seals Maybe this is applicable to your situation. No matter when you get replacement seals slide them onto the axle to check the fit prior to installing in the hub. Cheers Allen
I have a Jayco with Ford bearings and the seal I use is ( GUEST 28600 ) Australian made ,I have never had any trouble with them,just make shore where the seal runs around the axle is clean and greased,buy the seals at any bearing place.
Thanks for the replies - Allen, I checked the seals on the axle before installing and they slid on nicely....outer shell was the correct size as it was a snug fit.
Lance C - , the old seal was a Guest brand 28600.
What was noticed was that the seal lip on the new seal was not the same as the old in-as-much as it was closer to the bearing than the old one - this could mean that the seal lip was flush up against the bearing cup (as installed) and when the hub was slid on the axle the seal lip could not 'flare' over the larger bit of the axle that the seal bears on. Anyway, I'll buy some new ones in the morning and not tap them fully home depending on what the brand is.
QUESTION - does the seal get tapped in till flush or till it cannot be tapped in anymore?
Thanks again fellas - bought the Guest 28600 seals and mentioned to the bloke at Bearing Service the problem I had - he reckons what happens is that some seals can catch on the shoulder of the axle where the seal sits when sliding the hub on and then get squashed between the inner bearing cone and the shoulder especially if the shoulder is sharp. He thinks it is not an uncommon problem which is normally not picked up by most people as they rarely if ever check their bearings. The old seal had certainly been squashed and torn as a result of this.
I tapped the new seals in flush as before and they certainly sat further from the bearing than the first lot (of unknown manufacture). Run beautifully.
Regards
When you buy new seals consider boat trailer seals.Over many years I have found them superior to the cheap JG 28600.Also seal the dust cap after adjusting the preload with a wipe of silicon gasket material.You will keep more dust and moisture out using this method,consequently bearings will last longer.
That's another bone of contention:....I thought I'd see what Google said and the first 2 sites said:
Site 1...... seat the bearings finger tight then with a spanner tighten another 1/4 turn.
Site 2...... tighten the bearing with a spanner till it resists rotation then back off 1/4 turn.
I use the 2nd method ....... I figure the 1st method may end up with the bearings too tight and have done so for the last 50 years and never had one fail.
tighten bearing nut firmly and spin the wheel both directions a few times. Back off the nut without moving the wheel hub on the axle. With something like a 12 inch shifter, put the shifter on the nut in the 1 o'clock position and let it drop. Will probably stop on the 4 to 5 o'clock position. Back off till closest split pin hole and pin it. When you wiggle the wheel across its face, should feel only the slightest to virtually no free play.
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Yes I am an agent of Satan, but my duties are largely ceremonial.
Great wisdom Troopy. Virtual to slightest free play is the way to go. What makes it difficult with most caravan axle stubs is that there is only one split pin hole.Years ago GM always had two holes drilled in the stub and from memory BMC did the same.Ford used an interesting little cap..don't recall its name..that fitted over the nut enabling a much finer adjustment.It's a pity they don't do it these days.
A very well respected engineer member of this and other fora once told me to use a tension wrench and tighten to 50 lbs/ft but do not turn the wheel, then back off the nut to the next available hole.
this works for my caravan which has now done some 40,000km with no issues.
frank
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Avagreatday.
Kathy and Frank currently at Home near Quirindi NSW
A very well respected engineer member of this and other fora once told me to use a tension wrench and tighten to 50 lbs/ft but do not turn the wheel, then back off the nut to the next available hole.
this works for my caravan which has now done some 40,000km with no issues.
frank
Although I don't doubt he has a reason for this, it does seem strange not to rotate the wheel to bed the bearing properly. Many OEM manuals for motor vehicles will tell you to rotate the wheel, and some will even have steps where it is done at a higher tension, back off and do it at a lower tension, then back off again and torque to a specific tension.
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Yes I am an agent of Satan, but my duties are largely ceremonial.
