Trailer taper roller bearings

[Osprey]

Seen several posts in the past about correct way to adjust bearings.

My usual way is to tighten up until no play, then back off to point of no play but but wheel spins freely.

I found the 'official' way today ... while buying some new hubs.

Remove cap Remove split pin remove castellated nut & thrust washer remove stub axle & bearing assembly as complete unit (Rear bearing will usually stay on stub axle)

-change or clean up parts coat all with new grease ... waterproof if for boats. push bearing cones into the cups until fully seated (cones always point into centre of hub) push new grease seals into it's bore where required Slide hub onto stub axle Fit thrust washer and tighten castellated nut to 20Lbft Slacken off 1/4 turn

*** this now provides 1mm correct end float If in dobt over which castellation to put the pin, taper roller bearsings perform better slighjtly slack than tight. Insert new split pin & splay pack with grease, replace plastic cup

[Harry Bloomfield]

Osprey was thinking very hard :

1mm sounds rather a lot!

1mm at the hub will translate to much more at wheels outer edge. I tighten up to the point where it binds, then slacken off to the point where it no longer binds, no play is felt and then to the next point that the pin will fit.

[Dave Plowman (News)]

It does. On my car it says tighten to 5 ft.lb then back off one flat and insert split pin to nearest hole. 1mm end float would be an MOT failure.

[chris 159]

being a mechanic, i've always tightened until strong restriction is felt (to make sure theyre seated) then slacken until i can feel that the nut is no longer pushing against anything. so i'm guessing that would be about next to no free-play. i've never had a car fail an mot because of doing them that way anhd cant say that they worn prematurely.

Chris

[Osprey]

bearing hubs installation documents. It is also quoted the same in the Indespension trailer book .

As I said in my post I have always done it to no play ... but that is not what the book recommends.

[Osprey]

The comments are from trailer manufcaturer & trailer hubs Technical notes - and did not relate to cars.

[The Natural Philosopher]

Thats true..I once set up a 60's sports car 'by the book' and went back after a days hard driving and did it by 'feel'..the improvement in handling was more than perceptible.

[Guy King]

The message from The Natural Philosopher contains these words:

Several times I've set the timing on A-series engines by ear and feel rather than by the book. In most cases I suspect it was 'cos the fuel available now wasn't like the fuel available when they were made. Certainly get better driveability like that.

[Fred]

For tapered roller bearings - I would prefer to feel perceptible play. They are far more likely to fail if left with no play or overtight, though presumably on a trailer they don't get much use.

The high initial torque figure is to seat the bearings. Unless it was a very coarse thread I doubt 1/4 turn would give anything like 1mm of play.

[zikkimalambo]

I used to do mine by ear and feel. Once went to Wales, and a femal friend of my wife's who also went had been lent a Metro which was a couple of years newer than mine and sounded like an old dog (the Metro, not Vikki!). It had just been serviced by a main dealer who I suspect had used a strobe light or summat. I slackened off the pinch bolt and turned the dizzy by hand until it felt right, and tightened it up.

100% improvement!

[The Natural Philosopher]

Indeed. And then the weather got damp and cool, and you needed to do it all over again..