Rear wheel bearing - "Knocking from suspension over bumps"

[JonB]

Yes.

On the right, the old shaft with inside bearing in situ, as it came out of the car. On the left, the new bearing and dust cover oriented per the old one - which seems to be like you said. The new dust cover looks correct. The old one appears thinner because of the rust, but on closer inspection of the picture, it seems to match the new one.

[alan.barker]

Yes, assemble as old.
Great stuff you're making nice progress.
Glad you understand, after living in France for 26 Years sometimes i don't know if i'm speaking French or English
Alan

[JonB]

Pas de probl?me, Monsieur...

Hmm, yes, great progress disposing of my money!

[rgh0]

Good luck Jon
Its not a repair approach I would have taken but it may work for a while if your lucky

cheers
Rohan

[JonB]

Well, it's time for an update.

The billet shaft arrived today, what a lovely bit of machining. It went straight into the freezer.

This evening, I took it to the garage along with the Loctite compound and bearings. Decided to remove the old compound from the carriers and put in new stuff. Getting the inner bearing onto the shaft was a total pig. I heated it up quite a bit, but it did not drop onto the shaft. In the end I had to drift it into place with quite a bit of effort, and the washer that keeps the inner seal in situ came loose. Can't see a way to fit the bearing even with a press that would avoid the seal retaining ring popping off. Anyway, I clipped it back on, and hope it stays put. Fitted the inner circlip.

Then to the carrier. Cleaned up the bearing seats and applied a little heat - to 40 degrees or so, very gently. Applied seating compound and lightly drifted the shaft and inner bearing into the carrier, then (with a bit of effort, because my circlip pliers are too small) fitted the big circlip. Then the outer bearing - fair amount of heat (to 80 degrees C or so), seating compound in the carrier, tap it in (much easier than the inner bearing) and in with the big outer circlip.

I've checked it all and there is no discernible play whatsoever so far. Perhaps I will feel some when the wheel is on (more leverage). I hope not. Anyway, the shaft rotates smoothly but stiffly because the bearings are new. There is no tightening of the bearings as I turn it (sure way to detect misalignment I reckon). Quick trial fit of the hub, seems OK, but will need a bit of heat and the proper torque to achieve a tight fit. Before then I will have to refit the halfshaft and brake disk, so I can put the handbrake on to stop it turning. I'll probably tighten it until the brake slips and then put the wheel on with the open ended spinner, drop it to the floor and re-torque.

Have to say, those bearings do not "drop on" even when the shaft is frozen and the bearings hot. The inner bearing was a swine as it has to go over the outer bearing's seating first. But it's done now, for good or ill, and I will leave it to allow the seating compound to cure before proceeding.

I'm still agonising about whether I should take the diff out to fit the new seals at this stage, but now I know how to remove the halfshafts (not to hard once you get the gist of it), I might leave it for another day. Would like to see if I cured the knocking with this expensive new shaft first.

[MarkDa]

I'd take the diff out it will be much easier to get at than working under the car.
Then you can tidy up the handbrake tree whilst nothing's in the way.
Which will lead to a handbrake refurb!!

[denicholls2]

The red stuff in the hub carrier is intended to prevent the groove problem from happening to the aluminum carrier. The root cause of fretting inside and outside of the bearing is that the bearing isn't a tight enough fit to the adjacent part and is able to spin in place instead of the bearing race and bearings doing the job. Over time, this causes fretting that turns down (or hones out) the adjacent part because the bearing races are the hardest metal in the picture.

Prevention is pretty easy, just use one of the weaker forms of Loctite to 'glue' the bearing in place as you see with the red leftovers. It shouldn't take much goop and then the bearings will spin on the races instead of the races occasionally spinning in place. If you overdo it, the next owner will hate you at bearing change time.

[JonB]

I'd take the diff out it will be much easier to get at than working under the car.
Then you can tidy up the handbrake tree whilst nothing's in the way.
Which will lead to a handbrake refurb!!

I'm already under the car - have not taken the body off yet!

Not sure what you mean by tidying the tree. The handbrake on my car works pretty well. PO had new pads put in. Only thing is the tree catches on the doughnut on the inner driver side if I forget to release it before driving off.

[alan.barker]

If it was me and i wanted to change the bearings and seals on the Diff Output shafts i would leave the Diff in place.
On the Diff Output shafts once the Circlip is removed the Diff Drive shafts can be removed with a sliding hammer no problem.
It depends if you want to take the risk of Frustacone center bolts seized in the Diff Ears or not.
You could be looking at another difficult job if you don't think twice
Alan

[JonB]

Alan

It's the seals only. There's no evidence of the output shaft seals going, just the pinion seal. So I may leave the output shafts as they are. On the other hand, if the diff is low on oil, there may not be enough for a leak to show. Or, fixing the pinion seal may show up weaknesses in the shaft seals. Or, the shaft seals, having run dry for [insert indeterminable time span here], may have deteriorated since the oil left the casing and will leak once I refill it.

As we all know, a Lotus maintenance plan usually goes to pot the minute one starts looking at the thing more closely. I am anticipating finding worn bearings everywhere after the fun I've had with the rear wheel. Sadly there is no evidence that the diff has ever had any attention in the paperwork.

[alan.barker]

Jon,
i would think it seems a good idea to top up the oil in the Diff.
To top up the Diff you will need to use a syringe or some owners have cut a hole from inside the boot. This makes topping up the Diff oil very easy . There are lots of posts about this handy mod and where to position the hole. It will make servicing easy in the future
Alan

[john.p.clegg]

....and give you access to the handbrake tree.

John

[JonB]

When the diff comes out, I will empty the old oil out (if any) and replace it.

I do wonder at that comment about a hole in the boot. Exactly what I have (I called it a drain hole) in my car, but I haven't checked to see what's below it yet. Probably not the breather as this is on the casing near one of the ears, in other words under the tank most likely. I should look!

Meanwhile, I had already acquired an oil pump bottle thingie with a hooked outlet pipe. One of these:

Draper transmission filler bottle / pump thingie

..so I think I should be able to fill it in situ. If I do this, I can see if the output shaft seals are leaking. But then I'll have to put the left shaft (doughnuts) on, and take it off again to do the pinion seal. Decisions, decisions..

[JonB]

....and give you access to the handbrake tree.

John

Not likely, the hole is the size of a 2p piece, and it's in the battery well on the floor.

Interested to know, what maintenance does the tree need?

[edit: Ah, now I see what you mean about accessing the tree! How come yours is behind the diff? Mine's to one side, and catches the driver side doughnut if engaged when driving.]

[alan.barker]

With the access hole you kill 2 birds with one stone. You can oil the Hand Brake pivot tree but the most important you can top up the Diff with the car level/horizontal on the ground. You need the car level so the excess oil in the Diff can run out the filling hole until it is the correct level. This can be done without crawling under the car and will only take 5 minutes. I think you need a break from crawling under in all the dirt and oil
Alan