[Rattlebattle]

Having now split the cases and had a look I believe the t/s main bearing is suspect. There appears to be a small piece of webbing missing on the outside of the crankcase, against which the bearing abuts. This was not done by me, so either was there on assembly or it has broken off. It’s unlikely to affect the security or performance of the new bearing. I should get the revised one from Hitchcock’s tomorrow, together with most of the other gearbox needle roller bearings that I’m renewing anyway. The two inside the sleeve bearing have been extracted and will be renewed. They seemed to allow a lot of movement on the shaft. All the ball bearings are solid.
Having now extracted the main bearing I can see why it’s considered weak...I shall be really interested in comparing the original to the improved version. Mine appears to be an INA made in Slovakia. I would have thought that this would be ok. I wonder what the new one will be?

[ace.cafe]

INA is a well respected bearing company. However, there are plenty of counterfeit bearings on the market in India, and RE is famous for buying lowest price parts to keep costs low. It is possible that it could be an INA knock-off.

[Rattlebattle]

The ordered parts have now arrived. As far as I can tell the Hitchcock’s improved bearing is no different in design to the original, except that it is made in Belgium. It is a caged needle roller with an inner sleeve. I’ve just realised that what I thought was part of the t/s crankshaft is actually the inner sleeve of the main bearing. The sleeve is similar to the one on the drive side, except that it doesn’t slide off. Is this how it should be? How should I remove the t/s sleeve?

I have re-measured the conrod movement now that the crank is out of the engine:

No detectable up and down movement all round the big end. Sideways play, measured across the outer edge of the flywheels is most when in bdc position at a little under 1mm and less everywhere else. I guess this is normal because the ply will be magnified the further away the measurement is taken from the bearing itself. RE specify the tolerances but not where the measurement is taken. Assuming I can remove the sleeve, should I reuse the crank or play safe and buy another? Thoughts appreciated.

[ace.cafe]

That sleeve is the inner race for the bearing. It is not easy to get off.

My guidance will be based on what I have done with the pre-unit Bullets. I expect the procedure is the same.

First, have a look behind the existing race on the timing side crankshaft stub. There is probably a thin shim washer between the race and the flywheel. Check your parts book exploded diagram. That shim is the thrust washer. It might be damaged when removing the race. Might be a good idea to order a new one.

To remove the inner race, you have to use a lot of heat to expand the race enough to pull it off the crank stub. Since it will not be used again, we don't need to care about it. I use a propane torch with a directed nozzle to apply heat directly on the race, but not on the shaft. I put a cold wet rag on the crank stub to keep that as cool as possible. The race will need to be heated red hot with directed flame from the torch. Occasionally try tapping a steel wedge chisel into the gap between the race and the flywheel. You might also be able to use a large screwdriver or small pry bar. You need to get it to start moving away from the flywheel, and toward the end of the shaft. This is not easy. It takes a lot of heat(red hot) and prying, and could take time and effort. Eventually it will move away and you can pry/pull it the rest of the way off.
Then let it cool, and remove the thrust washer. Clean and inspect.

To put the new one on is similar.
Cool the crankshaft as much as you can. Put it in the freezer/fridge, or put a bag of ice on it, or something like that. Put the new thrust washer on. Position the crankshaft in a clamp or something to hold it so that the timing side stub shaft is sticking up vertically.
Heat the new bearing race in a pan on the stove and watch it closely. When you can just begin to detect the race turning a light golden straw color, remove it with tongs and slide it on the shaft immediately. I always keep a piece of steel or brass tube that can fit over the stub shaft and is longer than the stub shaft, to use as a drift to tap the hot race all the way down into place if it starts to cool and grab the shaft before it gets all the way into its place.
You must be quick about it. You have one shot at it, so make it count.
When it is in place, it will shrink-fit on the shaft right away and will not move after it cools.

That is how to do it. You need to have confidence about your method and your actions. I have done a lot of them, and it is always a pain in the ass, and a bit dicey because you don't want to mess up the new race. I have never wrecked a new one yet, but it is possible

Before you put the crank back into the engine cases, you must put it in some machinist's vee-blocks and use dial indicators to check the run-out on both sides crank stub shafts in case the crank got knocked out of true. It should be less than .002" total run-out, and even less is better. We can typically get them under .001" in most cases.

[Rattlebattle]

Thanks Ace; that’s clear enough. I’ll have a think about whether or not I should do it myself or let an engineer or mechanic do it.

[Rattlebattle]

Right; job done. In the end I took it to an engineer friend of mine who has the necessary kit, skill and experience to do the job. So, the t/s main bearing is installed in the case and the inner race on the crank. The gearbox shaft and sleeve gear blind needle roller bearings have been replaced and I am now in a position to proceed at leisure with putting the lot back together, having already fitted a decent Hitchcock exhaust valve and lightly ground in the valve seats. The big end bearing was pronounced sound by my friend, a conclusion I had pretty much made myself, with help from Ace.

We did discuss the hydraulic lifters, the outcome of which is that I'm going to fit new ones because I have a feeling that the inlet one is not lifting fully. One thing has us a bit puzzled: the Haynes manual (and IIRC) the RE one states that the lifters should be held upright when removed from the crankcase to avoid the oil leaking out. In this case how exactly is one supposed to fit new lifters (which I assume are unprimed) into the crankcase? Both manuals are silent on this. Do the lifters prime as the engine is turned over by hand before fitting the top-end (if so, why the big deal about not letting them drain down?) All helpful comments from those who know are welcome. Thanks.

[Haggis]

They self prime as soon as oil reaches them. Might be a bit tappety for a few seconds.
I have no idea why they mention keeping old lifters upright? As you say the new ones will have been all over the place.

[ace.cafe]

If you want to prime them, there are oil feed holes on the sides that you could squirt some oil into with a syringe .

I agree that they should self prime with the use of the electric starter.

[Rattlebattle]

Thanks guys, that's what I thought. No different to some ohc car engines that if left for a few days rattle on start-up and then quieten down once the oil gets up to the head. Maybe Haynes doesn't want owners to make an oily mess by storing the lifters on their side?
I always turn over an engine many times anyway when replacement parts have been fitted to ensure a good supply of oil from a cold start.

[Rattlebattle]

Just for information, I received the new lifters from Hitchcock's today. They have a plastic cap on the top and a little plastic plug in the hole in the side. It looks like they come ready primed.....Who knew?