FH - assembling the inner timing case

 Lots of work faces now, but an interim look at the cylinder head reveals that the valves and guides are beyond use - there is a couple of millimetres of rock at the edge of the valve head, with the valve half out of the guide. 

So, while I wait for a new set of guides, valves and springs let's start on the timing gear. Fitting the pinions is straightforward once I have deburred the Woodruff keys. The timing is set to the marks:

I've cleaned the dynamo straps since you have to have the inner timing case off to fit them. I'll plate these at some stage if I'm not too busy riding the bike:

The oil pressure release valve has been through the ultrasonic bath and has a new 5/16" ball. The old one was grooved and rusty:

Next, for the record, the pump drive washer is fitted:

I've made a small spacer from gasket paper for the end of the pump. Each of the stud threads has been cleaned up and fitted with blue Loctite thread lock:

I've used the original deep nuts - I've flattened these and recut the threads, adding a chamfer:

If you read my last post, you'll know that there is supposed to be a thrust washer in the nose of the pump, under the circlip. It needs to be 14.5 mm OD x 2 mm thick.

I had a bit of 3/4" EN11 in the lathe to make a late-pattern QD hub nut spanner, so I've used a bit to make the thrust washer:

I've left the pip in it to make it easier to get out. Next, the pump drive lock washer - the inner tang fits in a groove (like a keyway only less deep) in the end of the crankshaft. The tang on the new one is much wider than the remains of the one on the old washer  - time to get the needle files out:

With that in place, we can knock the tab washer down. On the crankshaft, I have bent the washer over both the lock nut and the pump drive sleeve:

For the record, the cam drive tab washer is knocked down too:

I've also finished polishing the timing cases:

I had to clean a lot of carbon off the timed breather sleeve before it would fit, and relieve a pip on the outside. It's fitted with the thickest cork washer available (5/32") and the gasket is coated with Wellseal. I've only done the inner face for the moment as I will want to take it off again.

Test fit:

That's it for now. Next I will probably fit the dynamo drive sprocket and it's seal, but then to do any more in here I need the dynamo and the Automatic Timing Device. Both of these bits need rebuilding.

More timing gear

In a recent post, we looked at stripping the gear in the inner timing cover. This time, we are going to complete the strip in that area in preparation to splitting the crankcases.

As you will remember, I'd removed the dynamo sprocket after a bit of a struggle and went on to make a gudgeon pin puller so that I could lock the crankshaft, prior to removing the rest of the timing gear.

I locked the crank with a bit of 5/8" bar through the little end eyes, protecting the crankcase mouth with some strips of 3/8" MDF, then I knocked back the tab washers on the oil pump & camshaft nuts.

Both these nuts appear to have a 25/32" hexagon, close to 20mm - I used a 20 mm six sided socket. Fortunately neither nut was particularly tight and they came off with no drama.

The camshaft pinion is provided with two 1/4" BSC tapped holes, so its easy to pull the pinion off:

With the cam pinion out of the way, I could wind off the oil pump drive and remove the oil pump. It's a mazak pump - we'll think about replacing that at some point, but it probably won't be in the first phase of this rebuild. I also took the opportunity to remove the oil pressure relief valve while the cases were still in the engine stand - it's all present and correct, but its full of gunge.

The oil pump drive is damaged - it's old damage, not by me fortunately. We'll have to get it clean to see if it is usable:

I was concerned about pulling the crankshaft pinion off - or rather, I was concerned about spending more time making another puller. In the event, it moved with the slightest encouragement from a pair of screwdrivers.

So that's it for the moment - I just have to clean the parts up, inspect and store them before moving on to the crankcase and crankshaft.

I'll just have a sort through all this sludge...

FH - inner timing cover

In the last instalment, we removed the outer timing cover to gain access to the dynamo drive, the ATD and the oil pump. We removed the dynamo drive chain but then stopped with this old, lightweight Japanese puller distorting itself while attempting to remove the large dynamo pulley on the idler pinion.

Over a week later, with three trips away for work I can tell you that the old puller never managed it and I had to make a new one. The new one, backed by a piece of 1" x 3/16" angle, is considerably stiffer though it loses out by having a coarse thread - the centre thread on a puller should be a fine, hard thread. Anyhow, it worked well enough and the dynamo pulley is now off.

Here we are - I told you it was off. Nothing untoward here apart from damage around the ATD which suggests it has been whirling around and rubbing the timing case:

The next step was to remove the inner case, which is held in place with four screws. A quick dose of the traditional remedy - leather hammer and impact driver, though not necessarily in that order, had it free in a jiffy. A mysterious 'tink' followed and this little chap appeared in the drip tray:

I wonder what it is?

Now we can see the crankcase, which looks fine & dandy. The idler will have to go back in to release the crankshaft & cam shaft nuts.

Here's the crankcase side of the inner timing cover. You can see the damage the loose ATD has caused in the top right of the picture.

And close up:

The magneto shaft, whilst it will turn the points, is very wobbly. This is more than a bearing problem - I think the shaft is broken.

Here's the timing cover in the parts washer, almost clean.

It was about now that I discovered you are not supposed to put paraffin (kerosene) in these little parts washers...