Primary Drive

The next step is to fit up the primary case for the second time. First off, make sure all the engine bolts behind the case are good and tight.

Then, a dose of Threebond on the flange between the two halves of the case, and bolt them up. This immediately reveals that we are missing three bolts - we have the nice stainless screw in the top, that came from Acme, but I have not sourced the others. So we can get on, one comes from stock - it's the right bolt, but the wrong material.



The clutch sprocket bearing cage goes in next, well greased and followed by the twelve needle rollers, courtesty of John Budgen:

Then the chainwheel goes on:

A quick spin reveals a horrible grinding noise... But I know what that is - I've forgotten the ring behind the chainwheel. Primary chain goes on, courtesy of Draganfly, with the clip safely fitted in the right direction:

I found that the primary chain is much easier to adjust if you flip up the rear mudguard - the access to the adjuster is much better.

So, all done. I need a few parts:

• bolts for the two halves of the rear case
• the bolt for the lower chainguard to the rear primary case
• a spacer for the rear case to the frame
• a split pin for the shock absorber
• spring washers for the clutch dome screws.

But that's it for the moment. Here it is, all together:



Finish off the Coupling Gear Case

Well, lets get on. Inspired by a post in the AOMCC forum, I am going to fill the coupling gear case with engine oil prior to startup. The coupling gear case is filled by oil draining from a shelf in the crankcase, through a small tube above the gears. This mean it fills using oil splashed from the big ends, so would naturally take a while to fill after starting. I placed this small pvc tube into the drain hole - it passes out of the engine throught the sump plate which is not fitted at the moment:

When the case is bolted up, i'll fill it with oil and then remove the tube. Before we proceed though, does the exhaust bracket bolt fit now or after the cover is on? Best test it. Is this the right bracket for this side? There are two different lengths: 

Next the crankshaft outrigger bearing, held in place with Loctite 603. This is the one that is supposed to be 1 thou smaller on the inner race ID.

Coupling gear cover, new gasket and Threebond:

And all in place. Amelia is now on a drip:

I must remember to fit the spilt pin in that shock absorber nut. One thing I may have to correct later is that the two studs fitted at the 9 o'clock and 3 o'clock positions, the ones that pass through the dowels, are really about 3/16" too short.

The head is just sitting on there - it is the old original one and is not staying...

A word of warning...

Original Amal handlebar grips smell a lot like dog toys...

 

 

Reciprocating Engine

At last we have a reciprocating engine again.

 

Yesterday, pistons prepped with tinplate/tiewrap compressors, block ready with new gasket stuck in place with Threebond.

It took 6 hours over two days to get to this point. I'd get the block over all the compression rings, and it would persistently get stuck on number 1. After five attempts, which included checking ring radial thickness again, I realized that the 2nd ring on No. 1 had no shiny filed surface on the end - it was straight out of the box and had not been gapped at all.

That's what comes from working sporadically over several weeks. You need military precision on your record keeping, and to meticulously check & recheck what you did yesterday...

Here we have it all bolted down, with Threebond oozing out & Clay Jones shiny stainless steel nuts holding it all together.

 

Magic.

Todays progress...

One pic today - and you'd have to have eagle eyes to spot what I have done!

Circlips fitted, small ends lubed up with engine oil, cams lubed ready for the block to go on.

I've also stripped the primary case off (& helicoiled a couple of holes), ordered the chains from Draganfly, cleaned out the battery carrier threads (which were full of paint), and tidied up the shed a bit.

Next stop, ring compressors. As it happens, 8-9 hours after writing the foregoing words this morning, I did do a bit more today. I finished my tin-strip ring compressors and did a trial fit of the barrel (well, it would have been THE fit of the barrel, had I not found that for some reason Number 1 piston will not slide gracefully into its cylinder, likes its brothers have done). The compressors work brilliantly though:

 

Base gasket in place ready for tomorrow:

Before I forget again...

This sprocket has 25 teeth. Standard solo is 24; 23 for sidecar:

 

This one has 44 teeth; you can get a 40 tooth version as well:

And this one has 19 teeth hidden under the chain. This is standard:

The rear brake drum should have 47 teeth.

Tomorrow I need to order the chains.

A monumental day

Pistons in, rings properly fitted!

Let's have a look...

A bit of spare time today, amidst fitting rings and general domestica. Time to drag Amelia out of her warm shed and have a look at her with the seat on:

One thing I have been a bit concerned about is the proximity of the rear tyre to the mudguard. You see a lot of these bikes with a huge gap here which looks wrong. Here's mine :

Looking good! 

Dynamo - recharged

Well here we are again, Christmas break and a bit more time. We've had Amelia for two years now, not long by Square Four restoration standards. Various diversions have come & gone, some are still here. I've had three months off work (diverted by a house renovation and a long hot summer, plus a daughter off to university), come back to a major project for Statoil, and I've been asked to write a book. A bike book!

But back to Amelia. Various thing are in the wings - we are working on the engine (long wait for piston rings; still not out of the woods)  sorting out the coil mounting, and finishing the dynamo. The dynamo is key because I understand that you cannot fit the end cover with the primary cases in place, and of course you need the dynamo to set up the valve timing, so I want to have it available before I finish the top end.

So, we had an old post on the dynamo, where we discovered it was intact electrically, but the bearings were shot and it was full of oil due to the failure of the oil seal. So the first job, which I did a few weeks ago, was to obtain the parts from Draganfly. After that, it was time to clear the bench and pull it apart again.

The bearing has to come out first:

Very easy with the heat gun and a large socket, though you have to bear on the inner race which is not ideal, but these are not a tight fit.

This is the drive end in pieces, with a replacement nut, oil seal and bearings from Draganfly. Those parts, looking like a shim and a gasket (because they are a shim and a gasket) are not original. They are (quite proficiently) home made and do not appear in the Lucas workshop instructions for the C35SD.

The bearing shoulder is very thin, and through in one place. So much for Lucas QC. Next stop, the commutator end - and as before the armature is a tight fit in the bearing. Lucas usefully provided a tapped hole, where you can use one of the long screws to push the armature out of the bearing:

So, commutator end in pieces. A proper clean ensues with white spirit to remove all the grease, plus wire brushes and wire wool to reveal a lovely plated surface on the body. Actually, there is no means of removing the commutator end bearing unless you have an expanding bearing extractor (which I don't), but luckily enough, with a bit of heat and some sharp taps on the vice, the old bearing dropped out.

New bearing in place:

Then, on to reassembly. Drive end in place with new bearing and seal:

Clean commutator (those deep scores won't do any harm) with its spring and thrust bearing. This is an early CS35D - later ones used on Mk2 SQ4s have a different arrangement here:

New brushes dropped in and springs hooked back over them:

Field coil reconnected to the terminal post:

And the end cap refitted with some grommets (plus a new O ring around the body, visible in the picture during brush fitting), new screws & fibre washers. By the way, this end cap is the original and was always black:

And here is the drive end:

Job done. I'll have to motor test it before it goes on, but I have a 1986 Ibanez PF400 to fix for my friend Simon.

Coil Mounting 2

Apologies for the time I've taken with this, but life (actually DIY) gets in the way sometimes.

 

This started life, as most of my fabricated parts do, as a piece of cardboard. It's cut from 16 swg cold rolled sheet, and will carry the coil vertically, mounted on the Lucas bracket in those two holes in the middle.

It mounts from the shouldered nut under the seat, and will fix to the gearbox top bolt.

 

 

 

Here it is again, after some redesign, with the bottom bracket tacked in place. I've tried to use 'styling' ideas from other Ariel components, to make it look as if it was designed in Birmingham in the 1940's:

 

And from behind. I will probably make those nuts captive, otherwise removing the coil will involve removing the bracket:

And various shots in situ. It now has a stiffened edge:

 

 

Looks tidy around the gearbox top bolt

 

 

Looks a little too close to the battery carrier. I will move that bottom bracket a little.

Painting next.

 

 

 

 



Fuel Tank

One thing (there may be others!) that has puzzled me is the absence of a crossover tube on Amelia's fuel tank. It seems to be a fairly well established fact that Solex-equipped Square Fours have one fuel tap, with built in reserve, on the left - because a tap on the right is in the way of the Bi-Starter knob and could drip fuel (they don't leak, do they?) on the distributor.

These first three pictures are all 1951 SQ4's, like Amelia:

Left hand tap (also note the brake lever stop! never seen one of those before) 

No right hand tap, no crossover loop. this bike has a drain point at the RH front of the tank, like mine

Obvious crossover loop

Amelia has two petrol taps, one drain point at the front, just like this 1952 KH

Left hand petrol tap, no crossover loop

Right hand petrol tap, no crossover loop

So... What do y'all think of that?