classic motorcycle forum

I think things are going well... (and a lot faster now the weather is warming up!)

So - last night I got another couple of hours in the shed and....

Dribbled a bit of oil into the cylinder to help the initial ring seal and checking of compression


I got the engine spinning a bit by hand and then wiped most of the excess that had gathered at the top of the barrel.

Then it was time for some heat!


The last time I tried quenching copper it was some brake-line crush seals and I massively over-did it and turned them into slag....
So this time I played the heat over the gasket until I had a glow chasing the heat around the ring, then chucked it straight into the water


I only did one side, mainly because I really did NOT want to over-heat the thing and warp it out of shape, so, we'll see how it goes.  If it starts blowing very quickly... at least I now know how to get at it.

Shiny side up!


Buttoned up again.


I did try rotating the engine with my thumb stuck over the plug hole..... and there's definitely compression there!  Whether there's enough compression only time will tell....

So - time to assemble the rocker box:
All the bits:


First I cleaned up the threads for the rocker adjusters:


Stuck the cap-heads on the valve stems : (This is exactly the sort of thing I would forget if I hadn't put ALL the parts into little trays of associated parts, as seen above, I would highly recommend this practise if you're doing a job like this).


The exhaust rocker had a little bit of corrosion on it's shaft, (phnarr), so I gave the shaft a little polish (ooer!).  The inlet seemed fine.




Assembly of the rocker shaft with all their annoying little roller pins in situ:


I dribbled a little bit of oil into the roller-pin bearing assemblies to get them started, they definitely felt dry when I was first checking their movement.

As described earlier in the thread: the Rocker box assembly is done by pushing the bearing liner for the outboard (push-rod-side) as far out as it will go, fitting the top-cover of the box, then donig up tight ONLY the inboard screws, so the inboard bearling line is locked in place, and the outboard liner is "just" moveable ... then screwing the outer cover on, and the bosses on the inside of the outer cover then push the rocker arm into the box: pushing the outboard liner into the box just enough.  This means the rocker arm "end-play" is automatically controlled and is hopefully minimised.  I may actually re-do this process with a lot more photos next time I'm in the shed just to make sure I've done it right....

First thing to go on is the lower halves of the valve-covers.


I had to spend a bit of time trying to figure out where the washers on the bolts that hold the rocker box to the head (only 2 of em!) were supposed to go.  I didn't make an exact note of this when I disassembled the bike (d'oh!) but I think I worked it out eventually.  The complication is that there's also a bracket fitted above the rocker box that attaches to a head-steady which bolts to the bike's frame at the headstock, so I was trying to figure out if there should be a washer under the bracket, or 2 above....  I'm pretty sure there's no washer under the rocker box, it mates directly to the top of the head.

And that is where I ran out of time for the evening.  :roll:

I'm currently pondering the idea of trying to seal the valve gear with the 3Bond - it's not designed to be sealed (it's a shale-track engine, weeping oil all over the place is a design feature), so it's a problematic process at best.  Especially since I may well be placing and removing things repeatedly....

Food for thought over the weekend anyway.

NEXT TIME:  Rocker box fitting and TIMING! (well, hopefully!)

Nice going.
Probably an optical illusion, but is that piston circlip fully seated in it's groove all round?
I've been caught out before where the supplier fitted round section circlips in a square section piston groove, and they didn't seat well.

Could it be the ring (with a spring) that holds the headlight bulb in place?

Gulp.... here we go....

Time to start the assembly!

First I checked the locating of the crank oil feed quill, which, for some reason, my Dad had left out of the engine when it was last buil!  How the big end was getting oil I have no idea.....
I only ordered this recently, I had no idea it was supposed to be there until I spotted it on the Speedway Service list of parts and wondered what it was....  If I hadn't lost the little seal from the timing cover and had to order new ones I'd never have known about this part.



I also checked the crank-shaft oil feed line was clear:


Yup!


I then set up the timing side crankcase on a few blocks so that it would sit easily, cleaned up the remaining lithium grease which was on the thrust washers on the crank shafts, fitted the bearing cage and rollers on that side, and dropped it into the case:


Fitting the bearings was a lot of "fun" - they're soaked in R30 and have a tendency to try to pop out when you're pushing the next one into the slot: this little so-and-so made a bid for freedom and I lost 10 minutes hunting for the git, eventually I DID find it on the floor, I think it somehow ended up under my shoe!


Second set of bearings all in:



I then cleaned up the case mating surfaces with Sika Wonder Wipes,



Then again with meths on a clean bit of cloth.

Just a fraction of the blue paper and wipes I went through....


The Threebond was a lot more fluid than I was expecting, and I lost a bit of time hunting for a nozzle amongst my other tubes of goo - unfortunately couldn't find anything to fit so I had to just dispense from the tube.
I think this was a little too much - but there wasn't a "huge" amount of overflow on the outside of the cases.



Note that on this side of the cases (the Timing side), there's a "wall" or "lip" on the inside of the mating faces - this provides a locating key for the other side and a partial "labyrinth" seal, it also means that hopefully there's a lot less chance of the Threebond getting into the inside of the cases if you apply it to this side of the cases (as opposed to the other half), well - that's my hypothesis anyway...

I fitted the other side of the cases, used the small bolts to hold it together and align them, then fitted the workshop legs and cleaned up the small amount of excess 3Bond that oozed out.  (the Wonder Wipes were very good for that).

The next step was to fit the output side crank seal - this is a modification to the original engine, I'm guessing from F500 racing, and I really ought to try to find another one at some point.
I 3Bonded one side of the gasket (the cases side) and fitted the ally seal mount.
Interestingly, the 3 holes are NOT in exactly 1/3rd circumference locations, the screws wouldn't screw down until I rotated the mount 1/3rd.  If I remember I may etch an "up" arrow into the ally just to make it easier next time.


Test-fitting of the timing wheel - as I was looking at the cases on the legs, and the wheel hanging on the wall I had a sudden panic that it wouldn't fit!!
But it does.


It's a nice tight fit on the output shaft splines.  I also like implementation of the fine-adjustment collar.


Woodruff key, splines, output cog and fixing nut, There's also a couple of large washers that fit over the nut which stop the cog sliding off.



I rummaged around in the box-o-bits but couldn't find another nut of the right size and thread to temporarily hold the splines on the shaft: this nut is the right size, but wrong thread, but it'll do for now just to stop the splines falling off.


I need to make up a pointer for the timing wheel: current thinking is to just use a bit of wire-coat-hanger and one of the mounting studs to hold it in place, can't see any problems with doing that, so will do that when I get to that point.

Next job will be the barrel studs (copa-slipped, and with a touch of grease on the rotating bits), barrel, with 3Bonded paper base gasket, quench the head gasket : Ooo - a heaty bit, watch out for fireworks!, and the head, rocker box, then timing gear..... should be fun!

Now I am NOT going down the "Villiers Inustrial Engines" rabbit hole, but I will admit there is one! As Reg says in his memoir, P&R Williams were a big part of the Australian end of the business, in the 1930s, with a gap for the war, then 1946 into the early 1950s.

I suppose the 98cc Villiers Midget in the Ransome lawnmower is akin to the engine in the 98cc Waratah of the time? On second thoughts, don't answer that!

Leon