FH - back in action

 With the Square Four on the bench, the Huntmaster fixed and a trip for a job in Cromer in the offing it's time for a little bike ride. 

In preparation, I topped up the oil a couple of days ago as I had had the return system apart and expected the filter to be empty. I turned the engine over on the kickstarter with the plugs out in order to prove circulation before I used it again. 

After I'd finished my decorating job, I came back to the bike to find a little puddle under the rear chain case. I guessed there might be too much oil in the oil tank and so it proved: 

I filled the big syringe twice getting this back to an acceptable level. It's been off the road for a couple of weeks and obviously wet sumps! 

At the same time I adjusted the front brake and the head race bearings.

SQ4 - changing the oil

 It's high time Square Four had an oil and filter change, so with the oil return line repair complete on the Huntmaster the Square Four is back on the bench after a 10-minute run to warm the engine oil up. 

As usual it's an absolute pig to get the oil tank out but it's very easy to drain the tank and the sump - I have a new sump plate (well, it was new 10 years ago) with a drain bolt and magnet in the middle of it. I had something like 300 ml of oil out of the sump - I'm not sure whether that's unusual or not. 

I was surprised to find the sump strainer damaged - I think I'll get a new one from Draganfly. 

With the oil tank out I can degrease the area around the top of the box where the filler is - it's always quite mucky around here because it's very difficult to top the box up without getting grease everywhere.

The oil tank is also a very tight fit - it's always a struggle to get it out. I'm wondering if it's fouling the the frame tube, perhaps stuck between the frame tube and the gearbox plates.

I had the tank in the parts washer for 15 minutes washing the outside and the inside and was pleased to find very little sludge and no debris in the tank at all. There's obviously been some further washing of the engine through the detergent oil that I'm currently using as the cases appear very clean and the goo in the bottom of the tank and on the sump of drain plug is just like the dark grey substance you would get from the crankshaft sludge traps.

You can see one of the cams in this picture - the wear ridge is quite clear. I have a new camshaft ready to go in when I decide that I'm bored enough to rebuild the engine!

I filled in my maintenance spreadsheet but for the record the mileage is 4089 miles.

FH - chasing leaks

 This is the engine to oil filter pipe on leak test. No holes there!

However, this one is the oil filter to oil tank line:

So there's a nice leak there. The next step is to rework the oil line arrangement to the filter which I will do using a slightly different route between filter and tank since I think a contributing factor to this failure has been that the oil line has exceeded its minimum bend radius.

Charlie's Shed - chemical blacking

It's a fasteners that I've been making for the Model A are all turned from mild steel - there is no stainless on the bike at all. The plan is to use some gun blue or chemical blacking to reproduce the iron oxide finish from the original fasteners, called 'coslettising'. As an experiment I have used this product on the Huntmaster's oil filter bolt:

 Since I made it some years ago I have modified it to provide greater engagement of the thread. After turning I degreased it and suspended it in the cold blue for about 5 minutes followed by a rub over with linseed oil.

FH - finding weak spots

 Another local trip on the FH, and another 8 miles on the clock. Unfortunately it's perfect record is blemished by a puddle in the yard when we arrive home. This continues as long as the engine runs and stops eventually after we earth the magneto. Starting the engine again the next day shows the puddle begin again in earnest:

Poking about underneath suggests that this oil is coming from the engine to filter oil line which loops around the bottom of the gearbox. It looks very much like the hose has split, perhaps because the line is bent beyond its minimum bend radius. 

We'll have to remove the battery to improve access to this area and decide what to do. I used BSA A10 oil lines for both the return connections and I know that one of these was a little bit too long. I think what I'll do now is get some bespoke oil lines made up that fit properly.

Maybe I'll swap the FH and the Square Four around on the bench, clean the Square Four with the new sprayer and use that until the FH is fixed.

Incidentally, before the Square Four came off the bench I discovered that the oil filter was a bit looser than I would have liked. Perhaps that is responsible for some of the oily mess under the engine.

SQ4 - a bit of maintenance and a good clean

 Now that I've finished installing the electronic ignition and the FH is doing sterling service as the daily rider, it's time for the grubby old Mk1 to get some attention. Looking at the maintenance schedule shown here, there's a few bits that need attention not least an oil & filter change with a tank washout.

My U-Pol degreaser works wonders on the back wheel:

The next step is to lift the fuel tank and clean the cylinder head.

SQ4 - updating the ignition system

 The Square Four is on the bench at the moment for some maintenance and an electronic ignition conversion. 

I'm fitting an Accuspark system to see what advantages I can really gain. I'm led to believe that the bike will start more easily and will be smoother - I'm hoping that it may be slightly less rattly particularly in the coupling gears and I've also been told that running in town is better as the Hall effect sensor is less sensitive to the low voltage the dynamo provides at low speeds.

This is what you get in the kit - a new distributor base with the Hall effect sensor and 3 magnetic sleeves to go over the distributor cam. I understand that they are all the same magnetically but you use the one that fits best.

Here's the old setup - it works perfectly and is original. Starting is very easy so it will be interesting to see what I gain, if anything. I don't have to change anything permanently here: I can retrofit this system easily if I want to - I won't be cutting or removing any wires

There's two things to check in the battery box - one that it really is negative earth and two that I have removed the fuse to isolate the battery.

This is a useful view of the current cam and auto advance setup - you'll notice the odd springs. I don't think they're supposed to be like that but it's curious that I have a single spare spring in my box of ignition parts. Anyway, the second thing is that those rivets are raised compared to the body of the distributor and will foul the base plate of the new electronic ignition sensor so there is some work to do to provide clearance.

I've measured the diameter of the circle described by the rivets and marked it out on the base plate using a pair of odd-leg callipers, ready to cut a hole.

The base plate is actually quite thick - probably 2 mm or so. Since I can't find my Abrafile I have chain drilled inside the circle and will have to file it out. The housing is made from sheet steel set into thermosetting plastic and we don't want to crack it using some over-brutal method.

So that's it filed out quite neatly but we don't want to be too self-congratulatory at the moment do we! The problem is not obvious but actually it is not only the rivets in that ignition cam that are proud of the distributor body mounting face - that diamond shaped piece is also verging on being too high as well. I toyed with the idea of reducing the height of the whole cam assembly for a while but the real solution is to open the hole out again.

And as if by magic here it is, opened out to 40 mm. The difficulty that arises now is that the two M3 mounting holes for the sensor are very close to the edge of the hole and in one case the hole is no longer complete so I'll have to think of some other method.

The sensor was originally mounted on a little brass plate so what I've done is used that brass plate and the existing holes in the steel base plate to position a much larger brass plate that bridges the 40 mm hole in the base plate. I made the brass plate much too large but roughly the right shape and drilled for the two M3 holes for the sensor, fixing the brass plate into place on the base plate through the sensor holes. I then drilled two more holes outside of the large central 40 mm hole and fixed the new brass plate with two additional M3 screws. That way I could guarantee that the sensor would remain in its original position.

And here it is fitting nicely. The three rotating magnets are quite different shapes internally, and only one fits this cam - and it fits firmly.

And again we have the rotor arm in place and the distributor base plate screwed down.

I've temporarily wired it up for the moment - the red wire goes to the positive feed on the coil and the black wire goes to the contact breaker side of the coil. It will need some PVC tubing over the wires and some better quality eyelets, and I'm waiting for some thermal paste to use with the sensor and the brass plate but it will do for the purposes of testing. 

Hopefully I will get an opportunity in the next day or two to start the engine.

Post script: I started the engine on the 13th May, loosening off the distributor and retarding the timing to get it going; the Hall Effect sensor made an odd buzzing or fizzing sound which made me switch off in a hurry to check the wiring. The wiring was fine; the sensor wasn't tight enough on the baseplate which seemed to improve matters. It's still doing it and it sounds thermal. With the engine warm I advanced the timing to more or less where it had been before and went for a test ride. It's certainly smoother.

FH - over one hundred miles

Four days later and we are now over one hundred miles - there hasn't been any more smoke, and I have checked the points again which seem to be stable at 12 thou. I've backed the front brake off a notch and tightened up the back on the cable - they seem to be fine now, though the pedal is a little lower than I would like.

There's some oil mist on the drive side which appears as oil when the bike is on the sidestand - it drips from the head joint onto the primary case, though there are no other oil leaks. The head is going to have to be tightened down.

In other news, a mail to the splendid AOMCC gearbox man revealed that the kickstart was an after market one - it was harassing the back of my leg. In this picture, the one without the rubber fitted is the splendid new club one - you can see it is much less cranked:

It's a lot more comfortable when fitted.

As mentioned in the last post, I moved the gear lever up a notch only to find that it fouls the timing cover. The gearbox man confirmed it's the right one, so perhaps I well drop the footrest a bit lower to put my toe in the right place.

 Riding today I heard a groan from the drive side - getting home revealed the primary chain was too tight and the rear chain too loose - easily adjusted. I'm sure the steering head could do with a bit less clearance too, though the judder from a few days ago is now a barely perceptible click.

FH - another few miles

 Out and about on the Huntmaster again today shows that the steering head bearings are getting sorted. The handling is as good as ever, maybe a bit more sure on its feet and braking is very smooth - there is much less judder from the front forks - though it does need a little more adjustment. 

Yesterday I checked the contact points and found in both positions that there was a dragging fit on a 12 thou feeler gauge. The bike started readily as usual this morning and ran very well on a 4 mile trip to Cromer.

There is conspicuous oil in the drive side silencer however I didn't notice any smoke. Is this a temporary problem that comes from leaning the bike over and dripping oil into one of the valve guides? Certainly it happens after parking on the side stand and of course the side stand causes the bike to lean towards the drive side. The oil in the exhaust could have come from the various smoke experiences I've had over the last few days. Am I clutching at straws? Is it just the rings bedding in?

The handlebar mirror is a little bit loose and needs nipping up, and the centre stand needs some oil on the pivots. Oh, and before I go, the gear lever needs to come up a notch!

FH - steering head bearings

After the last trip, back in the workshop, a quick check revealed the expected loosened head bearings - wheeling the bike forwards and putting the brake on reveals a 'jolt' from the headstock which you can hear. To check them more physically, put the bike on the centre stand and put your thumb here in the dim & dark recesses of the top yoke, across the gap between the dust cover and the headstock:

With your other hand, grasp the front wheel and rock the bike backwards. This has the effect of pushing the steering column up through the headstock against the weight of the bike, and your thumb will be able to feel any movement. Don't vigorously rock it backwards & forwards - you don't want it rolling off the stand.

Mr. Waller suggests lifting the weight off the front wheel to perform this job, bit since the Square Four is on the bike lift I use the method described above.

So, having found some movement we need to sort out the problem. First slacken off the lock nut under the top yoke with your head race spanner; Clay at Acme Stainless has these, but you can also pick original ones up on eBay. 

This time, I had to loosen the handlebar clamp to get enough access to the stem nuts. Be very careful not to damage the paint on the tank - make sure the spanner fits well (so that the spanner doesn't slip) and that the tank is protected (for when the spanner slips):

Now, grasping the wheel again, roll the bike backwards against the centre stand whilst attempting to tighten the lower of the two nuts. You will find that the nut is now loose and can be tightened down - you will want to perform this feat of coordination two or three times.

When you are happy that the bearings are snug, and you can feel no more movement, tighten down the top nut. Move the handlebars and satisfy yourself that they are not binding anywhere. 

If you use your steering damper, reset it and you are good to go.

FH - more tinkering?

 Another little ride out today - twenty miles around the local countryside:

Starting easily, it's running a lot less busily with it's raised gearing.

The brakes are feeling much better now - there's quite a lot of travel but they are certainly biting.

The steering head bearings are very loose - there's a lot of juddering on braking. There might be an oil leak from the cylinder head area - there's a drip on the front of the top of the primary case, coming from the barrel, and there's some oil at the back of the barrel.

It seems to be quite smoky on the drive side - I'll keep an eye on this.

Everything else seems to be working well though I think I can hear the ignition hardening up again so perhaps those points are closing up.

All in all though - lovely!

FH - engine sprocket

 With Mrs H on the couch, asleep after a busy morning on the allotment I decided to do some shopping and on the way back get a bit of time in the workshop. After finishing measuring all the timing cover screws I decided it was time to change the engine sprocket.

Regular readers will know that I realised after riding the bike that the gearing was very low, and inspection of the pictures revealed that I had a 22 tooth engine sprocket: for solo use, I should have a 24 tooth engine sprocket. The Siamese pipe that came with the kit is another clue to the bike's history with a sidecar!

Pulling the primary case apart is a pretty straightforward exercise, if messy. I thought the case was empty of oil, assuming it had all been thrown out - in fact, the drain hole was blocked with red Hermetite and removing the plug had no effect - so it all ended up on the bench...

The primary chain has 74 pitches. A lot of adjustment of both chains had the gearbox in a suitable position for the new sprocket to go on. Note to self - for the future, using a socket and the slim plastic 3/8" ratchet drive on the primary chain adjuster makes it relatively quick to move the gearbox. 

Here it is in place:

I noticed that at some point in the dim and distant past the primary chain must have got very loose because the cast lug for the primary case screw right under the sprocket was very worn to the extent that oil would leak into the screw hole. I refitted the screw with a fibre washer. Incidentally, rather than use the large gasket with Wellseal I sealed the primary case with Threebond 1215 and no gasket.

These things are so easy to work on. I'd been considering whether to tackle this job before I rode the bike again thinking that I didn't want to have it off the road for too long but actually this kind of thing only takes a couple of hours. I hate to think how long it would take on a modern bike - but then you probably wouldn't have to do it in the first place! 

That's it all back together again a couple of days later:

FH - timing cover screws

 The Huntmaster timing cover has three different screw lengths which are not at all obvious - except for the short ones - if the screw holes are full of goo. 

I have cleaned out the screw holes with a twist drill and recut the threads with a long series 1/4" BSW tap so I know that they are in good shape. However the difference between the so-called medium length screws and the long screws is only 1/8" - so it's quite easy to get them wrong.

This afternoon, worried that a mix up of screws was leading to timing case leakage, I pulled them all out. I measured the depth of each of the holes with the vernier caliper and marked the relative depths on the timing case. I took this picture:

Now I have a good record of where the screws go. As it happens they were all in the right places.

FH - points

 Just for the record, I have used the on-board points spanner (with built in 12 thou feeler guage) to determine that the point gap for both cylinders is identical.

This means the ignition timing should be similar on both cylinders.

The lock nut for the fixed point needs a 8 mm spanner, which I've added to the toolkit.

FH - shaking down 3

 Well, the mild spitting and reluctant starting returned with a vengeance today. After the tank pinhole repair, the washer around the speedo cable and some general bolt tightening I fueled up and took the bike for a short commute of about 4 miles.

It was certainly reluctant to start, and was also lumpy as hell but it got me there and restarted when it was time to come home.

The journey back got progressively worse, and by the time I turned into town I had only one cylinder.

That cut out as I turned into the yard.

The engine sounded flat and 'hard' on the way out, just like the W/NG when it's retarded. The blue exhaust pipe in the picture screams 'retarded' too - the bike went straight on the ramp when I got home.

With the plugs out, I engaged top gear to use the back wheel to turn the engine with the magneto end cover off - the points had virtually closed up. Setting that back to 0.012" had the engine bursting into life at the merest tickle of the kickstart!

I greased the point cam, but I must check the gap on both cylinders.

Shame about the blue exhaust. That won't polish out but at least the tank isn't leaking!

FH - speedo cable

 After a suggestion from AOMCC member Stan, I've put an O ring around the speedo cable in an attempt to stem the drip of oil on the cable...

There's a fair bit of oil under the timing case, which might be coming from one or both joints or might be flowing down from the oil pressure regulator valve. There may have been no leak down the speedo cable, since oil can drip from the crankcase/timing cover onto the speedo cable...

FH - small repairs

 Spring is here and I'm away using the Square Four for some little house renovation jobs in a nearby town. There's a little bit of time in the workshop to do a few bits on the Huntmaster. 

We'll start with blocking that hole in the primary case that used to be used for the chain oiler before the fully Enclosed Rear Chain Case arrived. It's lost its blanking plug so I've made a new one up from a cheese head 3/16" BSW screw with a fibre washer:

The next one is a bit more serious. This is the pinhole in the fuel tank - I've taken the tank off for better access which is quite easy with these single centre bolt tanks. I've opened the hole up a little bit to clear the paint with a scriber and I've cleaned the area with acetone.

I've put a blob of Seal-All in that hole - just a tiny blob. After deliberating for a while over the approach I would take to this repair I realised that Seal-All had been sealing several holes in the W/NG tank for many years, and is still good. We'll see how this turns out tomorrow.

FH - shaking down 2

Well, I expected to do a few modifications or repairs after a bit of shakedown mileage - for example I now know that it needs a larger engine sprocket and I've got a couple of oil leaks - but I didn't expect to be taking it off the road quite so soon! I fully filled the tank for the first time yesterday having driven around with about a gallon sloshing about in the bottom for the last few miles and unfortunately it appears that the extra weight of fuel has revealed a pinhole. Now this tank has had a few weld repairs, it's been tested with air several times and filled with Slosh sealant - but there's still a pinhole.

You can just about see it here - there's a bit of a 'halo' around the hole. The tank is empty in this picture - with 4 gallons in there, it drips constantly.

Would something like Petro Patch work do we think? JB Weld perhaps?

In other news, fellow AOMCC member Stan has been in touch to tell me that BSA engine sprockets (A, B and M series) will fit and I have ordered one; I'll put a 3/16" BSW cheesehead screw in the open chain oiler hole in the outer primary case, because of course this hole is not used on FERC bikes and just provides a leak path. Stan suggested a couple of other things:

• Use Morris AG90 gear oil in the box
• Put an O ring under the speedo drive nut to stem the cable oil leaks
• It's worth getting an aluminium gear for your auto-advance unit as a backfire can strip the fibre teeth
• It's worth having a spare rocker shaft in your toolbox as these can break

You get great support in the AOMCC.

I did check where the idle screw had ended up after the hot adjustment yesterday - 1 1/2 turns out. However, starting today was a bit tricky - the bike was more reluctant to run. I had the choke fully on, perhaps the weather was too warm? It was spitting back a fair bit.

I've also ordered a new fuel cap.

FH - shaking down 1

 Well, I've decided that since in the last nine miles of circuits around the house the Huntmaster hasn't exploded, I have today filled it up and racked up another 15 miles.

Amongst other places, we've been to the lovely 1901 Weybourne Station on the North Norfolk Railway. Here the FH poses next to the 1960 - built English Electric Class 37, ready to depart on the last up-train of the day.

It's going very well. In the first nine miles I had adjusted the brakes 3-4 times, and after changing one of the levers they are starting to feel OK. 

Some days ago, I had adjusted the tickover. Today, having put perhaps 11 miles on the engine I stopped at Weybourne to find that it was less easy to start; adjusting it on arrival at home, I leaned it out 1/2 turn or more - the plugs are showing tickover was rich. I may have gone too far, but before I adjusted it the engine was very easy to start cold.

The other thing that is obviously wrong is the gearing - you can feel it is too low. Inspection of the build pictures show there's a 22 tooth engine sprocket fitted - standard fitment for solo bikes is 24, so we will have to see if we can get one of those.

Lastly, we have a timing cover oil leak and a primary case oil leak. I know that the old chain oiler screw hole is open, and there may well be too much oil in the primary case but since that will have to come apart to fit the new sprocket, we won't worry too much. The timing case is another matter.

FH - running in

 Another sunny day dawns and after more faffing about trying to get the chainsaw to run adequately I went out for some more circuits on the FH. Before I started though, I wanted to check the oil level and top it up - it was virtually full though, so perhaps it had wet sumped since it last ran and emptied the sump back into the tank in the couple of miles I did yesterday.

I also remembered to remove a large magnet I had used to stick a cable clip under the rear mudguard:

The bike ran beautifully, starting easily. The clutch seems a little notchy but the brakes certainly work, though the front is very spongy. There's a lot of flexibility in the lever which we will have to sort out.

It sat here happily burbling away while I took this picture:

On return, I went round the bike with the spanners. After my third circuit, I had noticed the front had started to clonk on braking and I was surprised to find the brake torque arm nut had loosened off.

This brings us to running in. This is what the Ariel instruction book has to say about running in:

It also tells you to change the oil at 1500 miles and decarbonise at 2000 miles. Pitman tells you to change the oil at 200, 500 and 1000 miles.

I'll be checking bolts, chains, cables and brake adjustment very frequently, especially at the beginning, but what of the head gasket? Shall I retorque at some point? I think not, at least not as a matter of priority since it has an annealed solid copper gasket.

The other thing that will be worth checking is the magnetic sump plug, to see if that picks up any nasty debris!