A Pocket Motorbike

[Last updated: Sunday, May 26, 2019.]

Found discarded by the roadside.

It's about 40 inches long overall. It's in rough condition, but it appears to be complete. All there is by way of ID are some decals on top of the fuel tank cowl.

'Silkolene' is a brand of motorcycle lubricating oils. 'Komine' is a Japanese maker of motorcycling gear. Googling 'iRC' gets me 'Internet Relay Chat', which looks quite irrelevant. Maybe the little bike was a trade show promotional item at one time. I'll probably never know.

It looks like the bike's owner may have lost interest in it at some point, and simply left it to sit outside. Compression feels good, so it's on with getting some covers off of the bike and checking for spark.

- - -

Fuel Tank Cowl And Seat

The fuel tank's filler cap has to come off. That was very tightly in place -- I had to knock one of the cap's wings CCW, using a piece of hardwood for a punch, to get it to unscrew.

At the very front, it looks like there used to be an M6 fastener, but the cowl has broken away there and the fastener is missing. I'll want to come up with an effective repair for that, so that fastening point can again be operative.

- - -

A 'Washer' For The Front Fastener -- SUNDAY, APRIL 28, 2019

Here's what I came up with so the cowl can have a front fastener again.

I sawed and ground that 'washer' out of 2mm thick steel flat. Getting the shape more-or-less right, and spotting the screw hole location were not easy. I'll paint that piece gloss black.

- - -

At the seat there are four Phillips recess fasteners.

'Got them out with the aid of an impact driver. They're M6 x 16mm truss head screws, No. 3 Phillips recess -- quite rusty. There are 18mm diameter flat washers under the screw heads.

And here's a view with the cowl removed.

There's still some 'fuel' in the tank. I'll get rid of that and thoroughly dry out the tank before attempting to fuel the machine. The tank's outlet tubing is horribly stiff; that'll have to be replaced.

- - -

Spark Plug

With the tank removed, there's access to the spark plug.

The spark plug is a JG BM6A, 3/4" A/F (across flats). Gap is a snug 0.025" The plug appears to be in pretty good condition.

And I have spark! And the kill switch up on the left side handlebar works. I'm on my way to a working pocket motor bike.

- - -

Sides Trim Pieces -- SUNDAY, APRIL 28, 2019

The blue grilles are each fastened by two M6 x 12mm truss head screws. Each screw location has a black vinyl washer between the frame and the grille.

The long plastic chromed pieces are each fastened by two M6 x 12mm truss head screws with thick black vinyl washers.

- - -

Main Cowl Assembly

The whole thing is attached to the frame at only two places, by two M6 x 20mm truss head screws, No. 3 Phillips recess, with Nyloc hex nuts, 10mm A/F. The screw and nut on the right side were seized with rust; I had to drill off the screw's head with a 5/16" cobalt drill.

- - -

Chain Guard

Fastened by two M6 x 12mm truss head screws with Nyloc hex nuts, 10mm A/F. Each screw location has a black vinyl washer between the frame and the guard.

- - -

Rear Fender

Fastened by four M6 x 16mm truss head screws with flat washers and Nyloc hex nuts, 10mm A/F. One screw and nut were seized with rust; I had to drill off the screw's head with a 5/16" cobalt drill.

- - -

Front Fender

Fastened by four M6 x 12mm truss head screws.

- - -

And that's all the covers off. Next up is to get at the carburetor to see what sort of state it's in. That means removing the engine -- carburetor service on this machine appears to be impossible with the engine in place.

- - -

Engine Removal

Kill Switch Wire

The kill switch lead has an in-line bullet connector for quick disconnection.

- - -

Exhaust Pipe/Muffler

At the engine -- two M6 x 16mm hex socket head cap screws with split lockwashers, 5mm hex recess. Mind the gasket.

At the rear (see the rear fender photo above) -- one M6 x 16mm hex socket head cap screw, 5mm hex recess, with a flat washer and a Nyloc hex nut, 10mm A/F.

- - -

Engine

Up top -- one M6 x 16mm hex socket head cap screw, 5mm hex recess, with a flat washer and a Nyloc hex nut, 10mm A/F. (The nut goes outboard.)

Underneath the engine platform -- four M6 x 16mm hex socket head cap screws, 5mm hex recess, with split lockwashers and flat washers.

Slip the chain off the engine's sprocket, and the engine can come out the right side of the frame with the throttle cable still connected. The throttle cable terminates at the engine in a cap with a 14mm hex on it. Unscrewing that cap releases what appears to be a throttle plunger, like so.

That's an arrangement that I've certainly never seen before. The design doesn't lend itself to bench-testing the engine.

And here's the engine up on the bench.

There's absolutely nothing on the engine by way of ID.

- - -

Carburetor Removal -- MONDAY, APRIL 29, 2019

Here's an underside view of the air cleaner and its clamp.

The hex on the clamp's worm is 7mm A/F. With the clamp off, I can see that the air cleaner is meant to screw onto a flange.

The female thread is a ruin, though, and the parts don't really mate properly.

Note that the choke is closed with its lever in the 'up' position.

The flange is fastened to the carburetor by two M4 x 10mm truss head screws, No. 2 Phillips recess. With the flange off, you have access to two 4mm hex recess cap screws.

- - -

Utter Defeat -- TUESDAY, APRIL 30, 2019

I dismantled, flushed and blew out the carburetor. With the carb reassembled and back on the engine, it's been no go. I haven't gotten a single 'pop' out of it, and I've tried pretty much everything.

This project is shelved until I find a way past this impasse.

- - -

'Got It To Start And Run -- WEDNESDAY, MAY 1, 2019

The engine has always exhibited what felt like very high compression -- it was difficult to get a long, quick pull on the starter cord. It dawned on me that that characteristic was abnormal, and was interfering with generating spark. (Although recoil starter cranks are short in duration, they're pretty fast. It takes something like 200 rpm to generate spark.)

I had nothing to lose, so I removed the one-piece cylinder to inspect the bore, and the piston and its rings. Nothing looked amiss, but when I went to get the piston back into its bore, the upper one of two piston rings snapped in two places. Here's a view of what's left of the piston ring.

I reassembled the engine with that piston ring omitted, and it started easily and readily. It idles, and accelerates with no load.

So there we are with a bizarre engine failure. The piston ring that broke must have been embrittled and stiff, and it was binding in the cylinder's bore. That's why the engine was so difficult and slow to crank, and so would not start.

- - -

Carrying On -- THURSDAY, MAY 2, 2019

So now I have a working, albeit lame, engine. I'll keep on keeping on. Perhaps a good engine will surface.

- - -

Right Side Foot Peg

It's upside down, its proper M5 fastening is missing; it's been pinned in place with a 1/8" x 1" roll pin.

I don't have a long enough M5 hex socket head cap screw for that, but I do have a suitable 10-32 screw.

I fabricated a 10-32 dowel-nut from 8mm diameter mild steel rod, and reinstalled the foot peg the right way around.

I retained the roll pin. That should work fine.

I don't like to mix inch and metric fasteners on a machine where it was meant to be all one or the other, but the cost and difficulty of always procuring just the right item are horrendous. At least I've done a neat job of it here.

- - -

Centrifugal Clutch

Four M6 x 20mm hex socket head cap screws (5mm hex recess) with split lockwashers fasten the clutch's output end to the engine.

And with that removed, the clutch's innards look fine.

Nothing there needs attention. I'll just button that back up and move on to the roller chain.

- - -

Roller Chain Drive

Here's the engine back in place with the chain installed.

That's a size of chain that I've never encountered before -- it's 1/4" pitch. The 'rollers' appear to be 1/8" long by 1/8" diameter. From what I can find of roller chain specs, that's a No. 25 chain.

The centrifugal clutch's output sprocket is 6 tooth. The rear wheel sprocket is 68 tooth, for a final drive ration of 1: 11 1/3. The chain has 142 links.

The chain was seriously rusty. A soak in solvent and an application of roller chain lube have got it to within reason, but there are still some seizure kinks to be worked out. There's plenty of chain tension adjustment latitude still available at the rear axle.

- - -

A Replacement Engine -- SUNDAY, MAY 12, 2019

My son came up with an engine.

I checked and it has spark, though it has no spark plug connector. Needless to say, that'll have to be rectified.

So, the original, lame engine can come out, and I can install and test this one.

- - -

A Shop-Made Spark Plug Connector -- MONDAY, MAY 13, 2019

The engine's ZBM6A spark plug has a screw-on M4 terminal nut, so I figured I could adapt a ring-terminal-style solder lug as a connector. Here's a view of what I came up with.

Perched on the cowl in the above photo is one of the solder lugs I used. Some electrical tape and shrink tubing made for a nicely strain-relieved termination. And by the way, here's a brief video that explains the various configurations of spark plug terminal.

- - -

An Engine Swap Failure

Right off the bat, I encountered a few snags:

• The throttle cable's threaded connection point at the carburetor was smaller than that on the original engine's carburetor. I had to swap carburetors in order to have a throttle cable connection. The carburetor gasket on the replacement engine didn't survive carburetor removal, so now I'm short a gasket -- I'll have to fabricate one eventually.
• The replacement engine's mounting screw locations weren't exactly the same as those on the original engine. Chain tension had to be slackened off a bit for the replacement engine to go in place.
• The two mounting screw locations at the clutch end of the replacement engine were shallower than those on the original engine, I had to add flat washers to the screws there so the screws wouldn't bottom out.
• The replacement engine's top mounting bracket is configured differently from the one on the original engine. I just left that unfastened.

I didn't bother trying to install the exhaust pipe/muffler, so I don't know whether there's still trouble to be encountered there. I connected the fuel tank and tried to start the engine. What I encountered surprised me -- exactly the same feeling of very high compression that I had gotten from the original engine before removing an embrittled piston ring. There was no starting the replacement engine; I couldn't get quick enough, long enough pulls on the starter cord.

So, on the face of it, it appears that the replacement engine may have a bad piston ring in it, just like the original engine had.

I took out the replacement engine, and put everything back like it had been. I'm back to having a working, but lame, engine.

- - -

Rear Wheel And Brake -- SUNDAY, MAY 19, 2019

I'd like to examine the rear wheel bearings, and dismantle and clean up the rear brake. 'Hope I'm not opening up a can of worms here.

Rear Axle And Wheel

There's an M10 hex nut at either end of the axle, 17mm A/F. The axle slips out, and two 15mm long sleeves fall away. (This is going to be some fun to get back together.) The wheel position (chain tension) adjusters are free to come away.

The wheel bearings are No. 6000Z -- 10mm bore x 26mm O.D. x 8mm wide. They don't strike me as particularly robust for the load they have to bear. There are no ID markings on the three-spoke wheel rim.

The tires are embossed, "XIANG LONG 110/50-6.5 TUBELESS FOR RACING PURPOSES ONLY NOT FOR HIGHWAY USE MAX PRESSURE 2.5 atm". That's something I've never seen before -- tire pressure stated in atmospheres. One atmosphere = 14.6959 psi, so 2.5 atmospheres = 36.73975 psi; call it 35 psi.

Brake Removal

• Cable end and return spring.
• Front stay fastener.
• Rear stay fastener.
• Lower stay fastener.

And that gets us to here.

And that's as far as I'll go. There's no pressing reason for me to dismantle the actual brake mechanism -- doing so might invite trouble. So, I'll put it all back together.

- - -

New Piston And Rings

After that go-round with the stiffened piston ring that broke and got deleted, my son got a replacement piston and rings from Ebay. Piston diameter is 44mm. The kit includes a wrist pin, wrist pin bearing and two retaining clips.

- - -

The new piston and rings are in. Compression is again quite high, but it's crankable, barely. I got it started, and it has run for a while without seizing up, so maybe I got it right.

- - -

'Beginning To Look Like Scrap Metal -- MONDAY, MAY 20, 2019

Today, it won't start at all, no how. Compression is so high that I can't get a decent long quick pull on the starter cord. I'm baffled.

- - -

'Got It To Start

I took the recoil starter off and applied a nut driver -- powered by a portable drill -- to the flywheel screw's hex head (10mm A/F). That got the engine to start. So I do still have an engine that can start and run. It's just that it has so much compression, I can't operate the recoil starter to good effect.

Recoil Starter Failed

The plastic recoil starter packed it in. The hooked outer end of the torsion spring straightened out and left its retainer. There's no fixing it. I salvaged the cord and handle and junked the rest of it, except for a coil spring that may be useful some day. I installed the starter from my spare engine.

Back To Where I Was

Since the engine with a new piston and rings is unstartable, I decided to go back to the old piston with one ring. With that done, compression is within reason and I can start the engine.

'New' Recoil Starter Cord Failed

The cord's jacket kind of unravelled. I replaced the cord with the salvaged cord from the old starter.

- - -

So, I'm back to a working engine with only one piston ring. If nothing else, this motorbike is a bottomless make-work project.

- - -

Front Fork Time -- WEDNESDAY, MAY 22, 2019

I'd rather not have to do it, but the front fork and handlebars look so bad that they just have to be refinished.

Let the dismantling begin.

Twist-Grip Throttle Control Handle

Loosen off two 4mm hex recess screws, and the handle can be twisted off. The handlebar underneath has been wrapped with tape.

I guess the handle's inside diameter was a little oversize for the handlebar, so that's how the factory 'fixed' the problem. Handlebar length for the throttle control handle beyond the brake lever clamp is 4 23/32".

Front Brake Bracket

Two M6 x 35mm hex socket head screws, 5mm hex recess, with Nyloc hex nuts, 10mm A/F.

Front Brake Lever

Loosen off one No. 2 Phillips recess clamp screw. I had to peel off the tape pn the handlebar to get the brake lever to come off easily.

Left Side Handlebar Grip

It has to be thoroughly warmed with a heat gun to soften it so it can be coaxed off.

Rear Brake Lever

Loosen off one No. 2 Phillips recess clamp screw.

Front Wheel

At the left (brake) side, there's a 17mm A/F Nyloc hex nut and a flat washer. At the right side there's just a Nyloc hex nut. The 10mm diameter axle can be slipped out once either of the two nuts is off.

There are two sleeves between the wheel and the fork. At the right side, the sleeve is 5.5mm long. At the left side, the sleeve is 8.25mm long.

Marking 'L' And 'R'

Now is a good time to mark the fork tubes and handlebars 'L' and 'R' with an engraving tool.

Fork Tube Top End Caps

They're chromed plastic caps that just pry out easily. Note the position of the tops of the fork tubes, just below flush with the tops of the stays.

Kill Switch

Loosen off one No. 1 Phillips from underneath. Disconnect the switch at its bullet connector.

Handlebars And Fork Tubes

Loosen off the various clamps with 4mm and 5mm hex keys. Things are balky from rust, but the pieces do come apart.

- - -

Done And All Back Together -- SUNDAY, MAY 26, 2019

I took it for a little spin, and the left side foot peg broke.

The steel foot peg stud only extends part way through the peg, so the peg snapped off right at the end of the stud. The more I see of this motorbike, the less favourably impressed I am by its engineering and construction.

I had a salvaged M12 x 84mm bolt, so I bored 12mm diameter through the entire length of the peg. That gave me a fully reinforced foot peg.

I'll put it up on Kijiji and see if I can unload the thing.

- - -

Update -- FRIDAY, OCTOBER 11, 2019

I never did manage to sell the thing. I've given up and withdrawn the Kijiji ad.

I tried starting it again a couple of days ago, and the starter's recoil spring broke, so there's an end to the project.

From what I've seen of pocket motorbikes, the things are junk. I'm unlikely to ever see another one, but in the event that I do, I'll be inclined to stay well clear of it.

- - -

To be continued.

# # #

FEEDBACK

# # #

A Sears Craftsman 5/23 Trac-Drive Snowblower

[Last updated: Thursday, April 25, 2019.]

The "5/23" indicates 5 hp/23 inch swath. Model number is C950-52672. Serial number is 370984 68. It was made in Canada, so it must be a real old-timer.

The engine starts and runs reasonably well, and the transmission works. The machine won't freewheel satisfactorily at all; it sort-of freewheels if you drag it from the front.

There's a foot pedal affair at the rear of the carriage that mystifies me. With the foot pedal in its up position, the whole frame of the machine can be tipped up in front from the rear of the carriage. Pressing the foot pedal down locks the frame to the carriage. I think that feature may have something to do with freewheeling.

Googling for a user's manual has turned up nothing; the model seems to scarcely exist online, so I'm really on my own here.

Like any old piece of equipment, the machine is due for some TLC throughout, but the absence of easy freewheeling is especially troubling. I'll concentrate on getting that sorted out first, so I'll get the engine off, and the auger housing separated from the frame. That should leave me with a manageable unit that I can unravel the mysteries of. I really must resolve the freewheeling issue to make the machine nicely useable.

- - -

Discharge Direction Crank Removal -- TUESDAY, APRIL 16, 2019

At the front end, a cotter pin and washer.

And up at the handlebar, a 3/8"-16 eyebolt's nut and washers. (9/16" wrenches needed.)

Discharge Chute Removal

Three 5/16" x 3/4" carriage bolts with 5/16" SAE flat washers, split lockwashers and 1/2" A/F hex nuts.

V-Belt Drives Cover Removal

Two 1/4"-20 x 1/2" hex washerhead screws, 3/8" A/F, with 1/4" SAE flat washers. With the cover off, the V-belt drives are revealed.

The 1/2" wide belt at the left in the above photo is auger drive. The 3/8" wide belt to the right is locomotion drive.

The auger drive belt's tension idler is operated by the right side lever on the handlebar. The locomotion drive belt's tension idler is always operational; a spring keeps it in the belt-tensioned position.

Now is a good time to carefully check pulley alignment. If anything is off, determine what measure(s) will have to be taken to correct the problem. If all is correct, note/sketch how idlers are assembled; check for asymmetrical idler hubs, and the presence of washers. At the auger drive pulley, note the position of the fastening in the tension arm's adjustment slot.

- - -

Engine Removal

Four 5/16"-18 x 1 1/4" hex head screws, 1/2" A/F, with split lockwashers. Tip the engine up from the rear to slacken off the V-belts, and slip the V-belts off their engine pulleys. With the engine away, the locomotion V-belt is free to come out. The belt measures 31 3/4" outer circumference (O.C.).

- - -

Unit Upended

With the engine off, it's fairly easy to tip the machine up onto the face of the auger housing.

I've decided to leave the auger housing attached to the transmission frame for now. It looks like it'll be a lot easier to deal with the Trac-Drive's troubles with the machine standing up like this.

- - -

An Obvious Flaw

The left side pivot screw for the foot pedal is missing.

Whether that has any bearing on my freewheeling problem, I don't know, but I doubt it. In any event, that flaw must be corrected. It looks to me like a special shoulder screw was there originally. I'll have to fabricate something for a replacement.

- - -

Bottom Cover Off

Nothing looks amiss inside the transmission. It looks just about like any other snowblower transmission. The Trac-Drive is incredibly stiff, though. I suspect that much of the engine's power has been eaten up just to make the Trac-Drive operate.

I'll get after that missing foot pedal pivot. Once I've got that corrected, I can pursue dismantling the Trac-Drive.

- - -

Missing Pivot Screw Re-Created -- WEDNESDAY, APRIL 17, 2019

At the left in the above photo is my new pivot screw, made from an ordinary 5/16"-18 hex head screw and hexnut. The head is undersize at 1/2" A/F, but it's still adequate for the installation. (The hex head on the original screw at the right is 5/8" A/F.)

The shoulder bushing is 7/16" diameter x 17/64" long, exactly matching the shoulder dimensions of the original. The screw's head has been turned down to a height of 9/64", matching the height of the original screw's head. I've attached the shoulder bushing with red threadlocker.

- - -

Pivot Screw Installed

Note the Nyloc nut. Originally, there would have been an ordinary hex nut and a split lockwasher. That's where the designer went wrong.

The forcefully spring-loaded foot pedal crank exerts considerable torque on the shoulder of the pivot screw whenever the foot pedal is operated -- enough that a split lockwasher wasn't up to the task of keeping a nut from loosening. Once loosened enough, the nut 'walked' away, and the nut, lockwasher and original pivot screw went missing. A Nyloc nut should stay put, even with a slight bit of loosening. A prevailing torque nut might be better yet, but I don't have any of those.

Note also the wire loop. That's there to restrain the end of the spring from creeping leftward. A pushnut was there originally to serve that function, but that's been lost as well.

- - -

Trac-Drive Outer Plate Removal

• Two 1/4"-20 x 1/2" hex washerhead screws, 3/8" A/F.
• At the front, a 5/16"-24 x 1/2" hex head screw, 1/2" A/F with a flat washer and a ring washer.
• At the rear, a 5/16"-24 x 1/2" hex head screw, 1/2" A/F with a flat washer and a track-tensioning eccentric.

And that gets us to here.

And now I can see why this snowblower won't freewheel -- the rear idler wheel is seized on its axle. The whole Trac-Drive assembly is going to have to come apart, and that's going to be challenging.

- - -

'Got The Rear Idler Wheel Out

That wasn't too difficult after all. I undid the axle screw on the inboard side, and that permitted the wheel enough freedom that it could be removed from the track. The track is now free to come off as well.

What we have here is sketchy design. The plastic wheels turn on steel axles with no provision whatsoever for lubrication. When new, the low-friction plastic-hub/steel-axle interface worked nicely. With age the steel axles oxidize and the hubs bind. The outcome is a snowblower that won't freewheel.

Anyway, I should now be able to hammer the axle out of the idler wheel, and get that all freed up. I'll give the front cog wheel and the chain drive plenty of roller chain lubricant, then repeat on the other side of the machine.

- - -

Axle On Its Way Out

Hammering didn't budge it. I got it that far with the hydraulic shop press. I should be able to knock it the rest of the way out with a hammer and a punch.

The axle is very badly corroded; it's little wonder that the snowblower wouldn't freewheel. The idler wheel on the other side is not as bad, but it's stiff.

- - -

Left Side Trac-Drive Back Together

And it's freewheeling nicely. As it turned out, the front axle was in pretty bad condition as well. I wire brushed both axles on a wire wheel machine, and reinstalled them with Molyslip grease for a lubricant. That should keep things in good order for a long time. So it's on to the right side Trac-Drive, which appears to be in less bad a condition.

- - -

Both Trac-Drives Reassembled And Installed -- THURSDAY, APRIL 18, 2019

The machine now freewheels, and can be pushed and pulled about, albeit with effort. Tracks inherently offer more more rolling resistance than do wheels, and this snowblower will never move as easily as a wheeled snowblower will. That's the price to be paid for the superior traction provided by the Trac-Drive.

Scraper Bar And Skids

All fasteners are 5/16" x 3/4" carriage bolts with 5/16" SAE flat washers, split lockwashers and 1/2" A/F hex nuts.

The scraper bar seemed too low for the auger height that I wanted, so I reversed it to get it up higher. I set the skids for lowest possible auger height. I now have scraper bar clearance of about 1/8", with auger clearance of about 1/4". That should be ok for smooth pavement. A gravel driveway would call for greater clearances.

Separating The Auger Housing From The Frame

(The green twist-tie in the photo below is there to keep the locomotion V-belt tension idler's spring taut. The bottom end of that spring tends to leave its anchoring notch in the frame if the spring is allowed to go slack.)

The auger housing is fastened to the frame by four 5/16"-18 x 1/2" hex washerhead screws, 1/2" A/F. The two lower screws need to be loosened off, not removed. The screws are very awkward to get at. You may want to stand the machine up on the face of the auger housing to gain access to them. Then.,with the machine level as for normal use, remove the two upper screws.  Tip the frame up and the two lower screws will act as hinge pins. That gets you to here.

The auger drive V-belt can be removed, and the condition of the impeller bearing can be checked. Auger drive V-belt outer circumference (O.C.) is 30 1/4". The impeller bearing on this machine feels ok. I suspect that the bearing has been replaced at one time because the set screws in the auger drive pulley are not the original 5/16"-18 square heads; they're 3/8"-16 hex heads.

When re-mating the assemblies, clamp the auger clutch lever to the handlebar with a suitable spring clamp. That'll keep the auger drive brake shoe out of the way of the auger drive pulley.

Locomotion And Auger Drive V-Belt Tension Idler Pulleys

The two idler pulleys are identical. The fastenings are 3/8"-16; two 9/16" wrenches are needed to remove them. Note the orientation of the pulleys' asymmetrical hubs, and the placement of flat washers. At the auger drive pulley, note the position of the fastening in the tension arm's adjustment slot. The thin hex nuts are prevailing torque types.

The pulleys' bearings are integral with the sheaves. The bearings have seals, but roller chain lubricant can be applied so it will wick into older bearings to extend their life.

- - -

Engine -- FRIDAY, APRIL 19, 2019

It's a 5 hp Tecumseh Snow King. There's supposed to be a Sears engine model number on the cowl somewhere, but I can find no trace of one. There are several things I want to attend to:

• Carburetor dismantled and cleaned.
• Fuel delivery tubing redone.
• Cowl and flywheel off -- ignition system inspected.

Carburetor Cover Removal

• Choke knob pulled off.
• Keyed kill switch wire disconnected -- one No. 8 x 3/8" pan head threading screw in a bracket below the carburetor cover, No. 2 Phillips recess.
• At the top, right by the muffler -- one 10-24 x 3/8" hex washerhead screw with external tooth lockwasher, 5/16" A/F.
• At the left side -- two 8-32 x 5/16" pan head screws with captive external tooth lockwashers, No. 2 Phillips recess. (One of the two screws is missing on this engine.)

And removing the cover reveals that the keyed kill switch has come apart.

A ty-wrap may fix that.

The governor link has a peculiar kink in it.

That arrangement looks very sketchy. The throttle can't open fully; the governed speed controller's speed adjustment screw is at maximum. The governor linkage has obviously been tinkered with, no doubt to ill effect. To be attended to in due course.

- - -

Spark Plug

It's a Champion RJ19LM. Gap is 0.030". The spark plug looks fine -- nearly new.

- - -

Cowl Removal -- Governed Speed Controller

[Note -- SUNDAY, APRIL 21, 2019: The following bit about the governed speed controller is in error. It turned out that the governed speed controller is not attached to the cowl.]

This looks dreadful.

The governed speed controller appears to be riveted to the cowl. There's no provision for disconnecting the kill switch, short of dismounting the kill switch contact itself, which I'd rather not have to do.

I think I'll install a quick-disconnect right now, and have that aspect of the machine corrected for good.

- - -

And here we are with a 3/16" in-line spade terminal arrangement.

So that's taken care of. The kill switch can be disconnected, and the governor spring unhooked to begin the process of removing the cowl.

At the kill switch terminal bracket, there's a 1/4"-28 x 7/16" hex head screw with captive external tooth lockwasher.

At the carburetor, disconnect the primer tube from its nipple.

Cowl Removal -- Electric Starter Drive Entry Point Cover

This engine can accept an electric starter motor. When such is not installed, there's a cover for the area where the electric starter's drive would enter the cowl.

High up is a No. 8 x 3/8" pan head threading screw, No. 2 Phillips recess. That screw is awkward to get at; an offset screwdriver is called for. Lower down there's a 1/4"-20 x 1/2" hex head screw with captive external tooth lockwasher and 1/4" SAE flat washer, 7/16" A/F. That screw is also a cowl fastener.

Cowl Removal -- Upper Fasteners

This looks peculiar to me.

Surely none of those three screws associated with the top of the cowl can be cylinder head screws. Let's see. The screws' hexes are 1/2" A/F.

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I got the centre screw out, and it appears to be a cylinder head screw. The remaining two screws are very tight, and I can't get enough purchase on the engine with the engine off the frame on a work surface. I'll have to reinstall the engine on the snowblower's frame.

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Two Out Of Three Out

'Got the engine reinstalled on the frame and the leftmost screw out without breaking it. Here goes for the remaining screw.

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And that's three for three. The screws are hex washerhead 5/16"-18 x 2", 1/2" A/F. They're three of the cylinder head screws.That strikes me as lunacy -- to have the cowl fastened by cylinder head screws.

Anyway, I've got the cowl off, and the ignition system appears to be solid state, so I don't have to worry about breaker points maintenance.

And by the way, I was wrong about the governed speed controller being riveted to the cowl; it's riveted to the same flange that the cowl attaches to -- it's not attached to the cowl at all. So my earlier exercise in installing a quick-disconnect was needless, really.

Here's a view of the flywheel and ignition coil.

There's no pressing reason for me to take the flywheel off, now that I know there are no breaker points to be examined, so I'll button that back up and attend to other things.

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Carburetor

Dismantling the carburetor revealed nothing amiss. I flushed it with solvent and blew it out/through with compressed air. The model number embossed on the carburetor's body is "1085 H6H".

Governor Link

I straightened the bent governor link, and moved its lever-end connection over to where the throttle butterfly is now afforded full travel.

Fuel Delivery Tubing

'Tidied it up. Deleted the oversize paper element filter and replaced it with a smaller mesh filter that I had on hand.

The tubing is all 1/4" I.D.

Keyed Kill Switch

It's back in place with a ty-wrap securing it.

Discharge Chute

Reassembled with proper carriage bolt fasteners, instead of the truss head screws that it had in it. Lock knob relocated to left side. Lubricated with roller chain lubricant.

The machine is ready to go outside, where I can run it up properly and see about governor and carburetor adjustment. An oil change is in order as well.

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Oil Change -- MONDAY, APRIL 22, 2019

In my area, winter temperatures seldom go below zero Fahrenheit (about -18 Celsius), so 5W30 oil is fine. For temperatures consistently below zero Fahrenheit, Sears recommends synthetic 0W30.

The hexagonal oil drain cap takes a 5/8" wrench. You may need to grip the oil drain tube with Vise-Grips to prevent the tube from unscrewing instead of the cap.

Nowhere could I find an oil capacity figure. My engine took 600ml (about 20 fl. oz.) to fill.

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Shear Pins -- THURSDAY, APRIL 25, 2019

As is so often the case on old snowblowers, the shear pins on this machine were a kluge. Here's a view of one of the 'shear pins'.

That's an SAE Grade 5, 1/4"-20 screw employed as a shear pin. SAE Grade 5 is pretty tough -- not something you'd want to rely on to shear when it's supposed to. I got the proper items from the small engines place in Pickering.

1/4"-20 x 1 3/4" hex head screws with collars and Nyloc hex nuts. The collars go under the screws' heads, and fit into oversize holes in the augers' axle sleeves.

The finished installation looks like this.

The screws' heads are marked "307A". 307A indicates a screw hardness nearly equivalent to SAE Grade 2 -- a relatively soft, low carbon steel. There's a technical note on 307A here.

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Why The Collars And The Oversize Holes? -- THURSDAY, APRIL 25, 2019

The only reason I can think of is so that no amount of tightening will squeeze the auger axle sleeves down onto the auger axle shafts; i.e. 'clamp' the augers to their axles.

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To be continued.

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