Sunbeam S7 clutch cable

KYL95 needed a new clutch cable. The original was beginning to fray around the upper ferrule. (I've been stranded with a snapped clutch cable and its not worth the risk.)
I obtained a Venhill universal cable kit.  It came with the following parts and a nice set of directions on how to make up the cable properly. Many of the pieces I didn't plan to use, but everything was there.
Stripping the original cable off showed the poor condition of both the sheath and cable. I was mainly concerned with the fraying, but the bends in the cable were making more slop than needed in the adjustment.
The new sheath was cut to length, and routed with the end cap that came with the kit fitted to the clutch lever.  The ferrule was slid up tight and pulled tightly by hand with the adjustment fully retracted.  The cable was then kinked to one side indicating the correct length. I then manually made a birdcage shape at the end and soldered the ferrule in place.
The cable is now straight and pulls much easier through the nylon-lined sheath.

"Project Bantam" - Tire Mounting

It turned out the best place to obtain the Carlisle Power Trac rear tires was Walmart.  They had them the following day, and there were no shipping charges.

The rims were de-rusted and the rust holes were filled in with bondo and glazing putty.  The top coat was a matte finish to hide my poor bodywork skills on curved surfaces.

 

The tires went on easily with new inner tubes.  The 4.8" width is marginal compared to the original 5.0".  They really do look good though.

"Project Bantam" - Carb corrosion

While this doesn't look too bad on the outside, inside lurks horrible corrosion to haunt your dreams.

Finally managing to coax the carb apart exposes the full horror of how much corrosion can actually enter a carburetor.  The float was split from freezing, and also made concave in one area due to the pressure of ice under it.

I've never met a float that I couldn't solder back together, and this was no exception.  I can solder anything.  It took a few hours of cleaning, careful straightening, and reforming.  The difficulty was in the brittle nature of the inner side walls.  They had to be tinned from inside and out.  I don't know if it will hold up in the long term, but its water tight now.

The final product looks fairly good. I spent an entire afternoon with the top of the carburetor in the lathe truing up the mating surfaces of the flanges.  The screw tabs were bent from over-tightening, and prevented the whole assembly from fitting together correctly without any air leakage.

It will be seen whether the corrosion of the thread holding the main jet (which prevented its removal) is problematic.  The only issue now is to set the float level and find a packing nut for the main jet adjustment needle.

On a side note, the main jet of the carb had to be drilled out to fit the new one I bought in a Stens 520-049 rebuild kit (original B-S kit # 394693).  The Stens needle valve kit 525-246 (original B-S kit # 99525) will have to wait until I can clean the tapped hole in the body with a 5/16-32 bottoming tap (once I get one).

"Project Bantam" - brass ring gear reproduction

Bob Weaver in Shelby, Ohio had a batch of reproduction brass ring gears made.  During Bob's own restoration he needed one as well, and I was fortunate enough to obtain the second-to-the-last one he had made.  The Weaver family were very pleasant folks and I enjoyed doing business with them.  The gear looks like good quality American workmanship.  That kind of workmanship is worth it, and it didn't come cheap.

"Project Bantam" - magnamatic ignition

I came across this article in Gas Engine Magazine, and I'm certainly glad I did.
http://www.gasenginemagazine.com/gas-engines/cheap-fix.aspx
The author showed how to fit a common B&S coil to the Magnamatic Ignition on this model FB engine. The concept is simple. Remove enough material from the core to make it fit under the flywheel. And it is tight.

Original Coil

After some careful hacksaw work and filing, and I think it turned out rather well. I did not use a hoseclamp like the fellow in the article. I fashioned two spring clips to emulate the original ones. I made them VERY tight, and also put a screw on one side to positively locate the coil along the shaft axis, as an added measure to make sure it doesn't wander around due to vibrations.

Modified Coil

Modified Coil and Core assembly

"Project Bantam" - gearbox teardown

The axle shafts on the gearbox were flopping around in their bushings, so I knew there was going to be some parts replacement inside.  I just didn't think it would be this bad.  I was told that the brass ring gear had been repaired once before.  That didn't console me much either, since I knew it was probably bodged back together.  My father didn't have a lathe at the time, so the previous repair would have been dodgy.

 

Opening the cover on the gearbox revealed a lot of sludge, but no broken parts.  It all came apart easily by following the overhaul instructions.  The back of the shift shaft was a little rusty, so that had to be addressed before the shift fork would come off.  Otherwise the bearings look relatively good, and I took note of the part number on the input shaft seal.  "Victor 62012", which is supposed to cross over to "Federal Mogul 470954".  The axle shaft seals were so bad, I couldn't even read them, they're supposed to cross over to "Federal Mogul 254287".

The gearbox wasn't a problem, it came apart easily from the differential.  The worm gear pulled out without any problem and showed some wear.  Opening the differential showed the horror of the main failure.

It seems a lot of the teeth had dissolved into sludge.

The spider gears look ok.  They don't seem to have any significant wear.

Cleaning everything out was a several hour process.

 

The axle bushing is obviously broken off causing the excessive wear of the teeth.

I doubt this gear salvageable, I supposed I must obtain a new (different) one...

"Project Bantam" - slow work in the cold weather

There's been limited progress the last few weeks.  The weather has been cold, so parts passing through the electrolysis tank haven't had the opportunity to be cleaned outside as quickly as I would like.  The workshop is nice and clean, but I need to take the parts outside to wash them, and there has been snow.

The seat and spring came out rust free and have a nice coat of black paint.  They will require new bolts and some washers since I cut the originals off with the angle grinder.  The mounting bolt to the body that snapped off still needs drilled out and re-tapped.

 

The tin-worm ate the fan shroud rather severely.  It will require some intensive reconstructive surgery.  More on this later.

I just set the carburetor aside for attention at a later time.

Removing the flywheel is providing a bit of a challenge.  The 1-1/4" nut came of relatively easily.  The flywheel was blocked up and I simply hit the 3/4" ratchet handle with a big mallet, and the nut came loose.  Pulling the flywheel is another story.  Its really stuck.  PB Blaster and some patience will be required on this one.  The flywheel is cast iron and I can't afford to damage it.  Another larger puller may be required.