Working toward the day....

... that I can sit in this seat again... give it a kick and drive off into the sunset.

Rear Drive Teardown

I started to tear down the rear drive unit.  The seals are shot, so the whole thing should be taken apart and inspected before I put new seals in.  The U-joint gave some trouble in removing it from the flange.  I had to drench it in penetrating oil for a few days before it would come apart, and even then it took quite a bit of persuasion with a putty knife and hammer.

The brake shoes gave me a little grief in the removal process, so I ended up making a tool to remove the shoes without getting any fingers pinched, etc.  I don't know how I functioned without a MIG welder in the past.

Clutch Pushrod Dims

Thanks to Wilhelm, Howard, and Tom of the ClassicGlory Yahoo group... for the insight into my missing clutch pushrod.  I have enough information now to fabricate a proper replacement.  It should be super-cheap to do.  I have some roller shafts I took out of some old laser printers.  Its hard-hard stuff.... but should be machinable in the lathe.

I was going to use eMachineshop to make one, but the cost was a little more than I could bear for a one-off.

Added....

Here's my makeshift clutch alignment tool.  Craftsman 5/8" deepwell 3/8" drive socket with a bolt thru the middle.  The washers bend and self-center as the bold and nut are tightened.

Big Ends Wear Limit?

What's the big end wear limit on a S7 de Luxe engine?

Please don't say 3 thou.

Somebody HELP!!!

I saw someone quote the max allowable oil clearance on the big ends is between 1 and 2.5 thou.  So I'm screwed if that's the case.  I'll need oversized bearing shells and the crank will need turned down.

The pressure bypass check valve looks good.  I tore into that, and saw that it was clear from blockages.  There was something that looked like a hair in there, but it didn't seem to be up in the ball... just wrapped up in the spring.  It seems to hold pressure in reverse, so I'm calling it good.

Oil Sump Muck

After re-assembling the gearbox it is time to get into the almighty engine.  The oil leaking down the sides of the pan seemed a good place to start... hoping that I could reach the oil pump bypass check.

The level of grime was about right for 50 years of non-detergent oil.  I didn't find any big chunks of metal, but there was grit and a few small shards of something.

There are drawbacks to the non-detergent oils of old, but at least the goopy gunk does settle to the bottom.

I hope that none of this migrated into the oil pump.  I'll be pulling the check ball next since it is accessible without taking the timing cover off, and then I'll gap the bearings.  If those both look good then there's no smoking gun to the low oil pressure.

Porsche Conversion

A weak area of the XS650 engine is the valve adjuster rockers.  The adjuster provides a small area of high pressure to actuate the valve.  This combined with limited oiling causes premature wear and pitting of the valve stem and adjuster screw.

One method to mitigate this is to intall Porsche 911 "elephants feet" adjusters.  The conseuqence is that the rockers need to be machined down 4mm on the threaded side so that the socket part of the "elephants feet" adjuster fits.

First I disassembled the head.



Then the adjusters were machined off precisely (with an angle grinder), and kept cool by plunging the part in water occassionally.



The result is a quiet running engine, with increased life.

God Bless Stewart Engineering!

What would a Sunbeam owner do without Stewarts?  I just got my second shipment from across the pond.

I double-checked AFTER I ordered... again.  And found that I forgot to order the kickshaft seal. Grr.  Aw well, I will need other things anyway.

The current shopping list:

• 2x Bellhousing dowels
• Kickshaft Seal
• Clutch Pushrod
• engine rear mainseal (maybe buy a front one too anyway)

.... will I need bearings?

Gearbox teardown

Well, the gearbox leaks like a seive.  No way the oil is going to stay inside and I can't tolerate leaky equipment.  From the look of the side panel, the box has been apart before, the screw heads are buggered slightly, and I had to make one replacement.  No doubt the responsible party just used the original gaskets with some schmutz on them to re-assemble.  So that means not only will I have to install new shaft seals, I need to make a few gaskets.

The bellhousing nuts are too close to the casting, making installation and removal difficult with the box spanners that I have.  I managed to get them off, simply because the prevous person did not torque them down properly.  The top stud came out of the block, so I blue-loctited it back in.

My plan is to slot the nuts across the flats, and use a big-ass screwdriver to tighten them.  (A possible alternative is to weld a smaller nut on the back of the bigger one, but I think that would just look weird.)

Most of the grease and oil seems to be coming from the engine.  The bad news there is that I HAVE to take the flywheel off now.  I don't have a flywheel centering tool, and I'm not exactly sure how to do that.  I do know that if its not centered correctly, it won't re-assemble easily or at all.  My plan is to make a centering donut out of some relatively thick plastic.  I can put it in a chuck and cut the outside diameter to match the inside dimension of the pressure plate.  Then I can cut the inside of the donut to match the hub of the clutch disc.  Its going to be a lot of extra work, but I want to insure that everything goes together properly.

It also concerns me that there are no bellhousing stud dowels (part P1/215).  What did that do to the clutch and pressure plate?  Was this the contributing factor to the pushrod failure?  Must order two of those from Stewart Engineering.

Frelling Frickin' Grrrr.  Big problem I noticed right away.  The clutch pushrod is mangled.  Its supposed to have a square head that fits in the clutch plate.

I noticed that the rear push mechanism was out of grease when I cleaned that up.  It appears that the pushrod was wearing pretty badly.  Not sure where the square end got screwed up, but that's going to need either replaced or repaired.  From the looks of the rod, I don't even think its the right one.  I think its just something someone put in there to make it work.  Had the bearing in the back been properly lubricated, it probably wouldn't have failed.

Luckily everything else looks fine.  The gear teeth are all in good shape; the dogs are nice and straight with no chunks taken out of them.


Today, I didn't have time to unfasten the main assembly from the casting, but I did take the rear propshaft out.  It was absolutely fithly in there.  The coupling donut (don't you just love that Hillman Imps have donut couplings too!!!) came out rather easily with a few taps.  It went for a quick spraypaint to protect the plates.  I may put some silicone fluid on the rubber to soften it up and let it expand.  Its rather dried out, and I'd rather not replace it unless I have to.

Anyway, the propshaft nut was REALLY tight.  I didn't want to put undue stress on the dogs by locking the transmission by actuating both 2nd and 4th gears at the same time.  So, I put a WD40 cap under the high gear fork and got out the impact hammer.



I braced the propshaft joint with a big ass screwdriver against the casting.  Luckily the propshaft nut was 13/16" SAE and I managed to get it off with the pneumatic impact hammer.  There was plenty of crap in the shaft seal, and I'm glad I'm going to all this effort.  I think I spent more time cleaning the various parts of the gearbox than the actual disassembly.