www.jec.org.uk

Don't worry, not the XJ-S My Indian made Royal Enfield Bullet 500 (The Chanai Chariot) decided to self destruct on the A303.



Pistons separating are well known fault, most of the engine is made from recycled scrap metal so its not surprising really. I found a pile of metal bits in the crankcase which used to be the oil control ring, half of the second ring and a fair bit of aluminium piston. Unfortunately both valves are also bent and the con rod was peppered by the debris.

A bit of history, the Indians bought the tooling from Royal Enfield as an easy way to produce their own bikes, It is basically a 1955 model which was made till quite recently when emissions forced a change, up till them they never saw any need to update the design. The quality control and materials are how shall we say, not quite what the original factory had intended. That said, they are a quirky but relatively cheap way to enjoy '1950s motorcycling. I normally avoid motorways as any speed over 50mph is asking a lot for the big single. A point I proved yesterday!

I spent today stripping down the engine for a full assessment and its not a pretty sight. I wish I had gone out in the Jaguar now.

Pop,

Sorry to hear of your woes. Despite the fact that I have always been a Triumph man rather than a particular fan of BSA, Norton, Ariel, RE or the myriad of other Brit bike makers, I love all bikes and am still grateful that India took the Bullet and have kept the old design running for so long. It still seems bizarre that we now import REs from India as a constant reminder of our own heritage!

I'm assuming that at least you can source piston, rings, barrel, valves etc at reasonable prices and it'll remind you how easy it is to build a bike engine rather than struggling with the 6 cylinders on the XJS!

Good luck with the rebuild! You'll know it's been done properly as well!

Paul

An update, (I hope motorcycle engines aren't too JEC off topic?) I have tried to give a little general info as we go along to make things more interesting!


With a bit of soldering and a quick polish the piston was back in one piece. (Yeah right!)



I had to remove the engine and split the crankcase to get all the pieces out. It was at least a chance to check all the bearings and clean everything up. These engines are dry sump to keep the centre of gravity as low as possible. The large chamber to the left is the oil tank. The 'egg' shaped chamber at the bottom of the crankcase collects oil that has been supplied to the main bearings and barrel, before being pumped by a secondany oil pump to the rocker box at the top.



I was lucky in that the barrel had not been damaged. The aluminium con rod has taken a battering and I still have some doubt as to whether I should have changed it due to the stress weak points it now displays, however, on the Enfield it is a one piece affair and changing it would have required a professional rebuild and balance of the crankshaft which I just didn't have the money for. Fingers crossed I guess, if it throws a rod in the future its goodnight Vienna time.
So after checking ring gaps and bore diameters, its back on with the barrel.



Looking good so far. The cylinder head is next

You can't beat some good engine build pics - no matter what engine
Nice work!

Pop

After looks a lot better than before
Good luck with the con rod, I'm sure it will be fine.

I abandoned my £80.00 BSA 250 Starfire (lovely 10" 'straight thru' mega) in a neighbours garden when I left Uni.....they're worth about £3K? now....ho-hum

TonyS

The Chanai Chariot continues to give me grief! When I bought it I knew the previous owner had 'repaired' the sump drain plug with JB Weld and for some years now it hasn't caused me any problems. In fact, last year when the engine was apart to replace that pesky piston when I could have done something about it I chose not to because all was well.

A few spots of oil on the floor told me all was not well, like those adverts about blood in your pee, you instantly know this isn't going to go well. The first photo shows a hairline crack in the JB Weld.



Once I had removed the offending filler, the damage was found to be a bit more serious!



In fact it has a split around the back as well, so my winter project now is to remove the engine and split the crankcase again. Deep joy!

Pop,

Sorry to hear (and see) the latest problem. And also related to Jaguar problems, as the AJ16 sump is prone to the same damage as over-enthusiastic owners (and incompetent mechanics!) overtighten the sump plug. Mind you, I suspect it will be easier and cheaper for you to repair that with a good bit of alloy welding than an AJ16 sump!

It's also reminded me that I must sort out some spacers for the inlet manifolds on my Bonneville this winter to stop the heat soak to the carbs.

Good luck with the repair.

Paul

Hi Paul

You would better making the spacers out of tufnel that will stop the heat transfer.

John

Hi PoP Rivet,

I was thinking about your Con Rod. If you wrapped it in a blanket and got in the queue with all the pregnant mum's down at the clinic, would they do an Ultra Sound crack check for you!

Good idea, but being Portsmouth the queue would be too long
The con-rod small end hole isn't even bored in the centre, unless it was designed that way? (see pic above) Its all part of the fun, if I had a Honda life would be boring.

Update on the crankcase repair.

I took everything apart and removed anything I could but even one half of a crankcase is a big heavy lump of alloy. I had been recommended the "Laser repair system' as avaliable at Machine Mart.

http://www.machinemart.co.uk/shop/produ ... tarter-kit

If you thought it wasn't possible to braze/solder aluminium think again! It took a lot of Mapp gas to get things hot enough, but eventually the filler rod seemed to do its job. I was worried about melting the aluminium as that would have been the end of the engine, but with care it went well.

If I had a TIG welder locally I would have used him, but I like a challange. If you need to do a simple repair in aluminium I would say give it a go, but not on something really big such as a Jaguar head or block.

Photo below shows the view from below of the drain plug after the repair. Time will tell of course, but it doesn't have to hold a great pressure.



The next photo shows the engine being built up again.

well….


after seeing your results , and watching the Vid from machine mart ,

i went and bought a set of 5 genuine rods, ( ebay £12 , or 10x for £22 )

i have a very expensive aluminium time trial bike frame that developed stress cracks around the down tube boss, no on wanted to touch it as the 2005 aluminium is very thin but strong, and would risk burning back using TIG methods

so , i will give this a punt,

BB

Gearbox.

I suspected that the kick-starter pawl needed some attention as on a few occasions the lever had 'missed' so to speak, resulting in me doing a dance around the garage holding a bruised and sore ankle!

Now was the perfect time to put it right as the gearbox was separated from the engine. Gearboxes of all kinds, Jaguar especially, are not merely engineering masterpieces, no, they are indeed mystical boxes full of Demons, springs and magic. Even this relatively simple1950's design era Albion box could well have been a mystery to even Harry Potter.

First some background information for anyone not familiar with how to change gears on a motorcycle. Unlike a car where a gear stick can be moved right, left, up or down. On a motorbike, you use your foot, mostly these days the left one (The right being the back brake), but on an Enfield following older British practice the gear is on the right with the rear brake being on the left. Interesting when approaching a junction if you have forgotten which is which!

I digress, it's a sequential box and you use your foot. Lift up for 1st. Press down for 2nd, 3rd and 4th. Up again to reverse the process. Oh, and neutral is between 1st and 2nd! Who said bike riding was easy. (Especially as some bikes are 1 down and 4 up). Making sure you are in neutral or first gear when stopped at a junction takes some skill, some more modern bikes have a neutral light or indicator on the dash to help. This Albion box has a handy device, a small metal pedal called a neutral finder, which when pressed with the heel of your foot moves the gear train into neutral. Of course, your other foot may be on the rear brake pedal at the same time, which can make balancing somewhat of a challenge.

Where was I... Oh yes, the kick start pawl. This is made from sintered iron, which can be thought of a powdered iron, pressed into shape and heated until it becomes solid. Now there are engineers reading this who will know far more then me, but I guess that it is cheaper to replace the pawl rather then the gear wheel it engages when wear occurs and that any debris is less harming then shards of steel floating about in the gearbox. The picture below shows the old and new pawl. You can see why it needed renewal. The new one cost 99 Rupees from India (£1).



The old lubricant in the gearbox was a nasty black colour. Quite likely only ground up pawl dust but while I was in it this far it seemed right that I cleaned it all out and started with fresh.

Because Royal Enfields never had oil seals there, the gearbox is filled with a gloopy grease . Not any old grease mind you, Oh no! That would be too easy. Luckily at Stoneleigh Jaguar Spares day I found a tub of Castrol Spherol 00 which was correct. But first, I had to remove the old grease. There is an old Army saying about grease that sticks like $hit to a blanket. This must be that grease, but at least those old Albion engineers knew a thing or two about how to keep those gears lubed!

Much scraping, scooping out and washing in white spirit later and things were looking better. The photo below shows the main and lay-shaft with the cleaned housing, and to the right the un-cleaned outer cover to show the difference.



Just how these two shafts can provide 4 gears, of the correct ratio, and a neutral, is quite simply a marvel to be honest. To explain how this is achieved, the link below is to a graphic that shows what happens. The mechanism that transfers the up and down foot movement to shaft positioning is quite complicated and setting it all up takes some time.

http://www.hitchcocksmotorcycles.com/pi ... earbox.pdf

Fast forward now.. All re-assembled, filled with new grease and fingers crossed, the gearbox is now bolted to the back of the engine and just about ready for installing back into the frame as the picture below shows.



I doubt many of you have made it this far into this story, but for those who have you may have noticed that the cylinder head is so far missing. More epic ramblings will follow in time, to explain the problem.

Well, I never got around to explain the ending. All went together very well and it now runs a treat, it should after all the work and expence. In fact its better now then when it left the factory! However after much soul searching, I've decided its time for the Channai Chariot to seek pastures new so that I can spend more time with the XJS.

It is being advertised, so just in case anyone on here fancies it...

[EDIT: Now sold]

Excellent job Pop, well done!
I hope you get what you want for it, you deserve it after all that work.
TonyS