That early big end failure may have something to do with very wide throttle openings at low revs when the oil pressure is relatively low. Some folk will not change down.
That's what happens when the customer "helps you" work on the engine. It costs more to fix it. Wonder if the customer started it up dry. No oil. All the work and it only took the customer a few minutes to ruin it.
This engine is def testing you paul. Lets hope when u crate it to go home this time.the currier comes in proper van and engine stayes home in its bike frame too
Hi Paul, I had a similar problem many years ago with a circlip coming out on a Norton Commando. It rested against the side of the bore and left two distinct grooves down the barrel leaving the piston undamaged. The fault was a too shallow circlip groove in the piston so it was still scrap even though undamaged. The big end failure surely must be related to the circulation on steel filings…I assume the oil pumps will have wear as well.
G'day from Australia, l was striping down an ES2 Norton the l had just bought cheaply as it had a real bad rattle and found both clip missing and the same type of scraping down the boar, that clip on that motor didn't pass through engine it would have caused more damage, cheers mate, Neil.
I am not convinced that circlip was dropped on assembly. If you had found it unblemished in the sump maybe, but it shows great wear. Also not convinced the crank rubbing on it caused the wear. The gudgeon pin coming out should (at first) cause only two parallel gouges, which would widen as the pin bit deeper. It would leave the bore in-between the gouges untouched, that is until the pin bit so deeply that the whole pin came into contact. From the looks of the bore something was rubbing in-between the two big gouges. Perhaps the clip was held by the pin against the bore until it wore thin enough to escape? Can we have a real close look at both bore & clip again? Always very interested in your good work. Keep it up.
Well, a bit of a nightmare Paul, this one, but agree with you, crclip couldn't have come out the piston withought marking it. I'm quite unfamiliar with these engines, I just wondered if there was a roller bearing conversion for the big end, like the Cub ended up having? anyway, I'm sure it will be fixed, cheers Dave
the gudgeon pin hole is not central to the conrod I noticed . . .so is it like that for any reason . . .like does the piston get to the top of the bore???
@@paulhenshaw4514 they could, but from my experience with big Suzukis GSX crankshafts are unburstable ( roller big ends and mains ). This floating bush is original RE i invention, or Indian improvement on a roller big end?
I know of a standard floating bush reaching 80,000 miles, with virtually no signs of wear. That can be seen in another of my videos. This floating bush appears to have stopped floating, or spinning freely relative to the conrod eye and crankpin, and that is probably what saw it off. The same situation would reduce the life expectancy of a phosphor bronze one, too.
in a way ..its lucky a lot more damage wasn`t done paul, some odd thing can happen in an engine and thats as odd as it gets considering thats where all the force is generated, !
And one more thing, if the timing shaft is having that safety valve.. it may foul by chance.. if so the floating bush lack oil pressure.. here we will close that valve permenantly and the system will remain as before 2004.. full pressure will go to floating bush. ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-m4MsUUMuanQ.html
Not to my mind - the relief valve is best kept. British engines all had them and I have yet to see one which has caused trouble. A relief valve opening can save the oil pumps drive train when an engine is cold, or revved hard before fully warm - I would rather have one in place any day, but other opinions are available.
Have you not got crank case separation tool? Bit surprised to see a screwdriver. That piston would've seized if that circlip got trapped twixt piston and bore. s So someone dropped a circlip at what point on the rebuild (or it fell out when they slid the barrel down!)and couldn't be bothered to take it apart again???!!!!
I have a photo showing that circlip firmly in place when I last rebuilt it, I don't lie and the screwdriver works fine when one side of the crankcase gasket is greased for easy separation next time, thank you.
Ah - ok, thanks for clearing that up, I really have no explanation for this from the point of view of what I did with the engine, but thankfully my photos - I take loads for each job - show I fitted that circlip correctly, but there it was in the bottom of the engine with not a mark on the piston. Very strange.
