GB is not OK!

[RogerSB]

Seen similar chunks in the bottom of a printing press recently when a bearing gave up.

Never had that with Bremner or Arab platens or Wharfedales

[Greybeard]

A collapsed main bearing would be the best for me as I would not need to be fitting and reaming bushes.

[morris]

Seen similar chunks in the bottom of a printing press recently when a bearing gave up.

Never had that with Bremner or Arab platens or Wharfedales

They don’t make ‘em like that anymore sir!

[Greybeard]

Might that junk be from a piston pin bush? Though I imagine the sound of a blown small-end would be pretty obvious.

Flippin-eck, already on page 2 and I haven't even started yet!

[muskrat]

Don't fret GB. What will be will be (should do a song like that  ). We all like a juicy postmortem, just a shame it happens to be a forum member at the start of the riding season.
Just had to delete a thought as to not instill further anguish.
We're all hopeful of a speedy recovery.
Cheers 

[Billybream]

What bad luck, let's hope for a speedy recovery for your old girl.
More of the kids inheritence will have to be spent to get her fully fit as it looks like the mains bearing.

[kiwipom]

hi guys, GB sorry to see this happen to you it is probably going to be expensive.  I was thinking that it could be the cam bush (25) coming loose and bits of it chomped off by the cam lobe with bits being spit over the cam trough.  I would have expected to see bits of Ali as well if it was the main bush.
  In any case a complete strip down to fix i would think so good luck with the time consuming job, cheers 

[Greybeard]

Ok, some news. I have the head and block off. The metal is from the timing side little-end bush. The bush has been spinning in the con-rod.

I can also see that the camshaft and followers are buggered. I have a new camshaft that I bought from Andrew Guttman a while ago because the cam I put in the engine when I restored it was an old one that had been reprofiled, so I was expecting trouble. I've just been too busy, (or lazy) to strip the engine to change it!

So far, I know I need a timing side con-rod and cam followers.


The wear on the cam and followers explains the rather rattly engine when it was hot!

[RichardL]

I guess time will take its toll on anything (myself, for example), but gotta wonder if lack of oil up there is a culprit, and why?

Richard L.

[Greybeard]

I guess time will take its toll on anything (myself, for example), but gotta wonder if lack of oil up there is a culprit, and why?

Richard L.

I'm pretty good at changing the oil frequently and keep the level up. I'm pretty sure that little-end bush is original. The camshaft was not a surprise.

[KiwiGF]

I guess time will take its toll on anything (myself, for example), but gotta wonder if lack of oil up there is a culprit, and why?

Richard L.

I'm pretty good at changing the oil frequently and keep the level up. I'm pretty sure that little-end bush is original. The camshaft was not a surprise.

Yep it looks like the hardening has well and truly gone on the cams and followers! You must have been doing the tappet clearances regularly 

[RogerSB]

I knew all along it was that .

  Crikey, I wonder what mine are like?

[Greybeard]

Engine is out of the bike and cases are split.

If anyone is interested I took photos of the strip. Some of them are here: https://www.dropbox.com/sh/qfpww7lt8o1bsz1/AADldGcLLg9ANq4k1ETb6Oiya?dl=0

[Greybeard]

If I cannot get hold of a replacement small journal conrod, is it feasible to have the old one bored out and a new bush made up to fit?

[muskrat]

G'day GB.
I was just about to suggest that. Any machine shop worth their salt would be able to do that. The rods in my A7 were done 35 years ago and still good. I just can't remember the correct interference fit but I'd say about 1,1/2 thou".
I'd also consider all the other bushes while it's down, especially the cam bushes.
Cheers