Cam Chain Shrunk!

Reminds me of an episode many years ago. I dropped in to a mate's place where he was assembling his Honda CB350 engine. He was standing there staring at the motor with a stunned look on his face. I asked him what's up, he said he just dropped the cam chain spring clip into the engine. We messed around with torches, mirrors, magnets, etc. for a couple of hours but all attempts to retrieve it failed. Took the head and barrels off, still couldn't see it. We were about to bite the bullet and split the crankcase. Turned the engine over to start undoing bolts and there it was on the bench. He was convinced it had gone down the guts of the engine but it must have bounced off the camshaft or something.

Moral of the story: Unless you're 100% sure it went down the hole, do a close inspection of the floor and bench before stripping the engine.
 
I did a quick service on TOG a long ime ago and was horrified to see that the spring link had removed itself from the chain and was "gone",the real bummer was that the shims were OK and had not moved,but the spring link had to be found, so I fished around in the sump and easilly retrieved it, I had probably re-used the old spiring clip (NEVER DO THIS) in those days I might have cared less and was even tighter than I am now but I repeat NEVER, NEVER, REUSE THE SPRING CLIP.and while I am at it never use a new joining link and side plate, always use the old one with a new spring clip,untill its time for a new chain and then renew the whole thing, since the pins wear on the chain and the joining link, you want them to be all the same.The lucky thing for me is that the side plate had not come off !!! and I dont know how long it had been like that, with a cheap chain, that had been a sloppy side plate it might have been very different, so thanks Andy for always suplying us with the best products,, the day after I bought 20 joining links/clips
CLEM
 
laverdakeith said:
There is a good chance it could be lying on one of the windage plates, if so a magnet will not be of very much use.


    Keith
Click to expand...
Windage plates?  Uh....what are those?  ???  Cuz, so far, none of my magnets has come up with the bugger.

Yeah, I looked all over the bench and floor in hopes that it had not gone down the hole.  I'm 99% sure it went down the hole. 
 
The 120 degree motors have pressed steel windage plates in the sump, basically like a false floor between the sump and the crank dropped "things" can end up there.


    Keith
 
laverdakeith said:
The 120 degree motors have pressed steel windage plates in the sump, basically like a false floor between the sump and the crank dropped "things" can end up there.


    Keith
Click to expand...

Yeah, I found that.  Seemed like a promising location for the plate to have landed.  I've searched it with the magnets, but so far, no can find.  The search continues, but this still seems like the best place to look.
 
Going to plug it up and put some gasoline in to swish around and maybe loose the bugger from it's hiding place.  A couple of big magnets on the inspection cover and the filter should attract the bastard, SOB, prick. 
 
Dellortoman said:
I'm curious about how the swishing will be accomplished. You're going to need the Incredible Hulk to drop by so he can pick the bike up and shake it about.  :D
Click to expand...
Motor is out of bike, but still....  I was thinking of hoisting it in the air and swinging it around a bit, maybe rotating it as violently as I can.  It won't be very elegant, that's for certain.
 
One question about this plan, though:

Is using gasoline a good idea?  Maybe I should use something oilier, like diesel?  Any chance I am going to damage something by using a solvent?  Cleaning off the main bearings/rods?  I was thinking of refilling the case with a couple gallons of 10W30 afterwards to make sure any lube that is dissolved will be replaced, but I'm not sure that would help much.

Perseverance hasn't completely died, yet.  I'm still fishing with my magnet assortment.
 
Don't bother with lots of oil.
Don't worry about effect of the solvent you use.
I would prefer diesel to petrol, less likely to be overcome by volatile fumes.
Wouldn't it be simpler to open the engine to retrieve the part now the engine is out?

I dropped a link once down the cam tunnel, didn't have half the bother you seem to be having.
Got it out with a magnet on a telescopic stick.
Just get on with it, we want to hear about the finished bike being used...  :D :D :D
 
Grant said:
Don't bother with lots of oil.
Don't worry about effect of the solvent you use.
I would prefer diesel to petrol, less likely to be overcome by volatile fumes.
Wouldn't it be simpler to open the engine to retrieve the part now the engine is out?

I dropped a link once down the cam tunnel, didn't have half the bother you seem to be having.
Got it out with a magnet on a telescopic stick.
Just get on with it, we want to hear about the finished bike being used...  :D :D :D
Click to expand...

Sounds easy.  Hasn't worked that way, so far.  I'm not practiced at splitting the cases, so that seems a bit overkill for the little bugger.  I'm not sure getting it out is actually that important.  If it's not on the sprockets of the cam chain, where could it go to cause trouble?  It's not like it's going to be floating suspended in oil when it's running.  It'll be on the bottom, somewhere, sleeping quietly..

Not saying I'd rather leave it there, just saying, practically, it's probably not an issue.  Comments?

Please, talk me into leaving it in there.....  :D
 
Learn a new skill.

The likelihood is the link would give no trouble in practice but potentially it could move and get caught in something like the camchain, gearbox etc.
I saw a lower crankcase half that had been welded across the left hand main bearing support. Turned out the DPO had used a cam bolt to turn the camshaft round when setting the camchain up and when the engine was running this loosened off and wedged itself n the crank bearing/support area, busting the crankcase half.

Don't use ignorance as a defence, get it out. You know it's there, which is different to finding one there by chance when the cases are split.
 
Yeah, it's got to come out.  No problem, there.  Peace of mind, if nothing else.  Besides, it's the right way to go.  I got some more magnets today while I was in Denver.  Lots of magnets magnetized together into sort of a tube.  They attract a chain side piece from 4 cm away.  I'm gonna move them around inside the bottom of the case to see if I can find it.  If not, I'll try blowing compressed air in through the top where it fell. If that doesn't work, I'm going the diesel fuel route with magnets inside the case. I have dedicated the whole day to getting that bugger out.  If none of this works, the cases will have to come apart and I'm sure I'll need more advice at that point.

 
http://www.ebay.com.au/itm/Facom-827-M-Flexible-Magnetic-Retriever-/321380966307?pt=Motors_Automotive_Tools&hash=item4ad3cc5fa3#ht_283wt_1127

Maybe one of these would help?
 
chrisk said:
http://www.ebay.com.au/itm/Facom-827-M-Flexible-Magnetic-Retriever-/321380966307?pt=Motors_Automotive_Tools&hash=item4ad3cc5fa3#ht_283wt_1127

Maybe one of these would help?
Click to expand...

Got one very similar.  Too large a magnet to go through the tunnel.  I works from underneath, though.
 
Go to a pet shop and buy a mouse. Train the mouse to retrieve chain link plates (shouldn't take more than a couple of months - mice are quick learners) and send him in through the oil strainer hole. He'll need a little helmet with a lamp on it.
 
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