Author Topic: valve collet down the cam-chain tunnel  (Read 4049 times)

Offline madoc

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valve collet down the cam-chain tunnel
« on: August 08, 2012, 04:27:13 PM »

I was changing the valve stem oil seals on my CB550/4 using the string down the plug hole.
I done 7 but on the last one, the collet managed to flick out and avoid all the rags stuffing plug holes and camchain tunnel and disappear down the front hole where the cam chain runs.

removing the sump failed to find it.. (although there is a large scary piece of metal in there - but it's very clean apart from that) ...
Question is what is the risk here ?  It's a big enough chunk to cause damage.
I turned the engine a fair few times (plugs and rockers are off so it spins well) and it seems ok.....

The cam chain bottom run is above the primary chain, so it's hard to know.
The primary chain sprocket actually moves maybe 5mm side to side, which is a worry as well.


Offline matthewmosse

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Re: valve collet down the cam-chain tunnel
« Reply #1 on: August 08, 2012, 04:44:00 PM »
Fish down there with a magnet on a stick. I don't like leaving extras down there, a valve head is definately enough to make a hole in the cases but I'm unsure as to whether a collet will do dammage. You can drop the bottom cases without splitting the top end but you'll need to dismantle the cluch area so best to fish with a magnet on a stick first.
Got a 500/4 with rust and a sidecar and loadsa bits. nice and original and been round the clock

Offline Bryanj

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Re: valve collet down the cam-chain tunnel
« Reply #2 on: August 08, 2012, 04:57:32 PM »
You have to get it out as if it lodges in a chain whilst the engine is running its an engine destroying event mate. It could have lodged in any of several nooks or crannies or even be lying in the bottom crankcase, but no matter what it has to come out!

Offline LesterPiglet

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Re: valve collet down the cam-chain tunnel
« Reply #3 on: August 08, 2012, 07:04:24 PM »
Let's see a pic of this mystery metal.
'Then' and 'than' are completely different words and have completely different meanings. Same with 'of' and 'have'. Set and sit. There, their and they're. Set/sit. Bought/brought FFS. Bloody Americans.


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701arvn

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valve collet down the cam-chain tunnel
« Reply #4 on: August 08, 2012, 10:08:39 PM »
I have had some success with a Hoover to retrieve a screw dropped down the spark plug hole.

But only because I couldn't find the magnetic prodder thing.

Andy

Offline madoc

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Re: valve collet down the cam-chain tunnel
« Reply #5 on: August 09, 2012, 05:21:25 PM »
Got the collet; A tense hour with rebuild visions in my head. ;)
Bought a magnet on extendy thing; but no joy from above.
Glued rare earth magnet to bendy copper wire and fished around underneath (above primary); eventual success.

Here is the bit that was in an otherwse very clean sump (and I own british and russian bikes and am used to sludge).
It's sat next to a 5p piece.

It's snapped off something and is steel (i.e. magnetic).
Might be a tooth off a gear ?

« Last Edit: August 09, 2012, 05:24:10 PM by madoc »

Offline LesterPiglet

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Re: valve collet down the cam-chain tunnel
« Reply #6 on: August 09, 2012, 07:32:30 PM »
Looks like a dog off a gear.
'Then' and 'than' are completely different words and have completely different meanings. Same with 'of' and 'have'. Set and sit. There, their and they're. Set/sit. Bought/brought FFS. Bloody Americans.


Les Ross. Certified by a Professional

Offline madoc

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Re: valve collet down the cam-chain tunnel
« Reply #7 on: August 09, 2012, 10:59:58 PM »
hmmm.. gears seem ok. I'll see how it goes.

I put the rocker cover back on.
I backed off all the valve adjusters to make it a bit easier to seat; and then reset the clearances.
Some rockers seem to be bouncing back off the cam with a definate and loud "thunk" - just turning slowly on the kickstart.

Looks like I've bent the valves and trashed the head then ...

http://forums.sohc4.net/index.php?topic=69244.msg766351#msg766351

It's not been a good week.
« Last Edit: August 09, 2012, 11:36:04 PM by madoc »

Offline LesterPiglet

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Re: valve collet down the cam-chain tunnel
« Reply #8 on: August 10, 2012, 08:25:53 PM »
It's easy to check just by removing the sump.
'Then' and 'than' are completely different words and have completely different meanings. Same with 'of' and 'have'. Set and sit. There, their and they're. Set/sit. Bought/brought FFS. Bloody Americans.


Les Ross. Certified by a Professional

Offline LesterPiglet

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Re: valve collet down the cam-chain tunnel
« Reply #9 on: August 11, 2012, 08:40:45 AM »
Sorry brain fart. Too much weekend.  ;)
'Then' and 'than' are completely different words and have completely different meanings. Same with 'of' and 'have'. Set and sit. There, their and they're. Set/sit. Bought/brought FFS. Bloody Americans.


Les Ross. Certified by a Professional

Offline matthewmosse

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Re: valve collet down the cam-chain tunnel
« Reply #10 on: August 12, 2012, 01:31:58 PM »
You can change the kickstart shaft and with a small mirror on a stick you could get a damn good look at the gears for dammage or cracks that could indicate imminent failiure through the sump.
Got a 500/4 with rust and a sidecar and loadsa bits. nice and original and been round the clock

 

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