The feeler gauge snapped off. :(

S

Sunspark

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This has not been my year so far. Job ended yesterday too. Today I was checking on the valve when the feeler tip snapped off when I was on the intake.

I can't see it anywhere on the ground and didn't see it fly out so I have to conclude it snapped off inside as I was holding it at the time. I can't see it inside. Tried shining a light to see but I can't.

This is a picture of the piece that is missing (0.08mm/0.003" thickness) on a sheet of paper with a pen for scale (I had a second one I accidentally snapped in my hand): https://dl.dropbox.com/s/mthu11r11zlq16z/Photo 2014-05-28 20 12 00.jpg

I'm going to have to open up the head aren't I? I have the shop manual which is a starting point. I'm just dreading how far I might need to go and then have to re-do the gasket with a sealant.

I haven't started the bike obviously but I did need to wheel it away from where I was.

:(
 
Would it really fit into that little valve porthole that also contains the rocker arm? Due to the flatness of the piece I'm also worried it may have slipped potentially under the valve and falling onto the piston head below. It would have been closed when this happened but I had to push the bike away.
 
I really mean no offense... but I think you might be using feeler gauges wrong? They're not supposed to withstand much force/pressure
 
May as well try a magnet to fish it out. Nothing to lose.

if it doesn't work, on your motorcycle, can you remove the valve cover without removing the motor from the bike frame? (On my bike, the motor needs to be removed.)
 
It's a TU250X, right? On the plus side, the only way it could be easier to remove & replace the head is if it was overhead valve... that said, there is no way that piece is going to fall through the hole for the valve stem. It's around there somewhere, start fishing.
 
Sunspark said:
Would it really fit into that little valve porthole that also contains the rocker arm? Due to the flatness of the piece I'm also worried it may have slipped potentially under the valve and falling onto the piston head below. It would have been closed when this happened but I had to push the bike away.
Click to expand...

It is in the head cover. It WILL NOT fall into the piston.
Remove the cover, find the piece, replace the cover. If you don't wreck the seal, just re-install it, no sealer, no silicone.
Should be simple.

You have WAY TOO MUCH pressure on that feeler gauge.
 
Sunspark said:
Would it really fit into that little valve porthole that also contains the rocker arm? Due to the flatness of the piece I'm also worried it may have slipped potentially under the valve and falling onto the piston head below. It would have been closed when this happened but I had to push the bike away.
Click to expand...

Which bike are we talking about here ...

If you are using feeler gauges to check valve clearances, it is impossible for a broken piece of a feeler gauge to get to the "piston" and also, unless you had the carb / throttle body / exhaust removed from the engine, it is also impossible for it to have "slipped under the valve".

Pushing the bike with the transmission in neutral or the clutch pulled in does not make the engine rotate, either.

If you DID have the carb/throttle body off, and the broken piece went into the intake runner, fish it out with a telescopic magnet. You can buy a suitable fishing tool at any tool store, Canadian Tire, Princess Auto, etc.

It is much more likely that the broken piece is still lying somewhere on top of the cylinder head in the area exposed while the valve cover is removed.

If your engine has the spark plugs down in holes that are exposed with the valve cover off, don't neglect the possibility that it has gone down there. Again, a telescopic magnet is your friend.

It is highly likely that the piece has gone into the area around the valve spring, since that's close to the area where clearances are normally checked. If this is an engine that has rocker arms, you should be able to see the valve springs and look into them. If it is a shim-under-bucket engine (and you are using the wrong terminology) then the springs are not readily visible but also the bucket will stop anything that big from getting down there. It COULD get into the area underneath the buckets ... there's another area down underneath the buckets where the valve springs are exposed (basically, a passageway for oil to drain out).

I would not be starting that engine with a loose unaccounted-for chunk of metal in an unknown location.

I agree with the statement that if you broke a feeler gauge, you were using it wrongly. There should be no need to ever apply any great force to them. They should never be sharply bent to get around a corner, either. (Or, you were using a crappy set of feeler gauges that were made from the wrong material.)
 
Taking off that cover to retrieve the broken piece is no big deal. Probably several folks could offer assistance. Where abouts are you located?
 
It is my fault, I did bend the Motion Pro feelers a bit more to make them fit the tight angle a bit better for the intake so they wouldn't enter at an angle which probably fatigued the metal more and perhaps a bit too much force on the larger size feeler. I was trying to dial it in "just right" where middle goes in and out easy with a bit of drag and high goes with friction and 1 up outside the spec range doesn't go in.

It is a single cylinder SOHC engine (TU250x) with rocker arms and locknuts. While the transmission is in neutral, I believe that turning the rear wheel will make the intake and exhaust valves open and close as the crankshaft is being turned with the movement of the chain this is why I believed it may be possible that a piece 0.08mm flat may have slid through.

I'll have to start with a magnet. I hope I can find a really thin one that is flexible. I'll check the usual suspects, Royal Dist catalog, Cdn Tire, Princess Auto.
 
I'm in Oshawa. I'll be checking my shop manual after dinner to see if it has good pictures I can share.
 
If the bike is in neutral the motor does not turn over when you move it no matter what the layout/design is. If this were to happen, as soon as you started the bike it would try to drive foreward.
 
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The intake valve is the one visible in the middle of the page between the numbers 3 and 4. Now I am nervous because it looks like it could potentially have flown under the camshaft or even down below where the chain goes. Oh boy.
 
Just pray it doesnt fall into the cam chain tensioner area(if thats what im seeing). To remove that head is easy and to put back is easy. You need a torque wrench and torque each nut/bolt to spec.
 
-Echoing what Brian said, that bastard is probably still just sitting in the top of the head. Get a flashlight and some tweezers or something. The number of times I had to fish dropped 9mm valve shims out of a head...

-If it fell down the side, that's not the end of the world. If you can't see it down there with a flashlight then it may have fallen into the crankcase. If you're lucky you will get it back just by draining the oil. If not... oh wait. The TU250X doesn't have a separate oil pan? That could be bad

-There is absolutely no way it's fallen into the cylinder. It's not going to happen. Even if the valves opened and closed (which they didn't, see below), you've got to remember that the part of the valves that are opening and closing are on the other side of the head! The bore for the valve stems -- which is the only part of the valves that protudes into the open top of the head -- would be too small to pass that piece, even if that bore was not occupied by the valve stem.

-It is technically possible to rotate the crankshaft & valvetrain by pushing a bike around, but it has to be in gear, and there's no way you won't notice that. It takes a ******** of effort if the spark plugs are in, and still noticeable effort if the plugs are out. (You may not have multiple spark plugs, I am too lazy to check, it doesn't matter). Pushing the bike around in neutral will rotate the drive chain and the output shaft of the transmission, but that's it. Pushing the bike around in gear but with the clutch in won't rotate the engine either.
 
Sunspark said:
This has not been my year so far. Job ended yesterday too. Today I was checking on the valve when the feeler tip snapped off when I was on the intake.

I can't see it anywhere on the ground and didn't see it fly out so I have to conclude it snapped off inside as I was holding it at the time. I can't see it inside. Tried shining a light to see but I can't.

This is a picture of the piece that is missing (0.08mm/0.003" thickness) on a sheet of paper with a pen for scale (I had a second one I accidentally snapped in my hand): https://dl.dropbox.com/s/mthu11r11zlq16z/Photo 2014-05-28 20 12 00.jpg

I'm going to have to open up the head aren't I? I have the shop manual which is a starting point. I'm just dreading how far I might need to go and then have to re-do the gasket with a sealant.

I haven't started the bike obviously but I did need to wheel it away from where I was.

:(
Click to expand...

STEP ONE

Try magnet, give it lots of time, listen to the music, have a beer, play with it.

STEP TWO
if you find nothing, drain the oil and drop the pan, look for it there.


I once dropped a screw bit, found it in oil pan.
 
Magnet no good in part due to springs being magnetic. Decided to take cover off. I have now run into a problem. The sealant is like glue. I can't figure out at the moment how I can break that seal. The shop manual doesn't give instructions on where/how to break sealant.
 
This is what I'm dealing with in terms of trying to figure out how to get the cover off the sealant without damaging stuff.

Photo%202014-05-29%2013%2011%2057.jpg


https://dl.dropbox.com/s/6ph6nkzdd146xl9/Photo 2014-05-29 13 12 33.jpg

The path shown in this diagram is how the sealant is applied:

https://dl.dropbox.com/s/n890o9igucqfvv2/Photo 2014-05-29 13 25 57.jpg
 
Ooooohhhhh... the valve cover has ports in it! Suddenly things make a bit more sense. I guess they want you to do valve adjustments often. :P Sometimes valve covers can be a bit sticky, there's usually a tab on them that lets you pry them off (albeit CAREFULLY). Yours looks like it has such a tab on the rear right side.
 
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