Metal cap found in motor

[drummer-on-a-EX]

I found a piece of metal in my motor, it appears to be a small 1/2" metal cap of some kind, it has caused a fair amount of damage, including a tranni gear and a few valves after getting caught in the timing chain, my concern is I don't want to put the motor back together until I know where it came from, it is not off of the tensioner, it is a bit smaller than that, the motor is a 05, with 88mm piston.

[FarmerTed]

Originally posted by drummer-on-a-EX
I found a piece of metal in my motor, it appears to be a small 1/2" metal cap of some kind, it has caused a fair amount of damage, including a tranni gear and a few valves after getting caught in the timing chain, my concern is I don't want to put the motor back together until I know where it came from, it is not off of the tensioner, it is a bit smaller than that, the motor is a 05, with 88mm piston.

Are you sure it's a cap? You say it damaged a trans gear and got caught in the timing chain, did you see if the piece fits on one of the teeth? Could be a chunk of bearing and is now shaped in the form of a timing of trans gear tooth after bring effectively stamped into a new shape by one or the other.

[drummer-on-a-EX]

I'm not positive it's a cap but it appears to be "pre-formed" that way and then damaged by the gears.
I split the cases and my c-5 gear is missing two teeth, I can only assume that this piece of metal at some point ran through the gears, I found the pieces of gear, bearings all appear to be good. I can't find anything missing a piece or chunck, that's what makes it baffling.

[400exMO]

Well since the cases are split go over everything, clean them up and check for wear and any other signs of fatigue. I recently lost 2nd gear in my crf450 and while cleaning everything up to reassemle the cases found many more broken parts. Check the back of the clutch basket, hub and pressure plate. I had big problems there. Good luck.

[killer400ex]

wow how did it go through the gears then into the timing chain, those 2 halves of the engine are sealed, and the oil goes through a strainer at the bottom, that is baffling, i tear these down and work on them all the time and have never seen or herd of anything like that

[Sanddraging28]

i am stumped. there is no way for it to get from the tranny gears to the timing chain.
you said it has a 88mm piston in it. that means it has been apart before. how long has it bee since the top end has been off??
any chance something got dropped in the cases???
i have no idea what it could be...any way you can post a clearer pic of it. i may be able to help

[drummer-on-a-EX]

It's hard to take a good pic becuase of it's size, this is probably as good as it gets.
I can only assume this is what chipped 5th gear, the piece of metal appears to have been stuck for a short time above the clutch basket and case cover, there is a nice groove on the outer basket and a gouge on the cover.
I had the top end off about 6 months ago but it is very unlikely anything fell in there.

[drummer-on-a-EX]

I've been looking at pictures of every piece I can, I ran across this picture, anyone ever lose the crown of a head nut? I won't know until I get home tonight but it's a thought.

[dariusld]

Originally posted by drummer-on-a-EX
I've been looking at pictures of every piece I can, I ran across this picture, anyone ever lose the crown of a head nut? I won't know until I get home tonight but it's a thought.

These are all the extra left over parts from my last rebuild;)

[drummer-on-a-EX]

Originally posted by dariusld
These are all the extra left over parts from my last rebuild;)
LOL....I've known shops that build that way.

It was not part of a head nut, it still appears to be a cap/plug of some kind that has been damaged by the timing chain gears. I've taken it to a dealer and a couple of shops and they all say it looks familiar but have no idea what it could be.
I'm about done cleaning all the parts and I can't place it, any fresh ideas would be appreciated.

[fishnfergie]

Put your camera on Macro (the setting with a flower) and the picture will be very clear.

[Tommy Warren]

Is is thin enough to be a seal off of a quart of oil? thats what it looks like to me just a thought!

[fishnfergie]

What about one of the centering dowels that help line up the bolts when putting various parts on.

[RATPACK Z400]

If you had work done on it at shop someone could have by accident dropped it in motor while they had apart and didn,t know things happen, it doe,s look like cap for the bolt in pic.

[honda400ex2003]

Is is thin enough to be a seal off of a quart of oil? thats what it looks like to me just a thought! That is the same thought I had but it looks too thick. I am still thinking about this and discussing it with others. I havent given up hope yet. steve

[RATPACK Z400]

That seal wouldn,t grind metal it,s made of somekind of paper/alum not hard metal.thats, definitly a hard metal right?

[drummer-on-a-EX]

It is definitely metal. I've cleaned every part and have no clue what it is, I've taken it to a couple of shops here in town and one guy thinks it might somekind of oil passage way plug, ???
I've got my new clutch basket and plates, valves and rings, just waiting on 5th gear to get here and I can start putting her back together, that's the scary part, putting it back together without knowing WTF that piece of metal is.

[buck440]

know if it is aluminum or steel might help to know where it came from:confused:

[davidw2155]

I bet it is one of the dowels used for lining up parts of the motor during assembly. If you are not careful when you are taking it apart or putting it back together one of those could very easily fall into the engine. I would check to make sure all of those dowels are actually there in your engine.

[drummer-on-a-EX]

Does anybody have a picture of a 05 right case, I believe it may be similar to freeze plug.

[drummer-on-a-EX]

There is a small cap in the end of the tranni shaft that some how blew out and started bouncing around the motor.
Thanks everyone for your help!

[honda400ex2003]

Wow never even knew there was a cap in there. thanks for telling us what is was. Congrats on figuring it out too. steve