I put a K&N universal filter on my bike today. I had to drill the back of the filter and put a nut and washer in there to mount the brackets that I made to mount it.

Took it out for a test ride and all was fine then setting idle all of sudden the engine reved up on its own and then smoke form under the seat and ping ping ping and I shut her down and found that the nut on the inside of the filter had got sucked into the carb HOLLY HELL SOMEONE PLEASE TELL ME I DIDN'T DIDN'T DO MAJOR DAMGE TO MY ENGINE ??

How will I get it out could a nut M-6 go through the carb and into the engine ??

You're screwed dude.... That's why I used nyloc nuts. You might be lucky and it is still in the intake valve pocket. Pull your carb, manifold & take a look.

Bummer...

Doesn't sound good.

I'd do as fireman suggested and take the manifold off. You should be able to fish it out with a magnet.

Doc

Aluminum heads and pistons, and steel nuts, don't mix well. Pray you can get it out, without tearing it down, with a small magnet on fishing line (whatever you do, don't lose the magnet in there too!)... then do a compression test after you've buttoned it all back up. If compression's good... never look inside. It can't be pretty.

I also used nylock! I think I also put the bolts through the back of the filter from the inside.

I sure hope everything works out alright for you. Please let us know.

At the worst case what could I be lokking at for damage and cost to repair ?

Wow! I am so sorry to hear that.

If going through the manifold doesn't work, then I think I would start researching what I need to do to get a good look into the head it ended up in. I'm not sure if you can pull off the head without pulling the whole motor or not, but I hope so. (Someone chime in.)

If the nut went all the way into the cylinder, it may have damaged one of the intake valves or more. Possibly the cylinder wall.

Even if it did get into the cylinder, it is still possible there is no damage. Just find it, get it out, take a good look for nicks and scratches on the valves and anything else you can see. If you dont see any evidence of damage, maybe there isn't any.

After you find it and get it out, check out the valve seating. Try to see if the valve is bent at all. If it is, stop, you need a valve replacement at least. If not, put everything back together and try it out. If it runs rough, stop, you probably need a valve replacement at least.

Hope it work out well.

dcoley wrote:
[quote]all of sudden the engine reved up on its own and then smoke form under the seat and ping ping ping quote]


Sorry but ping = damage I would try and fish it out through spark plug holes with a magnetic screw driver.

I would start from the carb and work my way to the cylinder heads by removing the manifold in an attempt to find the missing nut. Remove the exhaust and look into the exhaust valve ports with a small bright light through the spark plug holes. If you can determine which cylinder it's in, you may have to remove the affected head to get at things.

You could also remove the spark plugs and turn the engine over with a wrench to see if it will still turn without "feeling" damage.

If it is lodged in a valve, try to determine if in the valve seat area BEFORE you remove it. If yes, you may need a seat re-grind or replacement of the head.

If it went into the cylinder, it may have punched a hole through the piston head and/or damaged the cylinder head, since they are aluminum and there is little clearance in a number of spots where those two come close together.

Start looking...

Don't be too freaked... yet. Like I advised, slip a magnet down through a plug hole on fishing line. Put it back together and run it 'til hot, and run a compression check. The cylinder walls are ceramic... very tough stuff. The head can get all knicked around, and even a valve face somewhat, but if the valve edges and seats are okay, they should still seal fine. The squish zone can be pretty tight, and the greater danger might likely be a holed piston... and a compression check would reveal that instantly, as there won't be any.

If full compression is there... just run it. Don't look back... and give thanks to God!

I lost a bolt into the carb of an old Cobra Snow sled (back when they had no aircleaners, just a rubber horn sticking out there. We tried to make a homemade air filter setup, which included a bolt and a nut, that later came apart from vibration, and got suckked in while doing 8,000 rpm. It was a two-stroke engine. It smashed the skirt off the piston and scarred the crankcase up a bit. (And made some major noise.)
After fishing out all the broken pieces, we put her back together with the damaged parts and run her for a few more years.
Thankfully I learned my lesson on an old pelter.

I feel for you on this predicament there buddy, I hope yer bike is not damaged too much, maybe the nut is only stuck in the intake valve... ....HOPEFULLY....
If nothing's bent, you can easily run with a couple of dents in the piston or head.
Good luck on things, I hope it all works out.