Metal In Engine

Hi everyone,

I've got a potentially serious problem that I need to address. I've got a 2003 YZ450F. One of the 3 bolts that holds the oil filter cover in place was stripped out. Not only was the bolt stripped, but so was the bolt hole. So I drilled it, tapped it, & installed a heli-coil. The problem is...... the bolt hole is a "through hole" that goes all the way into the crankcase. When I went to break off the little "tang" on the heli-coil, it dropped inside the crankcase. It's very small, but it's metal & I'd like to get it out before it winds up wedged between a couple of gears or something. I've tried flushing it out by pouring several quarts of oil thru the engine. I've tried a magnetic drain plug. So far, I haven't seen it come out. Aside from splitting the cases, does anyone have any ideas on how to get this piece of metal out of the crankcase? Do you think it will just wind up in my oil filter?



How small is it?

It's about 3/16" long. And it's a little smaller than the diameter of the wire that paperclips are made out of.


I've found bits of metal (gear chips) about that size on my '03 KTM525's magnetic drain plug! It's your call, but I don't think it's likely to cause any damage if it's in the bottom of the cases, as long as it's not caught up in the oil flow system. Keep the magnetic drain plug in there so that hopefully you'll catch it. I've got a magnetic drain plug on order for my bike; I think they should come as a standard part like on the KTM's. Even my Chinese pit bike came with a magnetic drain plug!

i just split my '03 open.. and there's no chance of it getting sucked up into the oil pump.. there's a really nice mesh screen that filters anything going into the oil pump..

however, what my mechanic told me is that your biggest problem is that piece of metal finding its way into the crank bearings when youre at speed somewhere... you risk the crank seizing, and sending you over the bars unexpectedly..

my piston dropped a circlip down into the cases.. i just had to pull my motor and split my cases to get it out. i wanted to do it myself, because i can't justify spending $1500-$1800 to pay someone to rebuild a motor on my bike.

it's not hard at all, but it is time consuming. i had the cases on my workbench and split on the 2nd night of wrenching on it.

so, anywyas, i don't know how much truth there was to the 'crank seize' theory, but by yoru description of the size of it... and if it's a soft, pliable metal (like helicoils usually are), i'd say just don't worry about it.. if it does make it's way into the tranny, the tranny will probably just have it for lunch.

i'm not telling you to split or not-to-split the cases, obviously, you know what the right answer here is, but if you do decide to just ride it like that, just pull your oil filter after every ride and look for tiny metal shreds. if you find any, you know the thing got munched up, just change your oil/filter after every ride for the next few rides.

also, try this... prop your front wheel way up somehow (like in a wheelie position) let it sit like that for a minute or two, then also tilt it to the left about 30-40 degrees (towards the shifter). then drain your with the bike propped up like that. it's probably the best chance of it draining out via the rear plug that way.

FWIW, i found my circlip halves sitting at the bottom/rear/right of my crankcases.

good luck.. hope you dont have to go through what i did.


I had the same problem with my 03 filter bolt. You can remove the outside case/cover with engine in the bike. This will give you access to the area where the metal would have fallen. I pulled mine off before drilling for the helicol.

The problem is that most heilcoils are made of stainless steel. The magnetic plug won't recognize it when the oil it passes by it. So I would recommend splitting the right half of the engine case and locating the curly clue. Stainless steel is hard and might get into a roller bearing or between a gear and than, you really got big problems.

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