Hello all,
I just helped a friend try to remove a stuck oil drain bolt from his Yamaha YZ426F. We spent 4 hours trying to get this bolt to budge but were unsuccessful. I have never owned a new bike and have worked on over 100 bikes in my time, several ground up restorations and I have never failed to get a bolt unstuck. To my dismay, the owner did not even spray it with penetrating oil and he had rounded the (Must be plastic cause steel dont smear like that!) bolt head before he called for help. There is limited space to access the bolt(unless you pull the motor) so I was limited to what tools could be used. I finally resorted to drilling (Sump full of oil right above) and an easy out. I used the largest size I could and the inside of the bolt appears to be as soft type of cheese as the outside. The easy out simply bit until enough torque was applied and it would just slip---until 1/4" of the tip(can I say that on this forum??) broke off inside the cheese bolt. Now things get interesting, what to do next? Pull motor, weld an actually made out of steel nut to the head of the drain bolt or try to file the bolt flat on 2 opposing sides and try vice grips or such devices? What do the local experts recommend? I did try propane torch heat and even a freshly sharpened chisel to move this bolt(previous owner assures me they did NOT use thread lock) but she is stuck tight.

Let me know your "go to" move for stuck bolt removal--remember its shredded and drilled out.

thanks in advance for any ideas you might provide:smile-beerglass:

Its NOT left hand thread is it ?

I take it that Vise-Grips won't fit in that space. Or will they?

Take a chisel and give it some straight down taps (not trying to loosen) just straight perpendicular force to the bolt head face. They make a tool called an impact screwdriver, try to cut a slot in the bolt for the screwdriver to bite. Try heating the case and not the bolt itself. Check to see if the bolt is magnetic or not, could be aluminum or stainless (not magnetic). Some stainless bolt plating reacts with other metals and can seize if heated or left to the elements. If it’s to far gone, keep in mind what you have to loose... no shame in asking for help. Pull the motor take it to a machine shop.

PS. One last thing, if it won’t hurt anything internally or if it’s not a blind hole, try drilling all the way through the bolt... that will typically relieve some pressure of binding on the threads... then try taking an easy out to it.

Its NOT left hand thread is it ?

The bike owner had purchased a replacement OEM bolt so we are 100% sure its standard thread with righty tighty and lefty loosey. Thanks for the idea to check

I take it that Vise-Grips won't fit in that space. Or will they?

The bolt is in the little triangle shaped opening in the frame directly under the bike but it is very close to the frame on the shifter side of bike. I could only get the tips of the vice grips onto the bolt if I wanted to be able to turn the bolt with them holding onto it. I tried Heat, chisel, vice grips and even a really tiny monkey/pipe wrench which has saved me before. Everything just wipes the steel shiney like trying to apply torque to peanut butter! The bikes owner had already rounded off the bolt (possibly with too large a socket) before I ever saw the bike and all I could do at the time was try the standard things to get a bolt unstuck--even easy outs and drilling. Easy out broke in the drill hole and now it gets fun!

Take a chisel and give it some straight down taps (not trying to loosen) just straight perpendicular force to the bolt head face. They make a tool called an impact screwdriver, try to cut a slot in the bolt for the screwdriver to bite. Try heating the case and not the bolt itself. Check to see if the bolt is magnetic or not, could be aluminum or stainless (not magnetic). Some stainless bolt plating reacts with other metals and can seize if heated or left to the elements. If it’s to far gone, keep in mind what you have to loose... no shame in asking for help. Pull the motor take it to a machine shop.

PS. One last thing, if it won’t hurt anything internally or if it’s not a blind hole, try drilling all the way through the bolt... that will typically relieve some pressure of binding on the threads... then try taking an easy out to it.

Many great suggestions from a bike mechanic that seems to have some real experience with these issues. Unfortunately I also tried all of these without success.

I did many taps-bangs with a hammer and even a punch on the center of the bolt.

I also had the idea to cut a screw slot into the bolt but I cannot get anything, including a die grinder/dremmel. The bolt is recessed into a delta/triangle shaped opening under the bike between the frame and justified to one side right against the frame with just enough clearance to get a socket between bolt and frame. I tried to use a file but since the bolt is steel(possibly stainless) it would take a couple hours to cut a suitable slot unless--------->

I know I can get the bolt out if we pull the motor but with the issues with this stuck bolt, I dont want to open a can of worms with frozen engine mount bolts and other fasteners which may not have been touched since the bike was new.

My next and final attempt will be to tack weld a nut to the top of the stuck bolt and try to get it free.

Thank you for your time and response trying to help me out, really appreciate it:smile-beerglass:

how badly drilled out is the bolt?

I know you said you tried an easy out but the tip broke off, did you get the tip back out by chance?

If you still have any meat left to bite into I would maybe try drilling straight through the bolt and try a different type of reverse out/easy out. I have a few different types and sometimes one works better than another for certain situations. One thing I learned over the years using reverse outs is that I really like to use my cordless drill that has a bunch of torque settings on it. I like to start on a low setting and every time it hits the limit I bump it up 1 notch at a time. This really helps make sure you are getting good bite and not just going to strip right through the bolt you are trying to remove.

Either way, I'd just keep drilling it out bigger and trying a bigger reverse out until it either came out or there was so little bolt left it practically breaks and falls out.

Had a crank shaft nut on an old rm125 give me a fit last year, no idea how it was on there so tight. I tried everything to the point that I put enough torque on it with my breaker bar I bent/twisted the crank shaft. I ended up drilling it and cracking it off.

Well good luck

how badly drilled out is the bolt?

I know you said you tried an easy out but the tip broke off, did you get the tip back out by chance?

If you still have any meat left to bite into I would maybe try drilling straight through the bolt and try a different type of reverse out/easy out. I have a few different types and sometimes one works better than another for certain situations. One thing I learned over the years using reverse outs is that I really like to use my cordless drill that has a bunch of torque settings on it. I like to start on a low setting and every time it hits the limit I bump it up 1 notch at a time. This really helps make sure you are getting good bite and not just going to strip right through the bolt you are trying to remove.

Either way, I'd just keep drilling it out bigger and trying a bigger reverse out until it either came out or there was so little bolt left it practically breaks and falls out.

Had a crank shaft nut on an old rm125 give me a fit last year, no idea how it was on there so tight. I tried everything to the point that I put enough torque on it with my breaker bar I bent/twisted the crank shaft. I ended up drilling it and cracking it off.

Well good luck


I have purchased different style easy out bolt remover to try if I can get the broken part out. The bike owner took his bike home that day-I have 5 bikes here already--and I have not seen the bike since. He has offered to pay me to go thru the entire bike and fix what ever needs attention. I refused as I feel the bike will need more labor than the bike is worth. I offered for him to use my tools and garage to do the labor himself and I would "tutor" him when necessary. He has not returned as of my writing this post.

Socket extractor... it's amazing.

the only thing I can think of is to weld on a nut to the end of the bolt for fresh stuff for a socket/wrench to grab, then as it is cooling, hit with penetrating fluid. If it is too hot, the fluid can catch. I'd have the engine out for that one though.

I've had many a stuck bolt freed in my time just by using a propane torch and heat the case around it and then use a chissel on the out side flange of the bolt
not the bolt head itself , don't hit or mar the case just the flange of the bolt
( I think they call them cap head screws or bolts ) drain plugs always have this type of plug in them... the hex head and a flange for the "O"ring do your pounding on the flange at an angle and it will come out of there.
I use a chisel to start the place where I want to pound against then a punch...
or a flat punch ....
several times I have almost removed the entire flange by beating it away
before it finally came free... keep an eye on it if you can get it to move your almost there..... if it moves 1/4" then stops you may need to start another place in the flange so you can pound on as it turns
.... there is an art to Hammer and chisel work believe it or not, not maring the mating surface is possible....but hard to do !
think of it as your using a 1" lever to try and turn the bolt and hit it accordingly at that angle
....
I have a selection of different chisels and punches, bent punches and all
I bet you could use them now !
hang in there, you'll get it !
clean living and perseverance will prevail !LOL....:rotflmao:
Bob.......

Before he chisels away and rounds off every last bit of it, you need to weld a new extra large nut onto the stripped bolt. The problem isn't that it's too tight. It's too tight for your friend to have gotten off with his 12 point socket at a lazy angle. You have to use a 6pt socket that's dead on. Either it comes out, or it breaks the head off because it was actually too tight. If it rounds over you just didn't get a good enough grip. Welding a nut on the rounded over part gives you that grip. If it snaps off then that's perfect, because it won't have any more torque holding it in
Maybe then the chisel would work to spin it out. But I always weld nut after nut until it comes. Nothing else works for me after it's fully rounded (except vice grips on occasion when they're fully cranked down on it with gorilla grip strength)

Ducatti999 !
Did you ever get that bolt out ? I know you said the guy left and took his bike home....did he ever come back or tell you they got it out ?
.....
Bob....

I've always liked these. Way, way better than screw-type extractors...

https://www.ninjette.org/forums/attachment.php?attachmentid=47866&d=1620580919

Also smaller set I got from Home Depot:
https://www.irwin.com/tools/screw-bolt-extractors/5-pc-bolt-grip-base-set


Reminds me of head that arrived at my shop one time....

which ones Danno ? you forgot something LOL
Bob...

sorry, didn't add photo Ioben posted.... saw squirrel!

LOL I know the problem well ! My Dog was born on the Ranch and hasn't quite got the hang of city living yet.... it's OMG BARK,BARK, BARK ! for 15 minutes when someone walks by... the cats are the ones that run across the keyboard and screw me up ! (and look so surprised when you run them out !)
....wouldn't have it any other way though.... I love my critters !
....
I have 4 of those and used one once ..... but it didn't take the bolt out it just cut the head smaller and at a taper...
.... got that one out with vice-grips and a propane torch !
Bob.......

Before he chisels away and rounds off every last bit of it, you need to weld a new extra large nut onto the stripped bolt. The problem isn't that it's too tight. It's too tight for your friend to have gotten off with his 12 point socket at a lazy angle. You have to use a 6pt socket that's dead on. Either it comes out, or it breaks the head off because it was actually too tight. If it rounds over you just didn't get a good enough grip. Welding a nut on the rounded over part gives you that grip. If it snaps off then that's perfect, because it won't have any more torque holding it in
Maybe then the chisel would work to spin it out. But I always weld nut after nut until it comes. Nothing else works for me after it's fully rounded (except vice grips on occasion when they're fully cranked down on it with gorilla grip strength)

I got a question to your post guy.... How do you weld a steel nut to a aluminum or pot metal bolt and expect it to stay ? that would be a very good trick !
the idea of doing that on a steel bolt is understood and a very good proven method of removing a seized bolt.... but even if you were lucky enough to find or buy a nut of the same metal can he TIG weld it on there upside down ? ... can he tig weld ? can he stick weld and does he have a dc welder that can weld aluminum rod ? I doubt it....
there is no easy solution apart from removing the motor so you can get at the bolt.... and the owner took the bike and left.... a bad situation all the way around in my book... no one is happy.... time wasted and the guy goes away in defeet .... and he broke an easy out .... the whole situation sucks !
.....
Bob.......

I got a question to your post guy.... How do you weld a steel nut to a aluminum or pot metal bolt
.....
Bob.......

Drain plugs have always been steel, at least I've found. I don't own anything faster than my 250. They might have a crazy aluminum or titanium bolt. I've never welded aluminum so i can't speak on how easy it is upside down. I know steel is easy upside down apart from the sparks that hit your head and body. That hurts. The bike can be laid on an old blanket or couch cushion and bolt worked on while sideways. I would not be so easily defeated in taking out the engine. This is an involved job with removing the chain, fairings, carburetor, cables, etc. But it may be necessary in the end

You can check if it can be welded with a cheap flux core steel welder with a magnet or the grind it and see sparks test

Those can be a nightmare.

But if you have access to a stick welder, you can take a short length of pipe the same diameter of the bolt head, hold it up against the bolt and then weld them together by putting the stick up inside the pipe. Once it's firmly attached, you can use vise-grips or a pipe-wrench to remove the bolt. The heat from the weld will help loosen the bolt as well.

Attaching the ground as close as possible to the stuck bolt is a good idea.

Good luck,

J~

Yah ! I arc welded the frame of a bike one time ...just pulled it up to the welder and put it on it's side stand and cleaned off the paint and welded the frame
i thought no problem I am ready to go again.... I got about a mile away from the ranch when the battery finally died and had to push it back...
the arc welder fried the selenium rectifier in the bike...so I had no charging....
I checked the alternator and was ready to find a fried stator but I got extremely lucky and it didn't hurt it at all.....
....
take the battery out of your bike before you weld on it and do not ground the positive lead to the battery.... wrap some black tape around it....
..... I know this works because I did it on my Honda 700 shadow i welded it with no problems at all.....
......
Bob....

yeah, remove battery, RR and ignitor. Might want to unplug dash too... just in case...