1st Engine Pull

I am currently pulling the mototr from my 99 yz400 and have run into a problem on the last bolt. It the very bottom one that goes through the bottom on the case. This thing is on so freakin tight I can't even budge it. Penetrant hasn't helped and I'm to the point where the nut on the right side of the bolt is starting to strip a bit. I don't mind buying a new one once it's off but how to get it off????? :)

It's a bit recessed on both sides so it's not the easiest bolt to get to.

Any idea's?? Cut off the nut with a Dremel? Help!

TIA!undefined

Hmm. Can you get to the bolt or nut with a cut off wheel or small grinder?

Try using a 6 pt. socket on the nut to prevent rounding it off. I think all impact-type sockets, for example, are 6 pt.

The way I always approach something like this when the situation allows is to take a welding torch and quickly heat the nut to a good bright red, trying not to heat anything else up more than absolutely needed in the process. Ideally, you will get the nut red long before the bolt starts glowing. Angle the torch to keep heat away from the frame. This will relieve the tension on the threads and break the bond that's developed between the two surfaces, and the nut should come right off after that. Just let it cool to where the red goes away before trying to turn it. It will, of course ruin the nut, and probably the bolt, too, but it works really well.

Tried both sockets Hick. Didn't work. Maybe heat is the solution. I'll try that tonight. If that doesn't work the the Dremel gets the next shot. Thanks guys!

Like grayracer said heat helps. I have done this with some crusty bolts and not had to get it as hot to make it glow but still got the job done.

I'm not sure of everything that you are doing but on a 98 yz125 swing arm bolt that goes through the motor it had seized on me. Most likely the aluminum has seized on the engine casings. No big deal. I tried heat and all the sockets, breaker bars everything and the bolt would not budge.

Try this. Duragloss the carwash company makes a product called aluminum bright. Its and acid based product that eats up all the bad crap on aluminum. I sprayed this stuff the best I could the same way you would a penetraiting oil. Let it sit for 5 mins and rinse with water. The bolt came right out.

The product will blow your mind. It you have dirt stains on your motor or hubs they will be gone. It will not harm plastic also. Read the instructions carefully and follow them. DO NOT GET IT ON ANY KIND OF POLISHED ALUMINUM, EG CHROME LOOKING STUFF. It will make it dull. But for all the dull metals on your bike you will not find a better cleaner. IF anyone else can find a product that does what this stuff does let me know cause I will buy it. HOPE I HELPED AND LET ME KNOW IF YOU TRY WHAT I SAID. :):)

If the heat doesn't work I'll give it a shot. Where can you get the stuff?

Try using a 1/2" air impact wrench before torching the nut and bolt.

I pulled the engine last night on my 00 the last or let me say lowest forward motor mount bolt that is recessed and passes through the case was a bear on my 00 it has a nut on the right side bolt head on the left, I tried with a 8' long breaker bar on the bolt head side, no luck, switch over to the nut side and it still took a good deal of motivation, thankful I had my 8' long motivator ,it gave a nice audible pop when it broke. Morale of the story get a big motivator and hit it from both sides (if a bolt is that torqued or has a little corrosion in the threads it won't spin from either side) if the nut rounds get a smaller socket you don't want any more and hammer that bitch on there and go after agian with the big motivator, I have found that a 8' breaker bar either get the nut off or break the damn bolt. Good luck

http://www.duragloss.com/product.asp?pid=270

Here is the link. You cannot find it at department stores autozone ect. Call around to the parts stores that deliver to mechanics. I think a carquest can get it. I pay $13.00 a gallon. Man if you have anything aluminum this stuff will get all the crap off and make it look new. YOUR HUBS WILL THANK YOU. SPRAY IT ON LET IN SIT FOR ABOUT 30 SECONDS AND SPRAY OFF. :)

I pulled the engine last night on my 00 the last or let me say lowest forward motor mount bolt that is recessed and passes through the case was a bear on my 00 it has a nut on the right side bolt head on the left, I tried with a 8' long breaker bar on the bolt head side, no luck, switch over to the nut side and it still took a good deal of motivation, thankful I had my 8' long motivator ,it gave a nice audible pop when it broke. Morale of the story get a big motivator and hit it from both sides (if a bolt is that torqued or has a little corrosion in the threads it won't spin from either side) if the nut rounds get a smaller socket you don't want any more and hammer that bitch on there and go after agian with the big motivator, I have found that a 8' breaker bar either get the nut off or break the damn bolt. Good luck

cheeze13...That's the same bolt that I was working last night. I got the nut off with a dremel and a good course bit. Then I just pounded out the bolt with ease. I'm leaving the front motor mounts ON on my bike. Couldn't budge them but got the engine out after a short while. I'll have them take off the mounts at the shop when it's there.

Only a few scraps and bruise's (ran my knee into the footpeg more than once!) :):)

Wow.... an 8' breaker bar!!! That is damn big.

Noticed that you said the bolt was getting a little rounded as well..... in the past I've welded a wrench on to the bolt/nut just to get it off. Of course this is a last resort for getting out stripped bolts, but it does work, all though I'm not sure how well it will hold up if you gotta put that much tourque onto it.....good luck!

Wow.... an 8' breaker bar!!! That is damn big.

Noticed that you said the bolt was getting a little rounded as well..... in the past I've welded a wrench on to the bolt/nut just to get it off. Of course this is a last resort for getting out stripped bolts, but it does work, all though I'm not sure how well it will hold up if you gotta put that much tourque onto it.....good luck!

GOod point I have seen the weld a wrench technique, and it works, last night I stripped that damn T-27 bolt on my stator, I said fu%k it and drilled the damn thing out, but when drilling with the internals still internal its a good thing to put a magnet at the base of bolt and let it catch all of your shavings... or else... and we know what that else is $$$$ new bearings and other shit. :)

I am currently pulling the mototr from my 99 yz400 and have run into a problem on the last bolt. It the very bottom one that goes through the bottom on the case. This thing is on so freakin tight I can't even budge it. Penetrant hasn't helped and I'm to the point where the nut on the right side of the bolt is starting to strip a bit. I don't mind buying a new one once it's off but how to get it off????? :)

It's a bit recessed on both sides so it's not the easiest bolt to get to.

Any idea's?? Cut off the nut with a Dremel? Help!

TIA!undefined

To make sure this doesn't happen again; make sure to put anti-seize on every bolt when re-assembling the engine.

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