Chain tensioner bolt stuck- Any tips???

The nut on the chain tensioner bolt has one of the six sides stripped down. I've soaked it with liquid wrench for hours and it still won't budge. I need to tighten my chain but I can't loosen up the nuts and in turn the bolts on either side of the bike. I was thinking about cutting off the head of the bolt and getting a closed head six sided wrench around the nut but 1) it might not come loose and 2) if it does, i'll have nothing to grab onto but threads on the bolt. Then i'll be stuck with a bolt in the swingarm and no way to get it out. A friend of mine with an exc 400 ran into a similar problem with his bike. He was able to get the nut off, but the bolt was torqued so bad from pressure from the rear axle it had bent while it was in the swingarm. He had to get the bolt heated and removed and the swingarm hole re-threaded. Does anyone have any ideas, or suggestions about how I can solve this problem?????

'04 wr 450

Use some multigrips / pliers.

No easy solution.

I have one broken and other gets tight if not lubed occasionally.

Maybe heating, drilling through, lubing with bolt release lubricant?

On the broken bolt, I use long nut, so I can add bolt from other side, to ensure correct distance and it can also be adjusted.

Have not yet found any way to remove the broken nut.

Find a buddy with a torch and heat the nut up so its cherry red. It will come right off :crazy:

I remember reading somewhere that once your axle nut is re-torqued to tun the tensioner screw in one turn to get it away from the blocks and then tighten the jamb nut.

The reason was that once the axle is properly torqued it should not move. If its permitted to move against the tension screw it'll cause this problem.

It made sense to me...

A couple things I may try if the other suggestions do not work. Slip a openend wrench over the stripped nut and mig weld it on, loosen it up, you won't get much travel but enough to back out the tensioner screw. The nut ans wrench will come with it. Take the swing arm off first to avoid electrical damage the welder could cause.

Thanks for the help. I think I'll get a torch and heat that sucker up.

'04 WR 450

Get a penetrant product called "Free-All" available at NAPA stores and others. Soak the bolt threads two or three times over a couple of days. If this does not loosen the bolts, heat the area around the threads with a propane torch and gently rock the bolt back and forth. This has worked for me on several occasions, but does not ALWAYS work, I've had some that were a real bitch. If and when you get the problem resolved, put a dab of anti-seize on the bolt threads to prevent a reoccurance.

Not sure if this is feasible in your case, but a trick I often use to get really stuborn bolts off is to make a thin notch in one side of them with a dremil tool, then stick a punch or flat screwdriver in the notch and hit it around with a hammer. Kinda like a manual impact driver.

On that note I also commonly turn stripped phillips screws (mostly the brass ones on carbs) into flat screws with the dremil too.

Try "PB Blaster" from Pepe Boys, and a flare nut wrench

I am sure my 05 has a 12mm nut and a 10mm bolt head. If that is the case on yours simply use a deep 12pt socket to loosen the nut. It sounds like they need to be replaced anyway, so you might have to cut the head off the bolt to allow the socket to fit the nut. I use PB Blaster and it is amazing. I have used it on Axle U-bolts on Semi-Trucks and gotten them loose after a 1600lb gun would not budge them until being coated several times over several days. Normally they just torch them off. Also turn your adjusters half a turn back in after tightening your axle. They are not designed to hold the axle in place only assist in adjusting it. I would be careful about using a lot of heat around your aluminum swing arm. It can be done but be careful.

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