2003 FLSTF. The nut holding my dash on the tank won't come off because apparently the square neck of my carriage bolt has rounded out and just turns when I try to turn the nut. I have put great upward pressure on the nut while slowly turning, which is the only reason I got it to move in the first place, but it's only a scant 1/8" loose. Not enough to reach under and somehow grab the bolt, but just enough to rattle way too much if ridden. It will loosen no more. Any suggestions?

 

Drill into top of bolt. See if can turn nut while holding drill bit. Drilling while holding the nut may turn the nut off for you. If not use self tapping screw in drilled out hole to hold bolt while turning nut.

Or depending on clearance, use a small roto zip cut off wheel on nut.

Of course control your metal shaving with vacuum-compressed air.

 

Also dab nut with PB every now and then for 24 hrs before attempting.
Control sparks, hot metal, around gas tank of course.

 

I'd just be done with it, tape off the console and carefully cut the bolt right under the nut and replace the whole shebang.

 

It would have to be through the nut, which seems to have become one with the bolt. Or are you saying sort of do a counter sink thing where I drill bigger into the nut, then smaller into the bolt?
To complicate things this is a custom nut with an allen head, from a Kuryakyn dash cover so this nut reaches down through the cover to screw onto the stock carriage bolt. Unfortunately they won't sell me just the nut, but really considering ruining the nut to get it off then replacing the carriage bolt, if I can find one. Unless it's the tank receptacle that has rounded. Then.........
sorry, way too wordy

 

I have a custom dash cover, so the bolt doesn't stick up enough to cut it off.

 

That sucks... could you get a nut splitter on it? The next option would be to either try the countersink option above or just start cutting/grinding off the nut bit by bit until it breaks loose.

 

just thinking about that "countersink" thing. I don't think that would work very well because the 'nut' is a round allen head 'nut' that resembles an allen head screw, so round. So no way really, to grab that nut while trying to turn the bolt with the drill bit in it. And it's a 1/4" allen wrench so the bigger drill bit would have to be a bit smaller than that if I wanted to preserve the allen part.
Geez. I'm thinking too much. I'll keep you updated as I go along

 

Easy enough to get spun-up in overthinking when the seemingly simple things go sideways.

 

You describe an allen that attaches to a bolt, so this is an after market attachment like a button.
Can you pull console UP but also to towards REAR tire with one hand and at the same time try to turn allen with other hand?