MZ/MuZ Riders

OK - I'm taking apart my new Skorpion, and I've only run into one significant pitfall - the bolts that hold the rear of the tank are just spinning and not coming out! I understand from an earlier post that these are captive in the tank, and that at least one fix is to drill a screw into the side of the nut. But it seems like I can't do this until I remove the bracket!

Anyone had this problem and come up with a solution? I'm just about ready to grind the tops off the bolts to get the bracket off, but I thought I'd check for an easier way here first.

TIA,

Sam

first take off the bracket with the tank. Most people in fact take off the tank that way because the majority of the Skorpion tanks are broken like yours.
All three of mine were and lots of others I have seen.
Go out a get some sort of 2 component resin suitable for thermoplastics - not epoxy or polyester. Over here in Germany, one is available from Würth and colloquially called faring adhesive, because that is what it is mostly used for. It is black and sets in about 5 minutes.
After emptying the tank, turn it over and carefully drill from underneath with a 1/8" twist drill slightly to one side of the captive nut. If you are lucky, you will be able to jamb that nut with the drill or a piece of rod enuf to get the bolt out. Once you have the bolt out, enlarge your drilled hole, being careful NOT to drill thru into the actual tank. Put vaseline on a new M6 bolt and turn it into the captive nut. Now get that gunk you bought and inject it into the drilled hole, turning the capive nut as much as possible the first minute or so. Inject as much and as firmly as possible. If you have air, blow into the hole after the first injection and add more gunk. Remember, most of these repair resins set very quickly so this manipulation should be done within 2 minutes or so. before it is too late back the greased bolt out and back in a couple of times. remove it just in time. Let the whole thing set long enuf and you're done. You may have to clean out the threads with a M6 tap. Filing a groove in an M6 screw is tap enuf for this purpose.
I have fixed a number of tanks this way.
The bolts get stuck because dimwits put Locktite on the bolts after they lost the first one(s). I secure the two bolts with wire in the classic manner. that way I don't even have to tighten them.
On the racers, I do not bolt the tank at all.

I think you can see the rubber strap bolted to the tank and hooked on to a allenhead bolt fixing the bracket. Of course, the two two parts of the bracket holding the rubber grommets have to be sawn as to a height just slightly higher than the rubber part the tank rests on, just high enuf to keep that center nose of the tank in position.

Thanks for the real good description. But appears to me that the only way I can drill into the captive nut is by drilling through the bracket! Or, is the nut much deeper in the tank than I would think? Or do I have to drill in at a sharp angle?

I really like your rubber strap idea. Thanks for the pic.


Sam

it should be possible to pull the bracket to the side enuf to drill, due to the rubber grommets. The captive nuts are between the inner and outer tanks, recessed about 5mm.

Whoops. I drilled in right behind the bracket into the nut and a) snapped the drill off in the nut and b) the nut still spun! Furthermore, it appears that I now have a hole in my gas tank. I gave up and did it the hard way; I ground the tops off of the two bolts and from there it wasn't hard to get the bolt bodies out.

I'm not sure how I could have possibly not gone into the gas tank. Bill - you speak of an inner tank, are sure all of these have an inner/outer tank? I widened the holes to 6mm so I could see what was going on and I seem to be looking into the tank proper.Regardless, I''m confident I can fill the holes with methacrylate and a plug.

Sam

So - this is what I ended up doing. First, I ground the bolt heads off. Once the bracket was removed, it was rather easy to loosen and remove what was left of the old bolts. I then made a small puller out of a socket, a washer, and a screw and used this to remove the inserts. From there, I cleaned the holes out with a Dremel. The next step will be to reinstall the nuts, holding them in with lots of methacrylate (fairing glue) They will never go anywhere again, I'm sure. A bit of work, but I know it's fixed now.
I'll take another shot when I'm done.

Sam

Argh! Piccy-piccies no work-worky!

Linegeist wrote:Argh! Piccy-piccies no work-worky!

Whoops..should work now!