Stripped treads on rear bolt to gas tank

[pquinnphd]

2009 Ducati M1100. 
I did not notice the problem until I tried to get the tank off for a project.  Taking the tank off should have been a snap.  We need to do that just about everything, including getting to the battery.  The design seems weak.  I had to Dremel the head of the bold off.  Has anyone else had a similar problem?  What was your solution?  I have not put the tank back on because I'm still working on the project.  But I was thinking of leaving the bolt in place (since I can't seem to remove it) then I can just stick it down in the hole it goes into and add something else to hold the tail of the tank in place or down.  Any thoughts?

[teddy037.3]

is the bolt stripped? or the threaded hole?

:edit: wait... so the bolt is stuck... in the frame of the bike? have you tried removing the bolt's body? how do you know it's stripped if it's still on the bike?

[elgallo73]

It WOULD HAVE been much easier to fix this without cutting the head of the bolt off!  There is a procedure which in your case is now irrelevant.

Your best bet at this point would be to dremel the plastic around the bolt enough to remove the insert.  After removing the insert, a 13mm crescent wrench will fit the square nicely and coupled with a set of vise grips, you should have no problem removing the bolt.

Clean up the hole in the tank where the insert used to go and using sandpaper, rough up the sides of the insert.  Mix up some JB weld and daub a fair amount into the hole you just cleaned up.  Place your insert in the hole and clean up the excess.  If you let it set overnight you should be good to go.

For the record, I had to do this with my 2011 Monster 696 (although I used a drill/allen bit and tire spoon to separate the tank from the insert.  For some reason, Ducati assumed that red loctite was the way to go in this application...

[elgallo73]

By the way, the new tank bolt is $11.99!!!!!

[teddy037.3]

For some reason, Ducati assumed that red loctite was the way to go in this application...

if all it is is red locktite, that's not so bad... hit it with some hot air to warm it up and it'll break loose

[elgallo73]

hit it with some hot air to warm it up and it'll break loose

I am assuming with a heat gun???  Not a good idea, for several reasons:

     - The insert will function as a heat sink, likely melting surrounding plastic
     - If the tank is still installed, the heat WILL damage the rubber pad between the tank and screw

One more note, during reassembly I do recommend blue loctite given the bolt location...

[teddy037.3]

it's thd'd into plastic? that's pretty lame...

although, I can't imagine the plastic having a melting point so low that it'll get make the beast with two backsed up before you can break the locktite


:edit: is it the screw that comes up from the bottom? 779.1.5432B? can you see the insert looking down from the top side of the tank? it looks like a through hole on the parts diagram

[elgallo73]

The insert is not threaded into the plastic, but is a square piece (no through hole) 13mmx13mm and approximately 14mm deep (don't quote me on that).  When I repaired mine, it appeared to be made of stainless steel.  Using a heat gun is likely a reasonable method to separate a bolt and nut with red loctite provided the melting point of any adjacent materials is relatively high.

You can choose whichever method you want, but I personally would not use a heat gun for this repair owing to the fact that you will be heating up your tank, possibly to the point of damaging it.  Given the cost of a new tank, you may wish to reconsider.

Removing the insert is SIMPLE.  Use a dremel tool or similar to remove some of the plastic around the bolt.  With a little work, you should be able to see the insert.

Or, you could take a drill and tighten the chuck around the exposed bolt shaft.  Use a pair of pliers with the key to tighten the chuck as tight as you can get it.  Then, start the drill.  Ideally, the insert will be spinning around inside the plastic, heating it.  Then attempt to extract the insert by pulling on the drill.

Here is a (horrible) graphic to illustrate:

         |  |
         |  |  -> bolt shaft
         |  |
-------------------   -> tank surface
     ---    ---
     |          |
     |          |  -> insert
     ---------

Your goal is to either:

(a) Spin the insert in the plastic fast enough with a drill so that it can be pulled out (will melt a minute amount of plastic)

or

(b) Cut enough plastic around the base of the bolt shaft to expose the insert and thus facilitate removal

Let us know how it goes!

One more note regarding the heat gun method:  with your current situation, the insert is still in the tank, thus, the only portion you could potentially heat would be the bolt shaft.  The bolt shaft could be heated (and of course, so would the rear of your tank, potentially melting various portions of it), but here is the issue, while the bolt shaft might heat up, the insert will do so at a much slower rate.  The bolt shaft will expand while the size of the insert will remain relatively constant, thus effectively seizing the bolt even more.  Keep it simple, if you use either of the two methods I just described you should have no problem removing the insert!!!

And in answer to your query at the end of your post, you will NOT be able to see the insert from inside the tank (through the filler hole).  The portion of the tank in which the insert is installed (what I will refer to as the "tang") is not exposed to gasoline for at least 1 or 2 inches from the insert towards the front of the tank.  I believe you have the part number correct.  Your dealer should have this part, or at least AMS Ducati in Dallas does, not sure about your area.

[teddy037.3]

And in answer to your query at the end of your post, you will NOT be able to see the insert from inside the tank (through the filler hole).

I think we're talking about different parts of the tank...
http://issuu.com/ducatiomaha/docs/mo_1100_usa_2009_ed00_r002?viewMode=magazine&mode=embed

sheet 35 shows a screw (pc.7) that installs upward through what looks like a portion of the frame, a pad, and then a through hole in the gas tank.

I thought this was what OP was refering to... the "rear bolt to gas tank"

:edit: blarg. thanks be to youtube... idk why ducati put that on the drawing if the damn thing is blind  


OP, just brute force the screw out and replace it with another one 

[elgallo73]

Teddy,

The part you are referring to (sheet #35, part #7) is exactly the part I had to remove and replace.  The OP could drill right through and install a bushing, of course he will still have a problem with the insert, which should be removed if he attempts this.

I had thought about leaving the insert out, installing a bushing with epoxy as filler for the space evacuated by the insert and running a bolt through the whole thing, but decided against it when I realized how easy it would be to fix.

[teddy037.3]

yeah, I realized that when I watched a youtube video on tank removal... the hole is blind on the actual tank... ducati's drawings always showed a through hole, which was why I was confused over what you were describing.

stupid ducati

[alibaba]

Just for kicks, I wonder how essential this bolt is.  There is one side bolt ataching the tank to the frame.  Maybe the front of the seat holds it down also - I would have to check.  But on my '09 M696, even when all the attachments are done, I need a very large screwdriver to pry up the rear of the tank for withdrawal and removal.

Is this bolt superfluous considering the agravation? Comments?

[Raux]

seeing that your seat is hooked at the front to the tank. and going over a bump would allow the tank to rise, messing with the seat/tank union... ahhh no I would not leave it unbolted at the rear of the tank.

[DucNJ]

I just discovered this yesterday while trying to install my new termi ket on my 2012 Evo. My plan as of right now is to take it to the shop and have them discover it. Would this be covered under warranty?

Has anyone experienced this issue since this was started? I am furious!!!!

[oldndumb]

Search is your friend. You will find that rear attach point spinning insert is a goodwill tank replacement for your bike, not to be confused with a recall.