Rear trailing arm broken bolts, How in trouble am I?? Options

[PaIsa]

Long story short, 2 of the 3 bolts holding the left rear trailing arm broke on me. One broke and left some of the bolt out of the hole so I thought I could get it with heat and vise grip but nope. She is stuck. The other one broke and what is left is in the hole.

I cannot believe I am the first 914 owner dealing with this.

As I said, for the bolt that left me something to work with my plan was to heat it and use vise grip to try to get it. Tried on multiple occasion but she does not want to come out.

For the other one I guess I only have left to dril it out and try to redo the threads hoping for the best.

Does anyone has any other advice or method to try.

I do not have a welding machine so welding a nut is not an option for now and not sure it would work (for the one that sticks out of the hole).

I am open for any advice. I plan to work on this with my son this weekend.

Thanks

[914werke]

One thing that I am unsure of is the fact that these 2 ''bobins'' are open from bottom to top.

Depends on the MY of the car. Early cars DID in fact use caps, later cars the holes at top were either welded or brazed closed. (IMG:style_emoticons/default/idea.gif)

[PaIsa]

One thing that I am unsure of is the fact that these 2 ''bobins'' are open from bottom to top.

Depends on the MY of the car. Early cars DID in fact use caps, later cars the holes at top were either welded or brazed closed. (IMG:style_emoticons/default/idea.gif)

Mine seem to be capped like 1/2 to 3/4'' from the top. As I said, not a big problem as if needed, I could drill through.

In the case the thread get trashed, does going to a larger bolt could be an option. The sleeve (bobbin) seems beefy enough to accept a larger bolt. I guess it would mean increasing the size of hte holes on the trailing arm console. Does anyone see any problem to this last resort option, before having to replace the sleeves. One other option I see would be to have long bolts going thought the sleeve and putting a nut on top of the sleeve.

[Superhawk996]

Mine seem to be capped like 1/2 to 3/4'' from the top. As I said, not a big problem as if needed, I could drill through.

My bet is the caps were removed / lost and the holes at top left open. Dirt and corrosion then sits on top of the bolt forming a plug. I’ve seen that before.

Again, start soaking with penetrating oil, pimp juice or whatever. Fill the hole - let it sit. Rinse lather repeat. Do this for days in advance.

Then see if you can begin to remove it - break it - drill it - chisel it once it softens up.

The other less likely option is someone broke the bolt in there previously and left it. Maybe was only grabbing a few of the lower remaining threads with a new bolt threaded in below the broken portion. (IMG:style_emoticons/default/confused24.gif)

As always - start least destructive and work your way to more aggressive methods. Do Not use an EZ out - once that hardened piece of tool steel breaks in a bobbin you’re absolutely screwed with EDM being the only method to remove hardened tool steel. And by the way - practically impossible to EDM on vehicle; even harder to EDM on car and upside down. Don’t reach for the EZ out, just don’t.