Wow Pete, I'll stop feeling sorry for myself after seeing your 'Broken Bolt Nightmare'!

Stripper Steve (sic) - The numerous applications of penetrating oil didn't seem to help. Heated block and frozen bolt (shout out to Bruce for the canned air suggestion as it REALLY WORKS), made some progress but I had to stop because of arm and shoulder fatigue. This working under a car on jack stands is a giant PIA.

 

I noticed your working conditions. Kudos to you for hanging in there. Stay safe!!!

 

As your Porsche mechanic suggested, apply gentle heat to the case, not the bolt. Someone may have used lock-tight on the bolt and it needs to be melted. Try tightening it just a little and then loosening again. Keep up this pattern of tighten/loosen. Lock-tight company makes a product that will freeze a bolt just by spraying it on, we used to use it when I worked as a Millwright. You might find it at an industrial supply/fastener store. Heat the case and spry the bolt. It may just be corrosion between the metal bolt and aluminum case. Good luck!!!

 

I'm not there to look but if this is a through hole and threads protrude on the other side wire brush those threads so you don't pull dirt (and perhaps damaged threads) into the block as you remove the bolt.

 

Throughout my years of Porsche ownership I've always done cosmetic type work on my cars but have always used Indy mechanic for mechanical repairs.
I did replace the oil sender on my 964 which required removal of engine parts and it was the last time I tackled a mechanical job. Always worried about fvcking something up.
Whats strange is I do all of my own plumbing and electrical work/repairs on our properties & rental properties and some of those jobs have been intensive/difficult but I don't have the same paranoia as working on Porsche.
I understand many owners don't have Indy shops close by and I've been fortunate to have my 35 year Indy Porsche mechanic 5 blocks away.
I applaud all of you guys that work on your cars. Nice to save the $labor costs and must be satisfying as hell tackling the repair.

 

I like his reviews as they are purely data driven, easy to navigate and gets to the point. He's tested everything from shop vacs to adjustable crescent wrenches.

 

SUCCESS WAS FINALLY ACHIEVED!!!! Thanks to all of you for your suggestions and positive comments.

After trying various combinations of penetration oil, opposing 1/4 turns, heating the block, cooling the bolt, more penetrating oil, drive the bolt all the way back in and all the back to stuck, I decided to get medieval on it's ***. I went to Lowes and bought a 20" piece of 3/4" pipe for my current ratchet, an extended-length 1/2" drive ratchet with 72 teeth, more propane, and more canned air.



I went home and cooled the bolt, heated the block and cooled the bolt again; I mean frost was on that thing!



Still it was a struggle to move the bolt. I tried various tools including my 3/4" drive breakover bar. I got best results from my existing standard ratchet with the pipe extension on it. I was only able to ratchet one tooth at a time but after 90 minutes of working it, I got that sucker out. Would you believe that it stayed tight until the very last turn! Here are some photos of the bolt. Using strong light and my best reading glasses I conclude that the last ~3/4" of threads are full of smeared aluminum which I assume are the threads from the bolt hole in the block.

So my next adventure will be addressing that hole but I'm unsure of the proper approach to fixing it. Drill it out and use an insert? Drill it out one size up, tap the block bolt hole and use a new, larger bolt? Suggestions?









Thanks again for all of your input. You guys are great!

Scott

 

Wow. Was the trans ever off the car before? Perhaps it was reassembled with the wrong bolt in that position?

 

I have been following this thread with interest. Congrats on getting the bolt out.
I think that Wayne Smith was onto something when he suggested checking to see if the offending bolt was in a "through hole", and maybe it should be cleaned.
From the pictures that you provided of the extracted bolt it appears that the end of the bolt is corroded. The deposited aluminum in the threads is likely the old threads ground out by the coarse iron oxide layer. This kind of corrosion does not occur within the shaft of the threaded hole. I suspect that during a previous repair the wrong length of bolt was used, and it extended too far beyond the shaft and was subject to the elements.
So if Wayne and I are correct, then you should verify the correct length of bolt to put back into this position.

 

Does that mean that bolts been removed before and some non qualified guy going real hard with an impact in a previous life is the cause? Man that's a shame. Glad you got it out.

 

Time sert is the way go if you can get a drill on it.

 

Saaboteur - I don't know if the transaxle was out before since I bought the car from a broker and it had no documentation. Other than this issue, it has been an awesome 997 (my second 997).

DbruceJ and Wayne - the end of the bolt hole was open but the bolt did not extend beyond flush. As such, I conclude that it was the correct length bolt. That being said, corrosion could have initiated at the bolt-end hole. The underside is pretty clean with no abnormal corrosion so I don't think that it previously lived in a high salt environment (north or near the sea).

Chalkboss - Your post said 'timesheet' but did you mean timecert and got dorked by autocorrect? Yes, I'll be able to get a drill on it. I don't have a 90 degree drill like the one Pete showed in his pics above but I'm pretty sure that I can get a conventional drill in there normal to the hole. I'm not looking forward to that process. I'll work to drop the transaxle tomorrow then I'm off Friday through Sunday for a fun weekend at Amelia Island.

I'm recently retired so I definitely miss having a team of engineers that I can lean on to research, analyze and determine the best solution and the process to implement that solution (customer products only, not my 997, he he hee).

Regards,

Scott

 

Are you going to try and retap that hole? What’s the game plan.

i would try with the original size and retap. Put some washers in there, new bolt see if it’ll hold spec. If yes gold, if not helicoil it.

 

Well, the important bit is that the bolt is out now. And you'll be able to insert the proper one for sure this time. Will be interested to see your comparison of the bolt lengths when you get a new one.

 

OP- how many of the other transaxle bolts were loose/removed when you attempted this troublesome bolt?