Mrmerlin

most of the bolts on your car are hi quality carbon steel bolts with a cad or zinc coating hence the color either silver or yellow/gold.
Depending on how your heating the metal your working I suggest to use a Mapp gas torch its the one in the yellow canister,
it gets hot faster so less surrounding parts are damaged from heating .

Use common sense when heating a bolt so you dont damage surrounding metals or plastics

MainePorsche

Stan,
Thanks.
I have a good little torch for the task. How long after heating to re-attempt though ?

MainePorsche

Frustrating day with the caliper bolt issue. Found I didn't even need to deal with them to get the Brembos off. The two short 19 mm bolts that brace the caliper were all that were needed to remove them. What a large waste of time. Live and learn... Anyway the rear suspension is now ready to be dropped. This will be on next working day. The transmission arrives from Greg tomorrow AM.

69gaugeman

Stainless can be used where ever there is no stress on the assembly (belly pans, oil pans, covers, etc). Stainless bolts have about 70% of the tensile strength of carbon steel bolts. They stretch easily. Any where there is stress (suspension, brakes, etc) always use grade 10.9 or better

Carbon steel plated bolts for suspension and brake per the above

Heating a bolt to remove when locktite is in just needs to be 265 Deg F

They use locktite from the factory. A removable blue one. These bolts are subject to forces and vibration and must be high quality bolt of a carbon steel variety.

Lizard928

I am almost nervous to ask this question.

What bolts are you undoing????

The rear calipers are held on by a larger bolt (M14x1.5 iirc), and have a 19mm regular hex head on them.
The caliper does have a couple of allen head bolts that go through it, which I believe use an 8mm allen key to undo. If you have undone these, your problems have increased........

MainePorsche

Thanks very much for that information.
There is a great shop up here specifically for hardware for the various contractors and others in this rural area. I have the ability to choose well.
On the caliper bolts removed at looks as though there was RED Loctite used. I've never had so much trouble removing hardware before on all the work I've done. I really lost a lot of time and completely snapped two 10 mm 3/8 in hex sockets.

MainePorsche

Colin (if I may),
I did remove two of the four allen head bolts before seeing the error of my way.

Mrmerlin

wait what? ^^^^

if you post some pictures you will get better advice,
this might be something for you to consider

Fogey1

For the record, some previous threads on Penetrating Oils. Many swear by a 50/50 acetone/ATF mix.

https://rennlist.com/forums/928-foru...ating-oil.html Wally 2008

https://rennlist.com/forums/928-foru...ating-oil.html Glen L 2012

https://rennlist.com/forums/928-foru...teresting.html Jim M 2012

Landseer

Why are you removing the brakes?
Let them stay attached.
Undo the flex hydraulic hoses at the body.

Undo E-brake line at handle.

Crossmember comes out with brakes, shocks, springs, all as a unit.

Even axles can stay attached at hubs, too if you want.

MainePorsche

Have the calipers suspended. Was going to leave brake line to the body. Was going drop lower control arm from the body - not detach thru eccentric.
Mis-planned regarding removing calipers before detaching axles from the differential. Will correct this. Once rear suspension/crossmember cleared, was going to take transmission down as a detached/separate unit.

Lizard928

I'm more of an advocate of the suspending the brake calipers from the body too. But I do recommend pulling the e-brake cable out of the cabin.

And as to the calipers, I am afraid that you have opened yourself up to a world of trouble if you did that.....
Those bolts are not regular hardware store stuff, and are interesting to get right again......

ammonman

While you have the crossmember and trans down is an ideal time to renew the rear sway bar mount rubber. It is also a great time to clean and break loose (then re-tighten) the rubber brake hose to hard line connection as you don't get much better access than now. makes a future brake hose swap MUCH easier.

Mike

MainePorsche

Colin,
Specifics on the bold type issue(s) so I can put right.
I was thinking of a brake job I did recently on another one of my vehicles, and was so wrapped up with the order of operations of this job which is new to me, I didn't take the appropriate steps with the caliper removal issue - don't ask me what I was thinking for it was offline. Hopefully will not be so irrevocable to make right.
Thanks,
Craig

MainePorsche

Thanks Mike.
Already making a list things to do while I'm in there, and will add this.