Dos & don’ts - getting CV Joint bolts out

[PopsRacer]

I’m replacing the rear wheel bearings and axles on my 88 carrera. The 6 bolts that hold the inner CV joint to the transmission flange are really stuck. Since the flange is AL(?) I don’t want to hurt it.
I’ve read lots of ‘replace your CV joints” and “remove your stripped CV Joint Bolt” threads - but what are the good options for getting the bolts started?

* I have soaked them in penetrating oil for a full day so far and heated one up to cherry red a few times (heat, oil, wrench, repeat) but I have gotten nowhere so far.
* I did clean out the inside of it and made sure my 8mm hex key is good
* I have tried both hand and electric impact tools so far.

My guess is that heating the head of the bolt isn’t doing much since the threads are pretty far away. What is safe for the flange end of the bolts? TIA

[75 911s]

The transaxle flange is steel. Try to hit the backside of the thread with penetrating oil in between the flange and the trans.

Smack the head of each bolt straight on (lightly) with a flat hammer to break the rust loose.

Heat the flange a bit to make it bigger and then use an air impact. Make sure you are fully seated with the bit as you said. Wurth makes a cooling product that you can make the bolt smaller, or you could use carb cleaner. Not sure if that might make it brittle though.

Can also use a long breaker bar. That's what I usually use. Make sure your ebrake is on.

[88911coupe]

Clean inside the hole for the hex wrench thoroughly, mine had a LOT of grease and dirt so the wrench started to slip. Cleaning it gave more grip. Also use a GOOD wrench. I initially used one of my cheap hex's and they started to deform.

[pmax]

Might be time to break out the Q-tips !

[Dave Colangelo]

Heating the head of the bolt wont do much but soften it, its the flange you want to expand a bit to allow the threads to come out easier, try heating from the backside. Id stay away from impact tools on this and stick to PB Blaster/Kroil paired with a breaker bar instead with smooth force applied, the allen bolts are just a bit to prone to stripping for an impact tool to be the right thing here. The thread holes come out the back of the flange so you can also spray the PB-Blaster from the backside and get it in there. Tapping with a flat hammer can help break light rust and seizing when needed.

The flange (on both sides) is steel.

Regards
Dave

[PeteKz]

Try a hand-held impact driver. When you hit the driver with a hammer, it pushes the bolt inward, as well as twisting it. I've got things loose with impact drivers that I could not otherwise loosen.

[wazzz]

I went through this a couple of years ago when replacing CV and boots on my 88. Engine and trans have never been dropped on my car, so these bolts seemed to have never been removed since factory.
What worked for me was my air impact gun. At first bolts wouldn't budge, so I raised air pressure past the impact gun spec on my compressor and all bolts finally came. They are Class 12.9 steel bolts so they are pretty strong. Can't remember what is the max torque delivered by my impact gun, but it is pretty high.

[PopsRacer]

Thanks! ok, so I have been doing this backwards.. (heating the wrong end) that tracks. . Glad the flange is steel, and in hindsight it makes a lot more sense. I will try the hand impact tool as well, good idea. These things are only supposed to have 60 ft lbs on them, I was thinking a bit of shaking up might be the trick but I don’t want to hurt the transmission (hitting that flange with a hammer). I can’t believe how tight they seem to be. @Wazzz - that’s exactly the case here.. '88, engine has never been out as far as I can tell.

[PopsRacer]

Cleaned them all with a q-tip and brake cleaner, then a little heat on the flange with a MAP torch, a quick spray of PBlaster and off they came. One was still a little stiff, but I didn’t need anything but a regular wratchet for any of them. Much more like it!

Tapped the hub out cleanly with the smallest disk in the HF aluminum bearing kit, and now just need to make the bearing press so I can remove the old one. The new one is in the freezer thinking small thoughts.

[wazzz]

I need to change rear bearings too so I'll watch this. Please take pictures of puller and press and anything useful for someone who has never replaced rear bearings. Thanks!

[A930Rocket]

Are 12 point bolts available instead of the hex bolts?

Seems like that would make stripping out the bolt head less likely.

[Locker537]

Success.

I'm a fan of homemade tools, but Astro Pneumatic makes a very nice kit to remove and press wheel bearings with the arms still on the car.

It's currently $100 on Amazon too...

https://www.astrotools.com/product/master-front-wheel-drive-bearing-adapter-kit/

There's even an updated version that I did not know about...

https://www.astrotools.com/product/heavy-duty-grade-9-master-fwd-bearing-adapter-w-thrust-bearing/

[pmax]

Q tips are a staple.

[PopsRacer]

the homemade one didn’t save me much money and I had to special order the 3” close nipple (the plumbing equivalent of the electrical conduit bit) so I basically wound up buying that same bearing press kit. it worked great for removing the bearing from the trailing arm.
For getting the outer race off of the hub I used a cheap bearing puller from harbor freight and a straight arm puller (just needed 2 arms) the key thing in my case was that the axle nut washer is exactly the right size (and quite thick) so I used that to hold the tool I drove the bhub out with and then inside that went a centering tool from a press kit so i had something to pull against.

The opening had a bit of rust in and around it. I cleaned it carefully with a brass brush and then 1200 grit, then polished.





After the cleanup:


What the stack looked like to pull off the race. Really glad that washer fit perfectly.


‘exploded view’

[PopsRacer]

Question:
Im assuming we should use a bit of bearing grease on the axle splines, but do we use any oil etc on any other surface to aid with re-assembly?
From reading posts and watching videos it looks like the other pieces (bearing, hub) get pressed in dry but i thought it best to check.

[David Inc.]

Originally Posted by A930Rocket

Are 12 point bolts available instead of the hex bolts?

Seems like that would make stripping out the bolt head less likely.

Pelican has them in the M8x45 bolt, and yeah they're so much better. I don't know if they have them in the M8x50. Only $1.24 each, too, so not bad at all.

https://www.pelicanparts.com/More_Info/PAF107190.htm?pn=PAF-107-190-OEM&bc=c&SVSVSI=0574

[OsoMoore]

Originally Posted by David Inc.

Pelican has them in the M8x45 bolt, and yeah they're so much better. I don't know if they have them in the M8x50. Only $1.24 each, too, so not bad at all.

https://www.pelicanparts.com/More_Info/PAF107190.htm?pn=PAF-107-190-OEM&bc=c&SVSVSI=0574

Can we lose the 5mm of length and still get a proper hold? These things torque pretty tight. I guess one could order them on McMaster Carr, but I worry about getting the proper metal hardness etc.

[Locker537]

You pick the hardware specs on McMaster and Belmetric. You can order them by the box full...

[David Inc.]

Originally Posted by OsoMoore

Can we lose the 5mm of length and still get a proper hold? These things torque pretty tight. I guess one could order them on McMaster Carr, but I worry about getting the proper metal hardness etc.

I don't see that McMaster or Belmetric sell internal triple square bolts. To be honest I don't know who the heck does outside of OEMs as I only ever see them sold in VAG car applications.

Might be able to call up Pelican and see if they stock M8x50 for a different use case?

[A930Rocket]

I could not find the internal triple square bolts on either site myself.

What is the thread pitch?

Would an external triple square fit? M8x50. 12.9 with 1.25 pitch.

https://belmetric.com/12-point-flange-bolt-12-9-black-m8x1-25-coarse/