Quick (hopefully!) CV question from Aussie

[dt-911]

Hello there!

Hoping I am just doing something wrong... have managed to get axle nut off with only a i/2 socket and makeshift breaker bars.... but can not get any of the CV boot allen nuts to budge.

And it's the side (right) that isn't split, but doing both (as I should).

Any hints?

Dave & the Crusty Carrera

P.S. Have searched for hints but nothing specific so I am guessing that it's something i am doing wrong.

P.P.S. She is an 85 targa carrera 3.2 that fell in my lap ex. UK... which means a fair amount of salt has been in her life prior to being in my care.

[rosie82sc]

I recently removed the same from my SC, I used a 1/2 inch impact socket with about 1.5 metre breaker bar, they were still VERY tight even with that and actually cracked (as in releasing and not actually breaking) when they let go.

My drive shafts had been out about 2 years ago so I did not have a real problem with those bolts, a sharp hit on the back of the allen key when you are undoing a siezed bolt can often help. It would pay to use a good quality 1/2 inch drive allen key as it may be difficult to hit a standard allen key square on.

Rosie

[dt-911]

Thanks Rosie.

Sounds like I will have to invest in some tools...

I have been trying and re-trying with some long handled hex/allen key spanners (ones with long-ish handles) and standard little ones but nothing gets me decent leverage.

Bugger!

Ah well, it is getting cold now anyway.... kids are making pizza's, maybe I should call it a day.

Thanks again,

Dave & the Crusty Carrera

[KCinBR]

Remove the bolts with an 1/2 drive allen socket. You will need a very long extension so that you can work thru the wheel well opening, not under the car. The bolts should be tight, but not extremly difficult to get loose with the proper tools. Replace the bolts if you can, this is what the "experts" reccomend.

Good luck...

[Grady Clay]

Dave,
First, WELCOME to the Forum
You will find a lot of help here.



While you may ultimately need to cut off (Drimel, other) the bolt heads, using the correct tools and best process will give you the best chance.

Some ‘rust penetrant’ preparation will help.
Apply the penetrant to the exposed threaded ends of the CV joint bolts (on the backside of the flange).
Rotate the joint CW many times during this process while lightly tapping the flange radially.
Heat cycling may help but don’t get the parts too hot or you will need new CV joint grease, boot and transmission seal.



Here are the tools (or equivalents) necessary.
Make sure your Allen wrench (6 mm for M8 bolts or 8 mm for M10 bolts) is new or freshly ‘dressed’.
Make sure the hex opening in the fastener is absolutely clean and free of oil and debris.

This is best as a 2-person operation.
Jack-up and remove one wheel with the other three safely blocked both directions.
Don’t rely on your parking brake as you will need it for this operation.
Have the transmission in neutral.


Position the CV joint bolt you want to remove so you have a ‘straight shot’ with the Allen wrench and the long extension so the outboard end of the long extension rests on both the brake rotor and caliper.
(Don't bend the dust shield. Bend it back if you do.)
Apply the parking brake (if the brake won't hold, put a screwdriver in the brake rotor vent and against the caliper.)
Have your helper use the large (and long) open-end wrench to torque ‘load’ the impact tool to unscrew the fastener.
Your helper should not try and unscrew it, only forcefully load the tool system in the correct (CCW) direction.
Your helper should be prepared for a 'reaction' through the wrench.

With one hand on the impact tool, keep it (everything) forced into the fastener.
With the other hand, swing the hammer – hard.
With everything forcefully done, this can be a ‘one impact’ process.

After the impact, forcefully unscrew the bolt.
You will need lots of force to keep the wrench in the hex.
Go to whatever effort necessary to prevent ‘rounding out’ the hex in the bolt.

If you need more than one impact, rotate the axle 360º between each impact (to re-lube the bearing).

Practice your two ‘body positions’ as this is a ‘close contact’ two-person operation.
Don’t hit your (or mate’s) hand. You will need a powerful swing of the hammer.


Yes, you can get these bolts off.

While this thread does not directly answer your question, it is important for your reassembly.


Again, WELCOME

Best,
Grady

[QldChef]

dt-911, post your location, there are a lot of guys who will be willing to help if they live near you. I'm an amateur, but if your in Brissy i'm happy to lend some muscle if required. The guys on this board and in the Porsche community are are very welcoming and helpful, good luck!

[Targalid]

I don't know why these bolts are torqued on so tight. The factory manual gives a relatively low torque setting, usually 35 to 45 pounds, yet the axle bolts seem to be much more than that when I go to get them off. I used an electric impact wrench from Harbor Freight when nothing else would work. I don't know if these inexpensive tool stores exist in OZ but I know you can find a more expensive impact wrench at your local tool store. They sell here for $50 US. Electric or air impact wrenches are well worth the investment. You will use the tool for everything, from lug nuts to axle bolts.

[dt-911]

Thanks all,

I actually muscled 4 or 5 loose by hand with a reasonably long handled allen key but couldn't get a good angle on the last one or two so gave up and decided I would take her to a shop.

I then spent the first part of the day today on garden maintenance and plumbing for our bathroom reno. Had to go to the hardware for a plumbing fitting and stopped at their tool shop... thought I'd check pelican on my mobile and Grady's post came up... decided that with that amount of info I had better have another go! Aah and dummy me never thought to release the park brake and gear to nuetral and give the shaft a turn... I may even have been able to muscle out the remaining ones! Anyway, I spent the rest of the day hunting down and buying the suggested tools and will be onto it again tomorrow!!!

Was walking past her in the carport late in the day and got excited about getting into it again... damn these things are addictive!

Hoo-Roo, Dave & the Crusty Carrera.

P.S. How crucial are the suggested washers? Are they porsche only, or easily available at other (read cheaper) auto suppliers? I ask because mine appears to have the moon plates I read about somewhere and I thought they were safely re-usable.

[Grady Clay]

Dave,

Yes, you can re-use the ‘moon plate’ 2-hole washes.
Inspect them for damage or bent.
If yours are slightly rusty, I see nothing wrong with ‘cleaning them up’ on a piece of wet emery paper on plate glass.
Yes, you can install a new Schnorr washer on a ‘moon plate’ surface where you can see slight signs of a prior one.

The purpose of the 2-hole ‘moon plate’ washer is to provide an intermediate hardness piece between the very hard Schnorr washer teeth and the soft mild steel of the CV joint boot flange.
The 2-hole feature acts as a safety with one hole preventing the washer from turning under the other bolt (and vice versa).

New Schnorr washers are commonly available from industrial suppliers.
In the USA: Schnorr- A leading manufacturer of Belleville disc springs
A Google search for Melbourne came up with:
schnorr washers Melbourne, Australia - Google Search

Yes, many (most) feel it is critical to use NEW Schnorr washers every time the CV joint bolts are removed.
There are good technical arguments for keeping these new.

If your CV joint bolts have any rust (particularly on the shank or threads), replace them.
Be sure to use the proper class 12.9 bolts.



Some of the reasons CV joint bolts are hard to remove are:
The bolts are stressed very ‘tight’. The specified 33 ft-lbs for the M8 (and 66 ft-lbs for M10) are at the very high end for these class 12.9 fasteners.

The other reason is the exposure of the threads to the road environment.
The ends of the bolts protrude out the backside of the flange.
If these were ‘blind tapped holes’ in the flanges, there would not be corrosion issues.

The fact that they are hard to unscrew is actually good.
The 100 mm CV joints with M8 bolts were undersize for the service they see (Porsche changed back to the 108 mm CV joints with M10 bolts in about ’86).

Best,
Grady

[schumicat]

For the one that wouldn't budge, put a deep socket w/ 6" extension attached over the allen wrench and use it as an improvised breaker bar.

[dt-911]

Thanks for the replies and guidance with this query.

I tell you, not only has it made it much easier to do the job at hand, but with out the usual breakages and grazed knuckles. Having people out there that are prepared to put so much time and effort into detailing fixes for what effectively are complete strangers is both awe and confidence inspiring.

I even took the my laptop outside and now it's like having a coach in the shed with me and the Crusty Carrera!

Well that's enough guff, here's a funny incident that occurred... I got the axle nuts off with the 1/2 inch breaker and improvised extensions, then used my new tools (thanks again for advice Grady) to strong arm the inner cv hex nuts off (all in great condition but no washers). I then get the axles off and up on the bench ready to clean & reboot and guess what? Wrong boots!

Seems I misread the Pelican info and ordered the 100mm 85 carrera 915.69 versions instead of 108mm 85 carrera 915.73 ones.

Ah well, such is life, so I jump back on to Pelican Parts and order the right stuff (gonna do all 4 boots now too) and now I think I must have confused something again. I am pretty sure I read somewhere there is a need for gaskets but none of the parts diagrams include them for 85 Carrera or show locations except for one that shows one behind the inner most cover plate. But then I am certain I also read somewhere that nothing is supposed to be between those surfaces. So I have ordered 4 (as the site said are required) but am lost as to what to do with them when they get here.

Can someone please help with correct location of gaskets or whether I should just leave them out (FYI there were none anywhere on there that I could see).

Hoo-Roo, Dave

P.S. Found a local supplier for the schnorrs too! And it's not just the Mrs talking about her TV programs!

[dt-911]

Sorry, I sort of inadvertantly hid a question right at the end of previous post... this forum spins around so bloody fast it got buried real quick!

In essence the question is about CV gaskets... necessary and where?

Thanks again,

Hoo-Roo, Dave & the Crusty Carrera (85 targa 3.2)

[Grady Clay]

Dave,

Please post some images of your transmission axle flanges and the transmission side of your CV joints.
What size CV joints (100 mm with M8 bolts using a 6 mm Allen wrench or 108 mm with M10 bolts using an 8 mm Allen wrench)?
Is there a tin end cap on the CV joint?

Please also post images of your CV joint boots and tin boot covers.

Best,
Grady

[dt-911]

Hey Grady,

At this rate (saw your answer charge's) I am gonna end up giving the car to you to pay my bill!

It turns out I have 108mm which I believe means that I have a 915.73 version trans. Yes the inner ends have caps and when I popped one off there were no gaskets anywhere to be seen. Although 3 of 4 were in really good order and the split one (inner left side) was still well covered in grease (just pretty black).

Photo's are a bit hard at the moment as its 1am and I have to get off to bed soon to prep for a big day of daddy daycare with my 3 kids (G3, B5, B7) tomorrow!

I promise I will post photo's tomorrow though.

Thanks, Dave

[Grady Clay]

Dave,

Correct - no gaskets needed.
If the replacement metal boot covers are different thickness under the heads of the bolts, pay attention to the bolt length.
You should have 1½ (1-2) threads protruding through the flange.

You have the good set of big axles (that I need to do for my '79).

Yes - buisy day: "(G3, B5, B7) tomorrow!" Me also: B7 student.

2¢

Best,
Grady