jreifler

Requisite disclaimer: I promise I have read every post I could find here and elsewhere, and watched every video on the internet, and yet . . .

Cannot budge LF centerlock. RF came loose with roughly the appropriate amount of force applied.

Just to make sure I wasn't going insane (or had become even weaker than I imagined), I even tried loosening the LF with the torque wrench on (as opposed to breaker), set to its max 600 ft/lb, and got nothing. No movement.

Am I missing something? Is it possible that the LF lock is not actually engaging? The socket was completely flush on both sides . . . Wheels were on the ground with blocks and brakes applied. Using the proper socket, and Precision Instruments breaker / wrench combo.

Did not jack the car, as my intent was not to remove the wheels, but merely to swap out faded red / non-matching centerlocks for black.

Would greatly appreciate any advice or ideas.

Thanks!

8Lug

Sounds like you're doing everything right but the center lock may have been overtightened and simply requires more force. How about trying a torque multiplier?

FLT6SPD

Check plunger, "C" below fro free movement and that is fully depressed when loosening the cl

jreifler

If by "torque multiplier" you mean me and another guy fruitlessly putting our weight on a lead pipe attached to the end of the breaker bar, that has been done . . .

jreifler

So, will definitely check again to ensure it moves freely, but how am I to test whether or not the lock is engaged / depressed with the socket fully on ?

8Lug

Ha!. Not quite. I mean one of these:


You can get 1100 ft/lbs of output force on this by applying only 365 ft lbs of input force.

jreifler

Ah. Yes. That looks less absurd. Will explore this route, assuming that extender will work with the Precision wrench.

8Lug

The input on this is 1/2" and the output is 3/4". Your precision wrench is 3/4 so you would need a reducing adapter in between. The "arm" you see extending on this device rests against the floor. It keeps the device from spinning in the opposite direction of the force being applied.

You would need this:

https://www.homedepot.com/p/TEKTON-3...7823/207096676

jreifler

I see. Thank you. I have a set of impact-grade adapters, so that's no problem.

JB911

There's a very long thread about Renntorq, a tool created to remove the center lock nuts. It is expensive, around $2200(!)
https://rennlist.com/forums/991-gt3-...ations-19.html

But if you read towards the end of the thread, post #282, a user with a dry CL broke the thing and had to use a long breaker bar instead. People that do no maintenance and cleaning/re-greasing with the required Optimol paste will end up in this situation. You can not loosen or tighten CLs with the wheel touching the ground. I've pointed out older youtube videos with shops and people "cracking it loose" on the ground, doing damage.
You can get the Optimol paste at a BMW dealer for a fraction of the price, and the new name is Molub-Alloy Paste, still made in Germany by Castrol. If you look at your CL nuts after some time the paste gets hardened by heat. Disassembling, cleaning and re-lubricating is a chore-use gloves, and directions on how to do it are available-

Only at the end of that long thread was this point made, and if people have been using it without re-lubricating the nuts it's kind of a meat grinder that can destroy the nuts and the wheel surface.
Hope you can get the nut out.
If you have a long breaker bar and it's still not enough, try buying a 6' long pipe at a hardware, slip it into the end of breaker bar. I would even caution to have someone pushing the tool flush against the CL to make sure it doesn't slip off and damage the CL surface/teeth. That would be disastrous.

jreifler

Noted in a post above that we tried the pipe extension. My current theory is that the centerlock itself is not fully depressing on the LF for some reason. Going to re-check that when I can get in the garage this week.

I have the appropriate paste and already prepped the new centerlocks with it.

Auto_Werks 3.6

I was most confused in the initial post where he said he wasn't jacking the car. The car needs to be supported on stands and someone or something needs to keep the brakes applied.

I do the lube maintenance on my CL parts, but even when maintained they are harder to remove than they are to install. There is usually some amount of jumping on the end of the breaker bar. I've lost about 40 lbs this year. When I was 230 I had no trouble removing the nuts... at 190 there is a lot more struggle.

jreifler

I had the brakes applied, but wasn't jacking the car because (1) I didn't know that was a required step; and (2) I was only removing the centerlocks to replace them, and have no other need to remove the wheels.

It's no problem for me to get the car in the air, but just for my edification, why can't the wheels be on the ground for this? Will that actually prevent the locks from disengaging ?

Thanks again to all for the education!

JB911

Instructions specifically say to have wheels off the ground when loosening and tightening the CLs-
They also instruct the owner to inspect wheel surfaces and CL cones for damage and wear. The procedures for inspection and dismantling/cleaning/lubrication are available on the 997 GT3 stickies section-

Also, inspect your CL caps and make sure the O-rings are intact. If not, water gets in and can eventually corrode the locking pins. The O-rings are not ordinary and cost about $10 each at the dealer-

JB911

Well, I surfed through stickies and couldn't easily find the pdfs on CL and hubs
These are the ones I have: