Brake Disc Screws Rusted 987.1 2.7L

Brake Disc Screws Rusted 987.1 2.7L

Author
Discussion

Heaveho

5,282 posts

174 months

Friday 5th June 2020
quotequote all
tozerman said:
My advice would please do no follow this advice.
Simply bashing the disc off the hub with a fooking big hammer runs the risk of warping the hub and brinnel the bearings
My advice
It doesn't. And it's a last resort.

Klippie

3,122 posts

145 months

Sunday 7th June 2020
quotequote all
My tried and trusted method...centre punch the screwhead use the thread tapping size drill and it will remove the screwhead in one go, then using a set of grips turn out the remaining part of the thread, if its solid flush off the thread to the face drill out and re-tap.

bennno

11,607 posts

269 months

Sunday 7th June 2020
quotequote all
Heaveho said:
To be fair here, if you're replacing the discs, get the caliper out of the way and beat the old discs off from the back. The heads of the retaining screws are so small they'll just snap off without much aggro, and getting the thread out will be easy because they won't be tight anymore. You don't even have to replace the screws if you can't be arsed, the wheels and calipers will obviously keep the discs on! Lots of cars do without the screws.

I'm just in the process of doing mine on my 987, they all came out no bother after getting the right sized screwdriver into them and giving them all a clump with a hammer to shock them, then trying to tighten them slightly before loosening. Never needed more than this. I've had way more aggro with the caliper bolts than them.

Edited by Heaveho on Friday 5th June 01:07
I’d not follow that advice, risk of causing other damage. Personally I’d drill bolts out if an impact driver doesn’t work. My son who is 3 years in to his training as a mechanic recommends the extractor bits as best method if impact driver doesn’t work.

Heaveho

5,282 posts

174 months

Sunday 7th June 2020
quotequote all
bennno said:
Heaveho said:
To be fair here, if you're replacing the discs, get the caliper out of the way and beat the old discs off from the back. The heads of the retaining screws are so small they'll just snap off without much aggro, and getting the thread out will be easy because they won't be tight anymore. You don't even have to replace the screws if you can't be arsed, the wheels and calipers will obviously keep the discs on! Lots of cars do without the screws.

I'm just in the process of doing mine on my 987, they all came out no bother after getting the right sized screwdriver into them and giving them all a clump with a hammer to shock them, then trying to tighten them slightly before loosening. Never needed more than this. I've had way more aggro with the caliper bolts than them.

Edited by Heaveho on Friday 5th June 01:07
I’d not follow that advice, risk of causing other damage. Personally I’d drill bolts out if an impact driver doesn’t work. My son who is 3 years in to his training as a mechanic recommends the extractor bits as best method if impact driver doesn’t work.
As I said, there isn't, and it's a last resort. I can keep saying this all day for those who need it repeated.

RobXjcoupe

3,168 posts

91 months

Monday 8th June 2020
quotequote all
bennno said:
Heaveho said:
To be fair here, if you're replacing the discs, get the caliper out of the way and beat the old discs off from the back. The heads of the retaining screws are so small they'll just snap off without much aggro, and getting the thread out will be easy because they won't be tight anymore. You don't even have to replace the screws if you can't be arsed, the wheels and calipers will obviously keep the discs on! Lots of cars do without the screws.

I'm just in the process of doing mine on my 987, they all came out no bother after getting the right sized screwdriver into them and giving them all a clump with a hammer to shock them, then trying to tighten them slightly before loosening. Never needed more than this. I've had way more aggro with the caliper bolts than them.

Edited by Heaveho on Friday 5th June 01:07
I’d not follow that advice, risk of causing other damage. Personally I’d drill bolts out if an impact driver doesn’t work. My son who is 3 years in to his training as a mechanic recommends the extractor bits as best method if impact driver doesn’t work.
Extractor will be tiny for a 6mm screw. You will be hard pushed to drill that on centre by hand with no experience. Tap size is 5mm so only gives you a max size of 4mm for a screw extractor.
Then the screw material is tough. A normal drill bit that small will struggle. A solid carbide bit will be best like a hot knife through butter. Then for all the time wasted to fit an extractor you might just use a 7mm drill to take the countersunk head off, remove the disc then unscrew the studs left behind

magycks

Original Poster:

215 posts

66 months

Tuesday 16th June 2020
quotequote all
Ended up having to drill the screws out. No amount of rust penetrator, smashing an impact driver, hammer etc for 30min would get them moving.

Good news is I replaced the front 2 discs

The bad news is that my friend and I snapped a brake line (i think?)!! Can't believe it! Fluid all over the floor...

I think this is the part I need to replace (just to make absolutely sure i'm ordering the right thing). Imagine it will be a struggle due to the rust

https://www.design911.co.uk/fu/prod137872/Caliper-...



Edited by magycks on Tuesday 16th June 23:32

pete.g

1,527 posts

206 months

Wednesday 17th June 2020
quotequote all
Do yourself a favour and grab a bargain:

https://www.eurocarparts.com/p/pagid-3-piece-flare...

otherwise your next post will be asking advice on how to remove rounded off brake hose nuts.

I don't own Euro Car Parts!

mickyh7

2,347 posts

86 months

Wednesday 17th June 2020
quotequote all
Do yourself a favour and just find a small Independent!
It'll cost next to nothing, and take no time at all.
Bread and Butter job to these Guys.
And, nothing else will be broken.
With the greatest respect, if you need help and advice to remove a tight bolt, you should not be touching brake lines!

magycks

Original Poster:

215 posts

66 months

Saturday 27th June 2020
quotequote all
I bought the new brake line and fitted it without any issues. The old bolts were quite rusted but got them off with rust penetrant and hex sockets (I cut the old metal line with pliers to get a socket on to minimise any risk of rounding the bolts). Did some light impact wrenching on the higher bolt and overall an absolute breeze versus what I was expecting.

I kept bleeding the brakes on all 4 corners and kept the reservoir topped up with DOT 4... for a lonnggg time but I've now realised that because the reservoir had run so dry I need to use a computer to activate the valves (as the vehicle has traction control). No wonder our brake bleeding efforts weren't getting us anywhere! Does anyone know if I can get a ECU reader that can do this inexpensively / does anyone have one I could borrow near south-west London?

"For cars with traction control or Porsche Stability Management (PSM), you need to use the Porsche System Tester 2 (PST2) in order to activate the valves in the hydraulic unit during the bleeding process."

RSTurboPaul

10,323 posts

258 months

Saturday 27th June 2020
quotequote all
Well done on getting the mechanical bits done - satisfying to save some cash, although being halfway through with something broken and one does wonder if one has made the right decision... lol


Hope you can get the electronics sorted. This is why old, simple cars are best wink

There might be a Porsche independent garage that could do it for much cheaper than a proper Porsche garage.

magycks

Original Poster:

215 posts

66 months

Saturday 27th June 2020
quotequote all
Klippie said:
Over the years having to replace disc's I've found the retaining screws are made from chocolate and very easy to drill out with normal HSS drill bits and a squirt of cutting fluid, the screws serve no pursose apart from keeping the disc on the hub there is no load on them, there is no requirement to make them from hardened steel.

Draw a file across a new one and you'll see how soft they are.
I had to drill out the screws on the front but the rear disc screws came out easy with a few bangs of my new impact driver. The retaining screws are certainly useful but by no means required

Mike1960

11 posts

49 months

Saturday 27th June 2020
quotequote all
Hi, you should be able to bleed the brakes without activating the ABS unit. The valves will have held the fluid in the unit.
The 986 brakes and clutch share the same fluid reservoir and if this has run dry then you may need to also bleed the clutch. This is a b*****d of a job. Have a look on YouTube and take your time.

magycks

Original Poster:

215 posts

66 months

Saturday 27th June 2020
quotequote all
Mike1960 said:
Hi, you should be able to bleed the brakes without activating the ABS unit. The valves will have held the fluid in the unit.
The 986 brakes and clutch share the same fluid reservoir and if this has run dry then you may need to also bleed the clutch. This is a b*****d of a job. Have a look on YouTube and take your time.
was bleeding all 4 corners in the correct order repeatedly but sadly didn't work. No improvement at all.. guessing because the brake fluid had a whole week to drain out and probably need the software..?

Mike1960

11 posts

49 months

Saturday 27th June 2020
quotequote all
How much fluid did you bleed through. The entire system is about 1.5ltr.
Have you used more than that?

DH986S

17 posts

205 months

Sunday 28th June 2020
quotequote all
Have you bled both sides of the calliper that you replaced the brake line on, I had a similar issue when I replaced these lines.

magycks

Original Poster:

215 posts

66 months

Monday 29th June 2020
quotequote all
Mike1960 said:
How much fluid did you bleed through. The entire system is about 1.5ltr.
Have you used more than that?
Bled through over 1 litre of fluid but no air was coming through for the last 45mins we were doing it.

DH986S said:
Have you bled both sides of the calliper that you replaced the brake line on, I had a similar issue when I replaced these lines.
Yes, we bled all 4 corners and both sides of each calliper in the correct order. We did this for a very long time but it doesn't work. We've bled brakes many times before on other cars without any issues hence the confusion until we googled and found out we needed the computer to put the car in bleed mode.

If anyone has a computer that will put a 987 in bleed mode or could recommend a low cost tool that will do it, that would be really helpful.

RobXjcoupe

3,168 posts

91 months

Monday 29th June 2020
quotequote all
Just wondering, what happens if you turn the ignition on, then bleed the brakes? So in effect the abs unit is actually active but obviously not being driven

magycks

Original Poster:

215 posts

66 months

Monday 29th June 2020
quotequote all
RobXjcoupe said:
Just wondering, what happens if you turn the ignition on, then bleed the brakes? So in effect the abs unit is actually active but obviously not being driven
We tried this as well but to no avail. We spent a crazy amount of time brake bleeding and only once we gave up did we realise we need the software to do it properly

I don’t know if some kind of crazy traction control activating driving could make any difference - not that I would want to try when the brakes struggle on a 5mph to 0 stop as it is!

Think we just need to get a hold of the computer by the sound of it... unless there’s some other way

RobXjcoupe

3,168 posts

91 months

Monday 29th June 2020
quotequote all
Jack up both the rear wheels, get it sitting securely and safely on axle stands. Start up the engine, put into gear so the wheels are now rotating say 10-15mph, dip the clutch and gently press the brakes. The abs light will be on as the front wheels are stationary. Are you using the ezibleed pressure bleed? I would say get it hooked up so when the abs activates it will allow the pressurised fluid into the system. Then fingers crossed you should be able to then bleed the calipers.

mickyh7

2,347 posts

86 months

Monday 29th June 2020
quotequote all
mickyh7 said:
Do yourself a favour and just find a small Independent!
It'll cost next to nothing, and take no time at all.
Bread and Butter job to these Guys.
And, nothing else will be broken.
With the greatest respect, if you need help and advice to remove a tight bolt, you should not be touching brake lines!
I refer you to my past post!