AO

Read #20 below for the update.

I'm 3/4 of the way through putting my new cross-drilled rotors/pads on. Started at the pass front, and am now finishing up on the driver front. I cannot for the life of me get the 2 allen-head bolts to budge! Unfortunately I don't have a 10mm socket head, so I'm using a 10mm allen wrench with a deadblow hammer. Worked like a charm on the pass-side. But I noticed that the "head" is starting to strip out. I doused it with plenty of PB blaster and let it sit while I did the rears, but it still won't budge. I just squrited some more on there before I go to bed in a few mins.

I was thinking of picking up a 10mm alled-head impact socket and use my impact wrench. I could also try putting a cheater-bar on the allen wrench and see if it'll come off, but I'd like to hear other people that have BTDT.

Thanks in advance. I'll be back on-line tomorrow AM. CU!

bgrabner

Hey Andrew - I understand the frustration - I had a couple of issues with my shock replacement this weekend. Fortunately for me, the hex bolts weren't a problem. Anyway - I would highly recommend a 10mm hex socket head (actually, I would recommend a whole set) and a long handled socket wrench. The socket head just seems to set better in the hex bolt than the allan wrench, and the socket wrench will give better leverage.

Also, I advise patience - I had a real problem with the 12mm bold on the drivers side shock mount - I was so freaking pissed off last night at it I doused it with WD-40 and let it sit overnight, tapped at it with a hammer this morning, and finally got it to budge

Good luck!

Bill

Ed Scherer

BTDT -- when I was doing the caliper upgrade to Big Reds about three years ago.

After I rounded it off without ever budging it, I wound up having to drill it out.



It delayed the rest of the installation a couple of days while I got the replacement bolt.

I'm pretty sure if I would have had my air impact wrench at that time, I would have made quick work of this.

BTW, the one that gave me trouble was one of the driver's side ones, too.

Garth S

The impact wrench is the way to go .... set on a low pressure initially, and 'impact' in both directions: it is the shock that breaks the corrosion film. As a last resort, turn the setting on 'full'.
If applying straight torque with a bar & socket, there is a far greater opportunity to twist the bolt off.

AO

Ok, I see what I need to do then. I'll go and get a an impact set today during lunch. Hopefully I'll be able to report progress tonight.

doug928

Good luck Andrew - I just finished mine last weekend and had to drill out one of the bolts since even with and impact wrench the bolt wouldn't budge and the head started to round out - what a PITA. Mine was the drivers side also.

Ed Scherer

Hey... maybe, just maybe, a dab of anti-seize might be called for when that (or a replacement) bolt goes back in.

AO

I use that stuff everywhere! I never really understood the benefits of antisieze until I stated working on my own cars.

Doug-
I cringe even thinking about it, but how did you get teh bolt out after drilling it out? Did you use an easyout? How far did you drill down? Just planning ahead!

Ed Scherer

That Q wasn't directed at me, but in my case, it turned out to be extremely easy to drill the top of the bolt off (that's what's in the photo in post #3 of this thread; click it to get a much bigger version). Probably 1 cm of drilling, max. Just select a bit a little larger than the shank of the bolt. A really hard bit (I seem to remember getting a $10+ bit for this). When you're done, you'll have a nice bushing to add to your collection.

In my case, once I popped the top off the bolt and lifted off the caliper, the remainder of the bolt was very easy to remove with some Vice Grips. Once the stress is off those bolts, they're usually remarkably easy to turn.

AO

Thanks Ed. I'll pick up a hard bit too - I just have this feeling.

A co-worker who use to work at a brake shop said to use some stuff called Kroil or Croil. He said it's must stronger than PB Blaster. Anyone have experience with this stuff?

Gretch

Andrew, here is what I do, and it works very well. I have a pipe that is about a foot long and it fits over the long end of the allen wrench. (it is actually an old paint scraper so it has a 2inch flat on the end of it which makes getting leverage easier. (Get a new allen wrench BTW). Using the pipe for leverage, I am able to remove the bolts. The dead blow is less effective because there is too much flex in the wrench so a lot of the energy is lost.....My Tahoe also has allen bolts for the calipers so the set up has been tested many times.....worked like a charm when I did my GT brakes.
And before I used this method, I tried the dead blow method....all I did was destroy an allen wrench.
Best of luck.

AO

Gretch-
Surprisingly, the allen wrench is holding up very well to the abuse. But you're right about the flex and wasted energy. I don't know why i didn't think about the cheeter bar until this morning. I've got some varying lengths of pipe (for my pipe clamps) that will work perfectly. But I think I'll still try and locate the impact hex bit this afternoon - speaking of which, it's looking like it might be almost time to head out... I love tool shopping!

the flyin' scotsman

Andrew............tap the short end of the allen wrench into the bolt head to ensure its fully seated. This way you should get minimal/zero slippage when you apply the cheater bar high torque. Take care to look where your knuckles will hit if the bolt suddenly breaks free.

Garth S

Kroil, my (t)rusty companion , resides on the shelf beside a jug of anti-seize ....

AO

Just went to the local auto-parts store and asked for Kroil. The guy said he'd never heard of it. This falls into my philosophy that the best products are never easily obtained. This stuff must be the cat's a$$!