bolts for girling calipers

[teigan]

i broke a caliper bolt trying to torque it to specs [23 ft/lbs]. i'm not sure it was original. i did notice it was rated 10. i plan to replace it with an 8 rating, but wondered if any of you know the correct length. thanks.

[lotusguy]

teigan said:

i broke a caliper bolt trying to torque it to specs [23 ft/lbs]. i'm not sure it was original. i did notice it was rated 10. i plan to replace it with an 8 rating, but wondered if any of you know the correct length. thanks.

Hi,

There is a spec for the rear caliper bolts in the manual of 75mm and 85mm respectively for the upper and bottom, but no spec for the front bolt. The manual just cites it as Front Caliper Mounting Bolt and a part #. I suggest pulling the one from the opposite wheel as a guide. Since they're cheap, why not replace them both?

I would further suggest that you use the same grade bolt as the original, otherwise you'll be using the wrong torque spec on it. The harder grade 8 bolt doesn't torque (twist) as much as the grade 10, so applying the same torque will result in an overtightened bolt which could strip the mounting bracket tap. Also, it always a good idea to torque a bolt in stages. If the spec is 23 ft.lbs., first tighten it to 12 and then go on to 23. This way, there's less chance of breaking it, and a better chance of setting the torque accurately.
Happy Motoring! ...Jim'85TE

[teigan]

good tips jim. i was doing it wrong, as usual. also, you answered my most important doubt of whether the bolts i took out were originals. they obviously aren't as the top and bottom were the same length on my rear calipers.

a sidenote that might be useful to those with the same brakes:
when i replaced the brakepads last month, i found the caliper pistons had not been rotated back into rachet position when previously serviced. i suspected this already since the pads were wearing dramatically more on one side of the rotor. bad enough a professional lotus mechanic hired by the previous owner did such shoddy work, but worse that i paid viking motor sports $250 for a complete safety check, and they didn't point out the uneven pad wear. another reason i won't let them work on my car, even though i can afford to pay someone to maintain my car.

[lotusguy]

teigan said:

good tips jim. i was doing it wrong, as usual... another reason i won't let them work on my car, even though i can afford to pay someone to maintain my car.

Hey,

Don't beat yourself up. I once spent an hour trying to put a head back on an engine, couldn't figure out why the studs wouldn't line up, until I finally realized I had the head
reversed ...DOOOOOOOH!!

Even after rebuilding countless engines, trannys and brakes, you have no idea how horrified I was to work on my Esprit when I first got it. What if I screwed up and did something really costly? But, once I got into it, I realized that it's just like any other engine, in fact simpler than many, much simpler than say, my 240Z, or MGB engines, which I could rebuild practically blindfolded.

Everyone screws up in the beginning, it's all part of the learning curve. The thing to do is stay positive, don't rush, work deliberately and slowly, and use the resources available to you, such as this forum. You'll be amazed at how quickly you improve.
Happy Motoring! ...Jim'85TE

>> Edited by lotusguy on Tuesday 1st March 04:05