Stripped caliper bolts in Birfield

Joined
Mar 11, 2013
Messages
366
Location
Treasure Coast, FL
So I rebuilt both airfields but when I got to the passenger side one, the brake caliper bolts were extremely difficult to remove.
I ignored it and continued with the build.
Upon reassembly, I realized that the caliper bolts were cross threaded by the last monkey to work on this vehicle. He probably threaded and blasted them using an air gun.
I muscled the bolts in but threads have been damaged and I dont think theyre holding well. I think the threads in the birfield are the damaged ones.

What is the best remedy?
Should I just buy a used knuckle and replace? My only concern here is that I will have no idea how to shim the trunion bearings properly. Where as on my existing knuckle, I just reassembled the shims that were already on it.

Or should I drill the caliper bolt holes and tap & tie them for a bigger bolt?
I suppose I'd rather tap & die than worry if it is shimmed incorrectly.
Thoughts?
 

ntsqd

technerd
Joined
Apr 26, 2007
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Upper So. CA
Helicoil is the best solution and I believe them to be stronger than original. The pain of the price will only be felt once. Through there are other replacement thread solutions that are stronger, none are as easily found and implemented.
 

Mace

rock scientist..
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Helicoil is the best solution and I believe them to be stronger than original. The pain of the price will only be felt once. Through there are other replacement thread solutions that are stronger, none are as easily found and implemented.

yep...

Fixing things right the first time only costs once.
 
Joined
Mar 11, 2013
Messages
366
Location
Treasure Coast, FL
That's why I love this forum. There's usually a consensus on how to do something the right way, not necessarily the cheapest or easiest.
So I ordered 2 new oem caliper bolts from a dealer.
Can anyone tell me what the thread size/pitch, etc the oem bolts are ? I need that to order the helicoil.
Thanks
 
Joined
Mar 11, 2013
Messages
366
Location
Treasure Coast, FL
I ordered the bolts from Village Toyota and also ordered a Helicoil kit for M14 x 1.25 bolts and guess what?
The bolts I received are too small for the Helicoil M14 inserts, which leads me to believe the bolts are not M14.
The link posted above was from the 25-20-45-55/56 series forum.
Which probably means the wrong bolt size/

Does anyone know what size bolts are in the Series 60 (FJ62) brake calipers?
Thanks
 
Joined
Dec 28, 2010
Messages
962
Location
Moscow, ID
Generally speaking, on a Toyota of our vintage, if the bolt takes a 12mm socket, it's m8, if it takes a 14mm socket, it's m10.

I can't help with specifics about the caliper bolts, though; I haven't had to tear into my brakes yet.
 

hj 60

JT1W0HJ6000960839
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Aug 1, 2012
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Netherlands Hengevelde
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www.tapatalk.com
I ordered this set but you need to also buy the wrench to turn the taps.

http://cgi.ebay.de/ws/eBayISAPI.dll?ViewItem&rd=1&item=260753636123&ssPageName=STRK:MERFB:IID

Yep size 12x1.25 and partnumber bolt is:
90101-12060‏



Only enter the new thread drill/tool the same way as the original bolt.
I am waiting for the mail to arrive and deliver the set.
I want to try to drill from the engine side outwards.
also tap that way.


The brakedisk has about 1 cm free space before the drill will touch it, after setting preload not eager to take it apart again...


Did you do the rest of your brake?


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I always use a dremel to clean the thread especially if torkqued.
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In total 4 of the 8 rubber protection sleeves were busted, dirt entered and so 4 pistons had corrossion, cleaned up and replaced:
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First I use air to pop them out (DANGER! Watch out for your 8 bar canon brake caliper, before you press the trigger look at your fingers :) ) Then clean and reinsert and next air one after that you can get them out with some normal force.
A grease gun is also very usefull and will for sure pop them out, but you need to clean very well afterwards.

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The helicoil set arrived, but the tap will not fit on any wrench (its a square 9x9 mm), and will not fith on both 12mm tools I bought.
The tap is the most important step so I need another tool to turn the tap and make a new thread.

The mandrel (8x8mm) fits on all the tools, Why do they use two different sizes...?

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Last edited:
Joined
Apr 14, 2008
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North of LA California
The caliper bolts are ØM12mm X 1.25mm pitch. This is a common occurrence. The cheapest correct solution I found was to buy a Ø1/2" X 13 pitch helicoil kit. Then purtchase four socket head cap screws Ø1/2X13. You can then drill a few holes in the tops of the allen bolts and lockwire them together.

Lockwire guarantees they will not come out unless you want them to.

I do a lot of wheeling on washboard roads in death valley and the lockwire solution is comforting.
 

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