Stripped caliper bolts in Birfield (1 Viewer)

[ntsqd]

Just having second thoughts. The oem bolts are grade 11. Is a helicoil really up to the task?
They are grade 5 at best.

Where did you get that?

Better yet, do you think that cast steel part that stripped is equal to "grade 11" and that the Heli-coils are less strong than the casting?

I abhor the 1/2-13 option, it's just wrong. Doesn't mean that it doesn't work, but doesn't mean that it is right.

 

[Randy88FJ62]

Where did you get that?

Better yet, do you think that cast steel part that stripped is equal to "grade 11" and that the Heli-coils are less strong than the casting?

I abhor the 1/2-13 option, it's just wrong. Doesn't mean that it doesn't work, but doesn't mean that it is right.

ntsqd,
I understand that fine threads of the same bolt diameter will be stronger in tension and shear. I also agree that fine threads have less tendency to loosen under vibration.

I chose to go with 1/2-13 because that was the helicoil kit my friend had at the time. It was free so that played a big factor when I fixed my knuckles years back.

Coarse threads have greater resistance to stripping and are easier to install / remove.

I feel the 1/2-13 may not be the best choice but it works for the application without any problems. I did go the extra mile and lockwire my caliper bolts to prevent backing out.

The best solution I can see it going with a keensert and using the original hole ID of 12 x 1.5. That would have cost quite a bit of money and required a machine shop. I have access to one here at work and the thought has crossed my mind since I have spare knuckles in my garage.

 

[ntsqd]

Oddly none of those reasons is why I feel that it is wrong to use the 1/2-13. In my driveway only mixed vehicles get mixed fasteners (& thankfully have now all been sold off). Metric vehicles stay metric to a pretty extreme extent (AN threads being the most common and usually the only exception). SAE vehicles stay SAE with no exceptions. Makes knowing what tools are needed much simpler & lighter.

Since the caliper's location depends on the fit of the bolt to the hole, I severely dislike the drilling of the caliper body because it might just happen that that body is then rebuilt at some point in the future and someone not knowing about it being drilled won't get a caliper that is in the right location. Can't guaranty that they will never be rebuilt because once the vehicle is out of your control it could happen (sold or wrecked).

 

[hj 60]

So I needed the helicoil fast but still waiting. (forgot house adres, stuff came from Germany, was send back by Dutch post, refunded, ordered again...) A Dutchman is not a German what is Verkaufsprotokollnummer ?
My house number was stated behind the Verkaufsprotokollnummer: no idea why.

The Helicoil set from germany, I dont know why but every time I look the thing is 15 euro cheaper
(I use self destructing cookies so the website should not know it is me again) but some how it counts the hits I suppose.
The cookie thing normally ADDS money if it senses your back in the store)
http://www.tola-tools.de/HELICOIL-Sets-Tools/Repair-Sets-M2-M16/HELICOIL--Repair-Set-M12x1-25.html

step tapper:
http://www.tola-tools.de/HELICOIL-Sets-Tools/Tools/Step-Tappers/HELICOIL--M12x1-25-Step-Tapper.html


At least I got the tools from a shop that was closed a day later due to a hurricane destroying the roof (in the netherlands that is an exeption, I drove to much and changed dutch climate...)

I ordered two m12 tools to tap the helicoil and hopefully tomorrow the helicoil will be delivered. (12 hours to midday)
EDIT: none of these tools fit on the tapper (9x9 mm)

I used crap eye protection while grinding and had an iron piece in my eye for two days, learned a lesson... 48 hours without sleep means you better see a doctor, now ok.
Also had some severe burning wounds on my arm from welding above my head, the stuff burned trough my clothes and was hissing away on my skin this buy was approved by the

 

[hj 60]

The drilling and tapping worked out, but the drilling is almost impossible to do straight without mecanical help.
So we tapped a bit with an angle and I was pretty sick of that.

But no worries, I was assured it will be fine (it holds the specified torque perfectly and the slight angle was not that bad)
-No helicoil can be inserted by hand (the original is so clean I could turn the bolt in by hand easily)
-Helicoil can NOT be inserted from the wrong way (the snap off bit may not snap off properly and the end may damage your bolt)
-if the helicoil comes out when I remove the bolt insert it back in, or replace with a new one, I cant stand it but hey I am driving again.


Maybe I should have bought the HELICOIL M12x1,25 Step Tapper with guiding thread.
For HELICOIL® M12x1,25 inserts
Tapper uses damaged thread as guide to center coaxial bigger thread for Helicoil inserts. Allows perfectly aligned tapping for Helicoil inserts in one step.
What about the drill? Now I get it: drill in a few millimeter, TAP with the step tapper, and then drill the rest!
STEP TAPPER IS COMPULSORY, you want 100% proper work or not?

17.36 mm is the available lenght, 3 mm before it hits the brakedisk.

The box has 12/18/24mm helicoils so it seems I will be using the 1.5D=18mm... trying to follow the instructions...

drilling form engine outwards is impossible:

If I could turn back time...

I did not turn back: to many iron flakes all around, used the air compressor and drilling oil to clean, but I advise to turn it all the way trough.
by hand, no force needed.

This should have been a slight 1/2 more turn. (I think)
The proper way seems to be:
mark the start of the original thread.
turn the helicoil 3/4 turn further. So one half and a quarter turn further in.

 

[Randy88FJ62]

Nice pics. Should do a quick writeup and post in sticky. Lots of people ask this question and I've never seen pics.

 

[hj 60]

Thanks Randy, I've added info, wish I knew before I started this...
I can add the pictures as attachments so they will be here, if my site hj60.freeforums is wiped all pictures will be gone.

The web is getting old, people die.
Like Wayne Weber who long time ago helped me with an chrysler outboard.
He was not healty and getting older, now his website www.brokeboats.com is gone, with tons of boat knowledge.
Thank you so much Wayne, I'm still afloat man.

http://www.zoominfo.com/CachedPage/...01-26T03:41:14&firstName=Wayne&lastName=Weber

Who,What,When,Why, Where in the world is:
Wayne Weber
I was born and grew up in the South Carolina Lowcountry; a beautiful area with the Atlantic ocean 20 miles away, six rivers meet the coast within 40 miles of my home. Once these rivers start to overfill the Atlantic, we use the extra water to keep the famous Santee Cooper Lakes full; 15 miles from my shop. Whatever water is left over is spilled into the Great Cypress and Four Hole Swamps; right next door. About nine hundred tidal creeks hook every thing all together. Needless to say, I grew up around a lot of boats.
I operated a small independent marine repair shop and my father did before that. I serviced all brands of outboards and inboards, including all aspects of boat and trailer repair.
I am factory trained and certified on Johnson & Evinrude (OMC) and Mercury & Mariner outboards. I try to stay up to date by attending various technical and service seminars.
I'm not a computer tech and don't have any "geek" friends that happen to know any more than I do. Since I can't afford to pay anyone to build web pages I'm doing this one night at a time.
If you notice a problem or error on any of my pages, PLEASE let me know. Any suggestions or help would also be greatly appreciated.
I'm always willing and happy to learn a little more!

William Wayne Weber March 2, 1951 - April 24, 2011

 

[Colorado fj62]

Well I had both the caliper holes stripped out on one side by the ham-handed mechanic that did the last break job. One of the bolts had fallen out altogether I don't know how long ago and the other would not go much past finger tight. So I attempted to do helicoils on both holes and it seemed to go pretty well. Unfortunately I didn't get them perfectly straight enough so now I can't get the caliper back on at all. Each helicoiled hole works fine by itself but can't get them both in. The are off just enough... @#$%^%&*
so.... I have a couple options that I can think of.
1) get a new/used birfield (don't know where to find one and pretty sure it will be expensive) or
2) drill out the hole and tap to the next bigger size. Might have to drill out the calipers to fit bigger bolts.
3) drill out the caliper holes just enough that I can put in the missaligned bolts (not to thrilled about this idea) or
4) open to any other suggestion. Please

 

[KLF]

I think you mean knuckle, not the Birfield. And they are not hard to find, post in the Wanted ads, you should be able to get one.

If not, #3.

 

[FJ60Seth]

I've read that timeserts are better for an application where parts are often disassembled, but many use helicoil successfully. A dab of blue loctite will keep the bolts from moving.

 

[hj 60]

That is bad (cant say what I want due to forbidden language policy on his forum),
Step Tapper should be sold with every set, but let that be a lesson for the next guy.
I dont like modifying good parts, but maybe yo can keep the best aligned one and redrill the worst one?
so use the tools you have, redrill and resinsert and see what happens,

IT...

 

[the gimpey one]

Just got back from Logans Run in Uwharrie national forrest with the ONSC guys. Lost a caliper around 40 miles out. Trollhole brought me a replacement caliper and the bottom bolt stripped! Of course it is one that has been retapped to 1/2". Can I helicoil to a smaller size like the factory bolt size for example? If so do I still need to run a tap or just insert the helicoil?

 

[hj 60]

No? before you drill, can you remove the old stripped wire and just put a new same size one in. Also the old caliper must have been drilled,the new one is not.

Helicoil will use the original factory bolt, but that is smaller than whatever was in there when you stripped it.
(1/2) inch = 12.7 millimeters
Original is 12 MM x1,25

So the only way is up, so next step is 12,9 = 13 mm. (=0.511811024 inches?) cant you rebuild the old caliper and drill it (or use it for testdrilling)
So as I understand:
1-bottembolt needs new 1/2" or new heli or insert size 12,9mm or more
2-caliper bottom hole needs drilled to new size heli/insert.
3-need new bolt same size as new heli/insert
4-you might as well do a disk swap and knuckles, elbowgrease is best when unexpected... good luck

 

[the gimpey one]

The caliper holes have been mad bigger. Was hoping the helicoil would take up the .7 difference with the bolts. Guess i will have to helicoil at 1/2". I want to replace the knuckle but time is not my ally right now.

 

[Colorado fj62]

Well I finally got my cruiser back on the road. Found a new knuckle and put it all back together. The knuckle, gaskets and seals were about $225. A GIANT pain in the @$$. I agree that a Step Tap (or taking the knuckle off and using a drill press) is mandatory for this repair. Another lesson learned at the School of Hard Knocks. I should be getting my PHD from that fine institution in the mail any day now. Thanks for all the advice, guidance and not ribbing me too bad.