Can helicoils handle the same stress as an original bolt?

[AllanS]

I stripped out the threads on the left front brake carrier, and a new one is almost impossible to find- all the usual sources of auto wreckers just laugh at me when I tell them that I need a brake carrier for a '90-'93 850i, and BMA can only get one new... from Germany... at a time estimate of 1-2 weeks... for 140$ plus shipping.

So, do you think that using a helicoil would be a good solution? I'm going to go buy one of the kits tonight or tomorrow- 6$ is a lot cheaper that 140$ in any case. I'm just worried about the side to side stress that these bolts endure- it will probably be able to torque up properly.

Allan

[Hector]

is an excerpt from Pelican Parts Forum. I believe these guys are talking about heat exchanger studs in Porsches: "The inserts, brand named "Helicoil", are used at the NAPA machine shop I used to work at. According to the manufarcture they are indeed stronger than a normal threaded hole in alum. The reason is that the Helicoil distributes the stress over a wider cross section, true this means that the hole is bigger, but the helicoil and the stud are steel (actually stainless in the helicoils case) so the threads don't seize to the stud causeing strip out. Personally I don't like the step down studs because the ones I've seen are 9mm at the shaft and then stepped down to 8mm. This caused a fit problem (read: "time for the the hammer")with my after market SS heat exchanges, this problem didn't exist with stock studs."

Here's the link. Just go down to the 8th post.

http://www.pelicanbbs.com/posts/199.htm

[Dirty.Deeds]

A helicoil will take the original torque for that application as long as it is correctly installed.The Helicoil itself is just a wire insert but you have to Tap the hole bigger and then insert it and seat it properly.I would personally recomend you take it to your nearest engineering plant and get it done there.I am an engineer and have seen alsorts of attempts at helicoiling that have been done at home with a pistol drill which oversizes the hole for tapping.In the UK most engineering plants charge a small fee for this service.

[ryan roopnarine]

i found on car-part.com. as there is no criteria for brake carrier, i just ran one for 850si front brake rotors...maybe you can give them a call and see how much they want for it

Year
Part
Model Description Condition Stock# Price Dealer Info
1994
Brake, Front(Rotor)
BMW 840i YELLO-BAG $Call Action Auto Wreckers USA-NY(Massapequa) E-mail 1-800-562-8811
1994
Brake, Front(Rotor)
BMW 840i YELLO-BAG $Call Action Auto Wreckers USA-NY(Massapequa) E-mail 1-800-562-8811

1991
Brake, Front(Rotor)
BMW 850i *r/f P7582 $25 A-Reliable Auto Parts USA-IL(Blue-Island) E-mail 1-800-385-2385

[Bill R.]

holding area of the bolt. Mercedes aluminum blocks have helicoils installed from the factory in the holes that the headbolts thread into. They went to this as a fix for the head bolts pulling the threads out of the block when the car was overheated.





I stripped out the threads on the left front brake carrier, and a new one is almost impossible to find- all the usual sources of auto wreckers just laugh at me when I tell them that I need a brake carrier for a '90-'93 850i, and BMA can only get one new... from Germany... at a time estimate of 1-2 weeks... for 140$ plus shipping.

So, do you think that using a helicoil would be a good solution? I'm going to go buy one of the kits tonight or tomorrow- 6$ is a lot cheaper that 140$ in any case. I'm just worried about the side to side stress that these bolts endure- it will probably be able to torque up properly.

Allan

[632 Regal]

holding area of the bolt. Mercedes aluminum blocks have helicoils installed from the factory in the holes that the headbolts thread into. They went to this as a fix for the head bolts pulling the threads out of the block when the car was overheated.