Boxerworks.com

Yes, a"stretch" is a more accurate description than "bind".
They are probably variable pitch as the threads get closer to the head.
That would pull back, or "stretch", the portion of threads already engaged.

I am curious about this too. I will try to take some measurements the next time that I change them.

The "stretch" bolts of my era would thread in by hand as easily as any. Have they changed?

Duane Ausherman wrote:The "stretch" bolts of my era would thread in by hand as easily as any. Have they changed?

The ones that used lockwashers where not stretch bolts and could be re-used with new lockwashers.

The stretching of the new bolts (without lockwashers) takes place in the shaft flange area where the threads are exposed. If the where over tourqued or reused they may deform in the area where the threads are in contact with the trans flange.

what is the chance of using a case saver insert?
Guy

guy wrote:what is the chance of using a case saver insert?
Guy

This is probably a better application for a heli-coil. In steel, I would not think that you would need such large external threads. In our aluminum blocks, having the larger insert means more strength in the aluminum. I still have to post a summary of my case insert experience.

I wouldn't consider using any type of repair of that problem if I could get the part and install them for less than $400.00. Inserts don't seem a good solution. Helicoils seem like they wouldn't stay put. If one of those babies comes un-done, it could be mui inconvenient and possibly expensive.

To me, the idea of buying the tool and buying the part from Rob has the most appeal. As a matter of fact, before I checked page two of this thread and saw that someone else came up with it, that was what I was thinking of. In the end, someone pays for and ends up with a tool that could come in handy at a later date.

For the record, it seems like you wouldn't need to worry about balance because the bolts are not way out on a large diameter. It would be interesting if someone who has more experience would chime in on that issue. I'm assuming that the best oversize scenario would be if there is an English size that is just a hair bigger that it could be tapped to. Going to the next size within the metric system would be a fair size jump.

Chuey

I still wouldn't want one weird fastener in there. It is frustrating enough with all four of them the same.

And Brad wouldn't have to pay too much for my flange. I have seen the slideshow on his GPSr. He is my kind of guy!

Chuey wrote:...Inserts don't seem a good solution.

Hold the phone ! Granted, the best solution in this particular scenario might well be purchasing the used part ...
On the other hand, I have had excellent results with thread-inserts.
I have used them to repair about every fill and drain orifice on a BMW airhead MC
as well as other more critical applications, including but not limited to, cylinder studs ...
and without fail.

A stripped thread that renders a piece useless ?
If any one out there is trashing cast or machined BMW parts for the sake of a stripped thread –
please, let me know !
I'll pay shipping and be happy to take them off your hands !

justoneoftheguys wrote:I still wouldn't want one weird fastener in there. It is frustrating enough with all four of them the same.

A "weird" fastener ? Some will be more easily frustrated than others, eh ?
Why settle for a used part ? Who knows where it's been !
Get your ass up off of your purse and buy NEW – it's the 'Merican way !

I live just 30 miles from what used to be Air Head Salvage. I will send him a note to see if he has the flange. He has most stuff. He may even have the tool.

Failing all that, I will go with the idea of buying the tool, shipping it to Rob, and waiting for things to arrive. Thanks for the offer Rob.

I will let you know how this comes out - but it won't be for 10 days or more as I am headed out of town again and won't be doing much work.

Brad