As the​ title states, I stripped the threads on the pedal inserts on my left crank arm. I know the best thing to do would be replacing the whole crank set and I might just buy the Shimano acera M361 to do that, but I wanted to know if there is anyway to permanently fix my current crank arm?

Thanks
-Sam

Yea, between getting the 9/16 20tpi tap and those threaded inserts buying a new set makes more sense, supprisingly.

As for the crank, right now I'm running the stock generic SBC son of strongarm 22-32-42. Not sure of the BB specs though, nor what i would measure.
-Sam

Depends on how badly the threads are boogered up.  If just a little cross threaded then a tap should clean it up enough to reuse.  If we're talking full on "I rode with the pedal loose for 10 miles at USNWC" galled then you'll need to ream, thread and install a thread insert.  Those tools and parts look like this....

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$10 for the part and $15 for the labor will get you back on the trail without having to add to the landfill.

Just remember which direction to run the tap. I cannot remember which side is RH thread and which is LH. If I remember right the LH side has to be tapped from the inside of the crank arm.

MARK ?

Good point on the thread pattern, I don't understand why left loosy right tighty doesn't apply the the (from above)RH crank but there's probably a good reason.

On a side note​, I realize what I said before, but does anyone around Sherman have a square taper crank puller I could borrow for all of 5 minutes to remove the crank. I'm thinking I'll need to stick the arm in a flat jaw vice with a towel around it to have a chance of getting the threads straight.

Btw, quick crappy photo of the few threads left
Thanks for the help everyone 
-Sam

It is the right one isn't it, there's my keen sense of direction. And yea, threads are ​pretty screwed, or really it would be unscrewed.  The pedal slides in with a 1/16" of space on each side and only grips one row of the few threads left. 

I'm debating whether to get the the arms fixed or just get  that m361 I mentioned. The actual rings are somewhat worn and probably deserve a retirement. Also, I understand how the repair thread is installed but how is it kept from unscrewing? I don't think they're soldered and I can't see the labor involved with milling out a key way/seat on the arm/pedals costing $15, even with that Modelo added to the payment
-Sam

A liberal coat of Red Thread lock holds the insert in.  The left side crank arm threads are backwards because if they weren't the pedal would have a tendency to unscrew.  Ask anyone with an Italian road bike with and Italian bottom bracket and they'll tell you why they have to always tighten and/or thread lock their bottom brackets.   

BTW that reverse thread tap is bike industry specific.  You will not find that at an auto parts or hardware store.   

If the rings are worn than it's probably cheaper just getting a new crank set.  Make sure to check bottom bracket spindle length compatibility. 

The inserts are made by Unior and are similar but not the same as a Heli-Coil (which coming from an automotive background I'm all too familiar with. )

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Seems to be a no brainer for just buying a new and complete crankset.

ciao
Santana

That bike's a classic!  Don't ever get rid of it!

Thanks for the compliments on the bike. I'm absolutely loving it. Although I'm kinda modernizing it slightly, i still want to keep it semi-stock. 

Might have to eventually fix the original crank though, just to stick it back on and show it off as a display bike.

Hi Brian, The crank was all my fault. After all should of noticed that one was a lot harder to install. Good lesson for the future though. As for upgrades, unless I absolutely need to change something, I'm planning at stopping at the bar/stem. After all I could also move it over to a compatible future frame and save a good $60 or more. 

Don't worry about the original cleats, pedals, and manual, unless your ever at Sherman or Purser or just near there. If you ever are let me know and I'll try to pick them up.
-Sam