915 Shift Coupler removal--how to free Set Screw?

[MIK911]

How to free frozen Set Screw (#26 in diagram)?
1st step in changing my coupler bushing, and I'm already stumped. Already bent 2 allen wrenches, used Liquid Wrench to lubricate, but after 22 yrs on my '86, that screw is petrified in there.
Any suggestions?




thanks

[450knotOffice]

I'd say drill it and use one of those fastener removal tools that they have at Sears. They're pretty cheap and are basically little tapered and hardened studs with sharpened serrated edges that will basically cut into the sides of the hole you drilled into the fastener and wedge themselves in. Then all you do is attach a socket wrench and unscrew it. The harder you turn it, the deeper into the fastener it wedges itself, so it won't "strip" out.

[khamul02]

I had one that was stripped and I ended up using a flat head screwdriver that fit into the stripped hex head. Then I used some vice grips the twist the screwdriver and the hex screw came out. It went pretty well and that screw was stripped to hell and back.

[3.2 CAB]

I hate to ask, but, have you been using metric, "L" shaped allen wrenches? Have you tried a socket type metric hex bit? Has the inside of the set-screw damaged yet? If you happen to have one of the metric hex bit sockets that you use on a 3/8" ratchet wrench, before you try to loosen it, fit the hex bit into the set-screw, and give it a few taps on the drive end of the socket bit. Then give it a try to see if it will break loose, if not tap on the top again, this is to really make sure it is seated in the set-screw, but it can also help loosen them up. Before you try to loosen it again, give it just a slight amount of tightening torque, then try to loosen it. Many times, if you tighten a little, it is enough to break it free, then you can back it out. Most of the problematic set-screws that I have seen on the coupler, is that a lot of them have actually worked loose, instead of being frozen in place. Hope this help. Good luck!! Tony.

[Mitch Leland]

One more little tip.... This is particularly good for stripped out Phillips head slots, use a dab of valve grinding compound on the tip of your screw driver. I'm sure it would help with your alan set screw as well, it's really magic...

[toddu]

+ 1 for 3.2 CAB

I changed my last winter, and it was very frozen. I was just about to drill it out and through f--- it, I'll give it one last try. At this point I was very pissed, and tried with all my might, and it broke free.

I would try it again with the proper tool (too much flex in those L shaped allen wrenches) before you bugger it up.

Todd

[ChrisBennet]

Originally Posted by 450knotOffice

I'd say drill it and use one of those fastener removal tools that they have at Sears. They're pretty cheap and are basically little tapered and hardened studs with sharpened serrated edges that will basically cut into the sides of the hole you drilled into the fastener and wedge themselves in. Then all you do is attach a socket wrench and unscrew it. The harder you turn it, the deeper into the fastener it wedges itself, so it won't "strip" out.

In my experience, one of those tools (EZ-out I think they're called) is, as a friend of mine put it:
"A tool for replacing a difficult to remove bolt with an impossible to drill out EZ-out".
Translation, they tend to break off in the hole and then you're really hosed.

-Chris

[3.2 CAB]

Maybe we will hear an update from MIK911.

Chris, I too, have seen many items brought to me, that had an EZ-out, shattered off inside the bolt/stud/set-screw, etc. Over the years, I actually found that I had really nice outcomes with the left-handed drill bits. I found them especially useful when used with my 18volt DeWALT hammer drill, in the low speed range, with the hammer mode selected. I have found very few that I have had to use more than just that type of drill and the left hand bits.

toddu, I have been to "Queen City" many times, before I retired. Very nice place!! Tony.

[mhoffman]

I'd be hesistant to drill it out- it is tapered and get the new one to fit tightly might be problematic. If "mechanical aggitation" does not work, perhaps a bit of heat?

[3.2 CAB]

Matt, that set-screw is one of the oddest looking set-screws that I have seen, even in non-Porsche applications. It is a severely tapered set-screw. If I remember correctly, the contact area, is about half the size of the "head" of it. Sort of like looking at a tiny tornado from the side. I too, would not drill it. Tony.

[Mitch Leland]

I agree with Chris, especially in the smaller sizes. I think the e-z out just puts a lot of pressure on the sides of the screw making it all the more difficult to remove.

Also we forget too often about tapping on the bolt. If you have ever had a part in a press with a lot of hydraulic pressure on the part you're trying to remove, then tap the part with a hammer and often if will release itself with a loud bang.

The left hand drill is a great idea...

[mhoffman]

Before giving up and destroying it, try a couple of heat cycles with Kroil or PB- might save you buying a new shaft...

[khamul02]

Great point. I failed to mention I use PB blaster as well.

[mhinch]

MIK911,

I had a similar problem that you are experiencing, but the allen stud was already rounded on the inside by the previous owners attempt to remove it. I tried grips PB blaster and a little heat from a mini propane gun but to no avail.
I resigned myself to the fact that I was about to buy a new coupler, so armed with a drill and a 6 mm drill bit I started drilling straight down the centre of the allen stud. Allen studs are harder than normal bolts due to the manufacturing process, but will still drill ok with carbide drill bits. Once I generated some heat by drilling I used a pair of grips and to my amazement (and luck) the taper had freed itself and unsrewed easily. On closer inspection its the taper that seizes, (just like on a motocycle engine flywheel,) the thread on serves to push the taper into the hole. Try shocking the coupler with a hammer and small blunt chisel close to the gear box shaft, it may free the taper, then as already mentioned use a 3/8" ratchet and a allen key drive to get better leverage than an allen key.

hope this helps

Mark

[rusnak]

you might have the 1986-only reverse thread setscrew. Just kidding. +1 on "PB Blaster". Napa Auto has it. I'd also use an allen ratchet driver, but a hardened one like the ones made by Craftsman or Lisle. Otherwise you might be screwed.

[RoninLB]

Originally Posted by Mitch Leland

, use a dab of valve grinding compound on the tip of your screw driver. ...

i thought i was the only one keeping that stuff around.

Cheap enough and in a small container.

[MIK911]

SUCCESS!!!---thanks all.
I used a combination of above mentioned techniques. Used PB blaster overnight, whacked the set screw a couple times with a chisel, and most importantly, used the hex socket rachet (as opposed to "L" allen wrench), as 3.2Cab recommended. Crazy part was, I have a set of those hex sockets, but forgot about them 'till 3.2cab mentioned it.

"Valve grinding compound"--for future reference, what is this? Is it an abrasive that allows the screwdriver/tool to get a better grip on the screw? Is it a putty-like material? HomeDepot sourced?

Thanks again to everyone. Now onto the 'real' job at hand--changing the shift coupler bushings.

[MIK911]

Originally Posted by rusnak

you might have the 1986-only reverse thread setscrew. Just kidding. .

You laugh, but I yesterday, I was seriously wondering.........

[RWebb]

Congrats!

"Valve grinding compound" = abrasive used to grind valves* - often blue; get it at auto parts house

*back in the old days, people used to do this themselves - esp. on the old Detroit iron, which had clearances with about the same fit as a .45

[3.2 CAB]

Glad you got it out!!! You should not have too much trouble changing the bushings out. Are you using factory or after market bushings?

Ditto, on what Randy said about the compound. I use it extensively in gunsmith work, particularly, when fitting custom barrels and bushings on a 1911A1 .45ACP or National Match Colt.