stripped allen bolt

[new welder guy]

hello im trying to rebuild a gear box on my semi that runs off my pto to drive my pump. I have 2. 5/16" size allen bolts that have stripped out trying to remove them. they are in very tight could not get vis grips to lock on and turn them there is no room. what is there to get them out, i though about welding a bolt into them and using a shocket to remove them or grind the heads off and try to remove them that why the bolts are about 2.5" long

[Hotfoot]

Are you sure they were 5/16", and not Metric (which might be why you stripped them)?

I'd tap a stub of Allen hex in there, the kind that a socket slips over (like my Craftsman Allen 3/8" sockets), give it a short weld right at the bolt, then slip the socket over and wrench it out. The heat from the weld should free the bolt.

[new welder guy]

pertty sure got all the others out find these to was rusted in and i could not get them with a braker bar so i used my impact on a allen shocket which was just alittle more then the head of the bolt could take after the last builder over tighted them to 200 + foot pounds

[chevysant]

If you have an air hammer, put a good chisel on it and hit top of the head at an angle. That should break it loose, if space allows.

[SidecarFlip]

A shot in the dark....

You say semi, so I presume you have a wet kit on your tractor and we'll presume it's a diesel and also presume it has some model of RoadRanger (Eaton) transmission. If so, the PTO drive is on the side, secured by 4 bolts that should have been hex capscrews, not socket head cap screws (aka allen head). If you twisted the heads off you should still be able to remove the pto drive casting and then weld on the end of a hex capscrew and back out the broken bolt shank. Welding on the top of a hex capscrew will loosen the stud via the weld heat, allowing you to back out the broken bolt.

Don't forget to set the preload when you put it back together.

Just being presumptious.................

[Scott Young]

you could clip a tiny piece of bronze and some flux in the hole and then place the allan wrench on it. heat allen head till bronze liquidfies. let cool and then turn remove bolt.

on the bigger allen wrenches, it won't bond to the wrench due to the wrench not getting hot enough. The bronze will bond to the allen bolt because it is hot enough. you now have a perfect fit and most of the time you won't have to sacrifice a good allen wrench.

[whateg0]

you could clip a tiny piece of bronze and some flux in the hole and then place the allan wrench on it. heat allen head till bronze liquidfies. let cool and then turn remove bolt.

on the bigger allen wrenches, it won't bond to the wrench due to the wrench not getting hot enough. The bronze will bond to the allen bolt because it is hot enough. you now have a perfect fit and most of the time you won't have to sacrifice a good allen wrench.

Scott, that's a neat idea! I'll tuck that away for when I need it.

Dave

[Thomas Harris]

a punch or chisel whacking the bolt head ccw will loosen some really stubborn stuff. Get it good and sharp so it digs into the head for a solid impact. I always try this first if possible, as it has no chance for heat damage to anythng, and usually is availible with the tools directly at hand.

[new welder guy]

A shot in the dark....

You say semi, so I presume you have a wet kit on your tractor and we'll presume it's a diesel and also presume it has some model of RoadRanger (Eaton) transmission. If so, the PTO drive is on the side, secured by 4 bolts that should have been hex capscrews, not socket head cap screws (aka allen head). If you twisted the heads off you should still be able to remove the pto drive casting and then weld on the end of a hex capscrew and back out the broken bolt shank. Welding on the top of a hex capscrew will loosen the stud via the weld heat, allowing you to back out the broken bolt.

Don't forget to set the preload when you put it back together.

Just being presumptious.................

yes you are right about the truck. but its not my pto its my gearbox that my pto runs. i have a gearbox to make a 90* turn to my vaccum pump from the pto. what i ended up doing is welding a bolt to and got it out and the other i had to cut the head of the bolt off to take the load off it to turn it out

[SidecarFlip]

Ah, you have an air can. Of course you have a big black rubber mallet too.

I work on wet kits ocassionally (we have 2 tractors with wet kits for roll off's).

You still need to loose the socket head capscrews and replace them with high strength hex caps. Recessed hex caps have no place on a working truck. They fill with crud and are a PITA to work with.

[new welder guy]

x2 all bolts on trucks should be hex head bolts like you said allens have no place in a work truck they just dont stand up to the needs of the job

Ah, you have an air can. Of course you have a big black rubber mallet too.

I work on wet kits ocassionally (we have 2 tractors with wet kits for roll off's).

You still need to loose the socket head capscrews and replace them with high strength hex caps. Recessed hex caps have no place on a working truck. They fill with crud and are a PITA to work with.

[vicegrip]

In concept I understand, the point of the two previous posts.
It's common sence, realy.
BUT:
To clear up one thing.
Should any of you ever have a project that has an unusual bolting issue,
quallity S.H.C.S.'s are every bit up-to a mounting challenge
as far as strenght etc. goes.
=========
Remember two things....
1, If the application is in a harsh environment,
Clean and fill the hex socket and the Counter'bore around each head
with a high quallity R.T.V. or equiv.

2, With socket head cap screws, (removal) you get one chance only.!!!
If U use a rounded allen wrench of don't get it seated in the hex
ALL THE WAY, you deserve the ensuing problem.

vg

[SidecarFlip]

Vice Grip....

I understand your point entirely and I prefer SHCS fasteners on machine tools, that's the industry norm, at least for quality machinery but on a truck, HCS is better from a removal/replacement standpoint with spline drive coming in second.

[texcowman50]

If all else fails you can drill the heads off and slide your part off then take the studs that are left out with vise grips or pipe wrench. If the are 5\16 bolts use a 5\16 or 11\32 drill and drill in the center untill the head comes off.

[JoeS]

one method we use alot, especially with TORX bolts on GM applications (they use them to bolt engine front accessories on that are gawd-awful tight), take a punch, and wail on that bolt head straight in with a big hammer(eye protection!). this impact slightly compresses the material being bolted together, as well as shocks the threads, and the bolts will usually get very loose and then are easily removed.

we use this method on the TORX bolts because the TORX drivers are very weak, and we have snapped them off prior to using this method.