Stuck Connecting Rod Screw

[wolfden793]

Hi All,

I have a Briggs 12000 series engine that I'm tearing down for rebuild and can't remove one of the screws attaching the connecting rod to the crank. One came right out, but the one closest to the piston is a bit longer and I've tried everything I can think of the remove it with no luck. I had this happen one other time, but eventually got it out. I tried heat, longer handled tools for torque, vice grips, no soap. It's easily accessible, just won't budge. It's a steel screw in an alluminum block, so I don't want to strip it. Any suggestions would be appreciated!

 

[ROUSTABOUT]

Put a wrench on it and tap wrench with a hammer. Just tap on it, don't beat the crap out of it.

 

[wolfden793]

Put a wrench on it and tap wrench with a hammer. Just tap on it, don't beat the crap out of it.

Hi There,

Thanks for the reply. Been there, tried that. Nope.

 

[ROUSTABOUT]

Hi There,

Thanks for the reply. Been there, tried that. Nope.

Take a propane torch and heat the part it is threaded into. May have locktite on it and heat will release it. I'd tap it too.

 

[wolfden793]

Hi Again,

Yup, tried this also. I did tap it when I heated it. I thought the same thing about the thread lock. Probably what's causing it.

 

[5030]

Impact wrench set on reduced power...

 

[wolfden793]

I wish I could get my impact in there, but not enough room. I need to buy a small air powered one that gets into tight spaces. Thanks for the suggestion.

 

[flyerdan]

I've used an air hammer in similar situations; grind a semi circle in one of the chisels so it fits around the socket, or extension. Put some hand tension on it and give a few short blasts, you should feel it start to move. Doing it that way eliminates pulling the threads out because you're not throwing massive torque into the rotation.

 

[wolfden793]

I don't have an air hammer, but you've given me some ideas. If I used my Dremel and cut a slot into the head of the bolt and then use a chisel to apply torque to the slot, maybe that will begin to move it. Thanks for your suggestion.

 

[flyerdan]

I did a 12000 earlier this year and have a spare tore down in the shop, if I recall it is a 5/16 head 10-32 bolt. I didn't have any issue getting mine apart. Worst case, grind the head off so you can get the rod out and deal with the stub in a vise.

 

[wolfden793]

Hello,

Thanks for your response. Yup, sounds right. Grinding the head may be a good solution. Should be easy with my dremel.

 

[Tinhack]

It can't possibly be that tight. Use a 6-point socket and rachet. Are you sure you're trying to turn the right way. It is upside down you know.

 

[wolfden793]

Hello,

Thanks for your response. Yup, sounds right. Grinding the head may be a good solution. Should be easy with my dremel.

Got it! Thanks everyone for their ideas. This is what I came up with. Using my dremel and a composite cutting wheel, I cut a slot into the head and then using a flat punch and hammer, pushed down on the edge of the cut and it came free almost immediately! Got plenty of spare bolts so back in business! Thanks again!

 

[wolfden793]

It can't possibly be that tight. Use a 6-point socket and rachet. Are you sure you're trying to turn the right way. It is upside down you know.

Believe me, it was! I did use the ratchet and six point with no success. The other one came out easily. I thought about the upside down position, but I was turning the correct way. Thanks for your input!