Best Way To Remove Broken Timing Cover Bolt

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

carnerd3000

Newbie
Joined
Feb 6, 2022
Messages
25
Reaction score
28
Location
Northeast USA
So I'm working on the timing cover and the intake manifold gaskets on my Suburban, and since last week I got into a jam regarding one of the new bolts to the new timing cover breaking off due to being overtightened. I was trying to do the torquing to spec, which is supposed to be 106 in/lbs., but it turns out the torque specs may have been too much. That or the bolts themselves weren't up to par to handle the torque specs. Anyway, 4 of the bolts broke inside the block while I was tightening (and unfortunately I didn't figure that out on the first one I broke :p) and I was able to get out 3 of them by kind of unscrewing them out with an awe. The last one was coming out, but then it became difficult as it became flush with the screw hole, and then it became hard to spin it out with the awe, and I believe it's because I can't get a good angle on it with the PS pump bracket in the way. I also did try drilling it out, but all it really does is just scrape away the bolt, and not exactly drill through it. I don't know if my drills aren't fast enough, or if the bits aren't hard enough against the bolt.

With that being said, my next plan was to get some cold chisels and then kind of crack the bolt free. Is this an okay idea, or should I do something else? And if it's possible, I was wondering if anyone could tell me what the material of the timing cover bolts are. I got the Dorman timing cover number 635-505. Maybe I should get harder drill bits too?

You must be registered for see images attach
 

stutaeng

I'm Awesome
Joined
Aug 7, 2019
Messages
3,410
Reaction score
4,348
Location
Dallas, TX
Yikes! Not good! :(

Can you weld a nut on the broken piece. Is that cover is plastic? If so, the heat/sparks will probably ruin it.

Did you clean the threads? maybe some gunk got in there and that's why the new bolts had trouble going in? Rust maybe? At this point, anything that works to get the broken bolt out is fair game. Heat is probably your friend here.
 
Last edited:

SAATR

/\___/\___/\___/\___/\
Supporting Member
Joined
Dec 16, 2010
Messages
2,649
Reaction score
938
Location
Loo E Z an uh
Pull the cover and the power steering pump bracket off to give yourself as much room as you need, and reevaluate. A small, sharp chisel will likely motivate the bolt the rest of the way out, just like the awl did.
 

carnerd3000

Newbie
Joined
Feb 6, 2022
Messages
25
Reaction score
28
Location
Northeast USA
I have a ft/lb. wrench, and I set it to 9 ft/lbs. When I used a calculator to figure out the conversion, it came to 8.83, so I rounded up to 9 ft/lbs. And if I use the left-hand drill bit, is there a certain material bit I should use, or just anyone from a hardware store will do?
 

1998_K1500_Sub

Nitro Junkie
Supporting Member
Joined
Jan 28, 2019
Messages
1,983
Reaction score
2,992
Location
Rural Illinois
I have a ft/lb. wrench, and I set it to 9 ft/lbs.

If it's one of those 10-75 lbft wrenches, then "well,... OK", if it's one that goes to 150 lbft, not so much.

Better to use an lbin wrench, but perhaps you already knew so and, regardless, it's behind you now.

I still can't fathom breaking any of those bolts, but... I just checked and a Grade 5 1/4-20 spec is ~90-100 lbin
 
Last edited:

SAATR

/\___/\___/\___/\___/\
Supporting Member
Joined
Dec 16, 2010
Messages
2,649
Reaction score
938
Location
Loo E Z an uh
I have a ft/lb. wrench, and I set it to 9 ft/lbs. When I used a calculator to figure out the conversion, it came to 8.83, so I rounded up to 9 ft/lbs. And if I use the left-hand drill bit, is there a certain material bit I should use, or just anyone from a hardware store will do?

Torque wrenches tend to be much less accurate at the extreme low end of their range. I'm guessing that this is a 3/8 drive, 10lbft to 80lbft set to 1 notch below 10? If so, you may not have even felt the click. I've had that problem trying to use a wrench at too low a setting.
 
Top