2002 Chevrolet Silverado with 5.3.
Found a couple of the exhaust manifold bolts had the head broken off. Unfortunately the drivers side rear bolt is broken at the head. No room to get an angle drill in there. I’m assuming the only way to fix it is to take the head off?
DT
weld a nut on it. Part of the stud should be showing when you take the manifold off.
You are probably right, that you will need to take the head off.
if you can put a nut over the broken stud and weld the broken stud to the nut through the hole in the nut it may come off. I do not know how much room you have to know if that is feasible. It is not a sure-fire, workes every time. But it is by far the best DIY option. The key is to put a lot of heat into the stud.
I restore OLD tractors that have manifold studs broken. On the positive side, mine are probably more accessible. But mine have been in place for 70+ years. So if you can get a welder to it, the chance to succeed is pretty good. There are 101 youtube videos showing this technique.
The rear one actually broke flush if not a little recessed into the head. I changed the other broken knew out. I’m going to try and have someone get some weld on it before I actually pull the head. Luckily the broken one on the passenger side went easy. I removed two broken on the drivers side. Just have the flush one left.
DT
A trick a mechanic showed me was once you get it hot to melt some bees wax on it , the heat will suck the wax in and lubricate the threads. It worked on a broken exhaust bolt on my atv.
no need to pull the head on that motor,if you have access to a right angle drill get yourself a 5/32 left hand drill bit.
I have had very good luck having the bit “stick” in the hole and back the broken bolt right out.
if that doesnt work,using a 5/32 drill bit,drill clear through the back of the stud until you feel the bit pop out of the back of the bolt.
using a wire welder fill the hole back in and keep welding out towards yourself until you have a little knob sticking out from the stud.
( the heat from welding will shrink the bolt and loosen it from the thread )
place a flat washer onto the knob you made and weld the flat washer to it.
place a 3/8 ( 9/16 wrench ) nut on the washer and weld the nut to the washer,the washer gives you a bearing surface against the head and the nut will not dig into the head.
back the broken stud out.
on real stubborn ones,it may take three or four tries,I have never had to remove a head for this type of job on any brand.
dont worry about messing up the surface of the head surrounding the bolt,you can only do that if you miss welding the bolt and keep the arc on the aluminum,if you see that happening,quit and reprosition where you are welding and start again.
Thanks all.
DT
no need to do the angle drill bit….dorman makes a little bracket that bolts on and will apply pressure to the exhaust manifold and seal it right up. just google dorman exhaust manifold bracket for 5.3l….i have used them a couple times when customers want it done as inexpensive as possible and have had zero problems with them and they are super eaasy to install…hope this helps
Very interesting. Thanks.
DT
no need to do the angle drill bit….dorman makes a little bracket that bolts on and will apply pressure to the exhaust manifold and seal it right up. just google dorman exhaust manifold bracket for 5.3l.
This.
My old Silverado had a center and a rear clamp installed. Both are easy peasy, specially compared to bolt extraction…
Looked on the Dorman website. Says they make them for the rear left and front right. My broken bolt is on the drivers side next to the firewall. Is that considered rear left? Sitting on the car looking forward?
DT
Looked on the Dorman website. Says they make them for the rear left and front right. My broken bolt is on the drivers side next to the firewall. Is that considered rear right? So they don’t have one for my need?
They make 3 different clamps. 917-107 Should be rear left. Front left is the same as the rear right and front right is the same as the rear left (confusing, I know). Then they make a center clamp. That’s actually the most commonly broke bolt…
Thanks. Got it ordered. I had a total of 4 broken bolts. Got all out except the back one. This should solve my problem. 
DT
Thanks. Got it ordered. I had a total of 4 broken bolts. Got all out except the back one. This should solve my problem.
DT
Be sure to follow the torque spec Dorman lists as I believe the mounting bolts are torqued much higher than the clamp bolt.
Got the bracket installed, barely. They don’t leave much room between the heads and the firewall. I was only able to tighten them with a ratcheting wrench. No way I could get a torque wrench or even a ratchet in there.
DT
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