Snapped Intake Bolt
Thread Starter
Intermediate
Joined: Jul 2013
Posts: 30
Likes: 0
From: Pittsburgh PA
Snapped Intake Bolt
While changing the water pump on my 78 L82 this weekend I had to remove the smog pump bracket. It's held on by a water pump bolt and the forward most intake manifold bolt on the passenger side. I ended up snapping the manifold bolt trying to remove the bracket.
I'm going to attack it this weekend with an easy out after soaking all week with penetrating oil. My question is, if I'm not successful and have to drill the bolt out, is the hole blind?
I'm going to attack it this weekend with an easy out after soaking all week with penetrating oil. My question is, if I'm not successful and have to drill the bolt out, is the hole blind?
2026 Loser of the Year
Joined: Sep 2013
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From: New Or-leens Loo-z-anna
Try wrapping some masking tape around the drill (bit) 1/2" from the tip...stop drilling when the "bit" is deep enough to touch the tape on the broken bolt surface......then try using the easy out.
Le Mans Master
Joined: Jan 2006
Posts: 6,504
Likes: 139
From: Butler Pa
I hate ez outs. They break and then you're really screwed.
First, try a left handed drill bit. Many times it will grab and unscrew the broken piece right out. If that doesn't work try the ez out but be very carefull.
I could very well be wrong but I think the end intake bolt holes are blind.
First, try a left handed drill bit. Many times it will grab and unscrew the broken piece right out. If that doesn't work try the ez out but be very carefull.
I could very well be wrong but I think the end intake bolt holes are blind.
Drifting
Joined: Jan 2011
Posts: 1,853
Likes: 81
From: Hamilton Virginia
Spray the broken with lube every so often and let sit. Try it to use a pic at the broken edges. I have actually gotten a couple bolts loose by trying to turn them with a pic after soaking them. If that doesnt work drill a very small hole in the middle of the broken bolt, and just keep using bigger and bigger bits till you are as close to the threads as possible. then use an easy out. all the vibrating of the bit drilling help loosen it up.
Melting Slicks
Joined: Feb 2003
Posts: 2,330
Likes: 6
From: Long Island NY
Something happened to my '78 L-82..broke both front bolts (they go into the water jacket). They were broken flush. This may sound nuts, but it worked for me. If it is the front bolt(s) only...I picked the back of the manifold up (since it's aluminum it's easy to do). Just a little rocking up & down...it took some time but the manifold came off with no damage anywhere. Then I had the rest of the bolt to get out...
Safety Car
Joined: Jun 2004
Posts: 4,363
Likes: 221
From: Beecher Illinois
Something happened to my '78 L-82..broke both front bolts (they go into the water jacket). They were broken flush. This may sound nuts, but it worked for me. If it is the front bolt(s) only...I picked the back of the manifold up (since it's aluminum it's easy to do). Just a little rocking up & down...it took some time but the manifold came off with no damage anywhere. Then I had the rest of the bolt to get out...
They are not stuck into the head but to the manifold. You need to break that seal like mentioned in this post. Then those bolts will screw right out.
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Thread Starter
Intermediate
Joined: Jul 2013
Posts: 30
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From: Pittsburgh PA
The problem is the bolts at the front and rear of the intake manifold go into the water passage and seize to the aluminum intake.
They are not stuck into the head but to the manifold. You need to break that seal like mentioned in this post. Then those bolts will screw right out.
They are not stuck into the head but to the manifold. You need to break that seal like mentioned in this post. Then those bolts will screw right out.
Team Owner
Joined: Jul 2004
Posts: 40,338
Likes: 786
From: Redondo Beach, California
I hate ez outs. They break and then you're really screwed.
First, try a left handed drill bit. Many times it will grab and unscrew the broken piece right out. If that doesn't work try the ez out but be very carefull.
I could very well be wrong but I think the end intake bolt holes are blind.
First, try a left handed drill bit. Many times it will grab and unscrew the broken piece right out. If that doesn't work try the ez out but be very carefull.
I could very well be wrong but I think the end intake bolt holes are blind.
Left handed drill bits usually have to be bought from a machinists supply house. They are not generally available.
Also, if you can get a "bite" into the bolt with a reverse tap...USE AN AIR POWERED IMPACT WRENCH. They impacts are much more forceful than a slow steady torque from a manual wrench.
..............
Just for general interest for the community...there is a machine shop that specializes in ONLY broken bolts and damaged threads. It's Jerry's Tap and Die in Santa Ana, California. They remove broken bolts with electric discharge erosion in their facility. They also travel to field sites. Their main customers are operators in the heavy machinery and oil/gas industries. I've seen automobile and aircraft engines in their shop for broken bolt removal. I've had them repair threads on GM aluminum bellhousings
Intermediate
Joined: Jul 2014
Posts: 26
Likes: 25
I've had some luck with broken bolts by first soaking them in Liquid Wrench a few times over a few days. Each time, I'd take a center punch/hammer and tap it lightly dead center. Even if you have to drill, you're better off center punch a starter hole anyway. The combination of the lube and shock vibration will help "unstick" the seized threads.
Also, you can try creating a small hole/dent off to the side of the face of the bolt, then using your center punch/hammer, try tapping it counterclockwise to back it out a bit.
Good luck!
Also, you can try creating a small hole/dent off to the side of the face of the bolt, then using your center punch/hammer, try tapping it counterclockwise to back it out a bit.
Good luck!
Le Mans Master
Joined: Jan 2006
Posts: 6,504
Likes: 139
From: Butler Pa
http://www.amazon.com/s/ref=nb_sb_no...%20drill%20bit
I can also walk into most any hardware store around here and buy them.
Also, if you can get a "bite" into the bolt with a reverse tap...USE AN AIR POWERED IMPACT WRENCH. They impacts are much more forceful than a slow steady torque from a manual wrench.
Le Mans Master
Joined: Jul 2006
Posts: 8,117
Likes: 104
From: charlotte north carolina
That is a blind hole. The situation is that the bolt is broken off below the surface of the manifold, but above the head? Forget about Easy-outs. That bolt is corroded to the head tightly enough to snap the head off, the puny grip that a bolt extractor has isn't going to move it. You'll have to drill it out. The trick is to flatten the end of the bolt so that a small guide bit doesn't drift off center of the broken bolt. Use a dremmel at high speed and oil with a small end cutting bit to flatten the center.
Melting Slicks
Joined: Jun 2006
Posts: 2,071
Likes: 147
From: S Nevada
Heat. Borrow or rent a small oxy acetylene torch. I'm pretty sure you will have better luck if you can remove the intake as mentioned earlier. You then may have enough bolt exposed to get on it with a stud remover, if not, left hand drill or ez out. Heat the area surrounding the broken bolt. Shoot some more of your penetrating oil on the bolt, then give it a go. Rarely will it not come out. Your simple water pump change just turned into a can of worms. So do it right. Stud removers are wonderful little tools if enough of the bolt is exposed, but If you have to drill, grind the bolt flat and use a punch to mark the center.