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B5244 broken head bolt.

M

marx3

New member
Joined
Aug 21, 2011
Location
Denmark
I got a B5244 with a snapped head bolt... How would you suggest I pull this guy out?
The threads are positionen pretty far down the bolt hole in the block, I guess it sits about 2 inches down.
I guess a links tap would be the way to go.
Has anybody tried this before?
 
Just drill on center as best you can (or better yet buy or make a drill guide bushing) and use an Easy Out. They come out really easy... This is very common issue. I use a reverse rotation drill bit, and often times they just spin out with that alone!
 
+1

Had the same on a b6284. Center punch, some heat to the side of the block, good penetrating oil (no wd40, get some real stuff, like the stuff from wera). Drilled a 5? Mm hole in it and used one of those simple tapered left hand threading taps. Came out easily.
But be careful with those reverse taps, they break easily.

If nothing works and you can get the block out of the car, go to a firm that does injection mold making. At work we regularily remove all kinds of broken bolts from molds with edm machine.
 
Pull the block and have a machinist save your ass. I had to do that on a red block once...
 
marx3 said:
I got a B5244 with a snapped head bolt... How would you suggest I pull this guy out?
The threads are positionen pretty far down the bolt hole in the block, I guess it sits about 2 inches down.
I guess a links tap would be the way to go.
Has anybody tried this before?
Click to expand...

ZVOLV said:
Pull the block and have a machinist save your ass. I had to do that on a red block once...
Click to expand...

2 inched down presents a major problem for anyone, even the experienced. Weigh the cost of the block vs. the hassle of R&R against the probability of ANYTHING going wrong.
 
I busted one once. I wound up spraying some PB down in the hole and let it sit for a day or so (this may not have actually been needed, since it wasn't really corroded)

Stuck a piece of steel rod down there and whacked it with hammer a few times to try and shock it loose, then got REALLY lucky with a left-handed drillbit and an EZ-Out. Mine was only about 3/4" below the deck surface though. Ymmv.
 
Even with professional tools, that is a VERY risky endeavor. If you mess up its not something you can just Helicon or oversize. If you go at it with some home Depot drill bits and some harbor freight extractors, I bet failure will occur!!! Head bolts are strong metal. And if you break off a bit or extractor, or drill off center you are boned. The fact that you started a thread asking about it, no offense, means it's probably beyond your tool and skill level. I have a machinist that i pay $15 to pull busted hardware and I have been known to pull a b230ft head or two and bring it to him with busted studs. Drilling with a head or engine in place is always risky but sometimes you can get lucky.
 
Let us not forget, this is an ALUMINUM Block, so the reasons for it getting stuck can differ from a cast iron block. Unless you can afford the risk, machine shop time... Call around and describe the situation, find one that you can trust.
 
If? you can. I've welded a nut to the broken bolt,stud, the heat of welding sometimes will loosen the part and with the hex you can back it out. Good luck. Sometimes with aluminum the weld causes the bond to break, Have removed many stuck/broken fasteners this way for machine shops.
 
If it's 2" down in the block/ how much stud is left? 2" thread engagement should be plenty to use for a new stud. If that far down, drill with the proper drill for the thread root and use a taper tap to clean the hole followed by a bottoming tap.I'm not sure what we are dealing with here?
 
ZVOLV said:
Even with professional tools, that is a VERY risky endeavor. If you mess up its not something you can just Helicon or oversize. If you go at it with some home Depot drill bits and some harbor freight extractors, I bet failure will occur!!! Head bolts are strong metal. And if you break off a bit or extractor, or drill off center you are boned. The fact that you started a thread asking about it, no offense, means it's probably beyond your tool and skill level. I have a machinist that i pay $15 to pull busted hardware and I have been known to pull a b230ft head or two and bring it to him with busted studs. Drilling with a head or engine in place is always risky but sometimes you can get lucky.
Click to expand...

Z said it best..
 
It will just come right out, EASY. A F'n strong ass magnet might even be enough to spin it out of there. It is more common for at LEAST one bolt to break off when pulling the head, than not.
 
Boy am I glad several if you guys have tried this before.
The threaded part of the bolt hole sits about 2 inches below block deck. I suppose any 5 cylinder is that way.
Being these are blind holes, I guess the reason for the snap is not corrosion, but simply just stress. That stress is released once the bolt is loosened ( or snaps )
The head bolts themselves have threads on a big portion of them, but really only the lower 2 inches of the bolt needs to be threaded.

I bought a set of left hand thread bolt extra actors and will drill a pilot hole very carefully.
 
marx3 said:
Boy am I glad several if you guys have tried this before.
The threaded part of the bolt hole sits about 2 inches below block deck. I suppose any 5 cylinder is that way.
Being these are blind holes, I guess the reason for the snap is not corrosion, but simply just stress. That stress is released once the bolt is loosened ( or snaps )
The head bolts themselves have threads on a big portion of them, but really only the lower 2 inches of the bolt needs to be threaded.

I bought a set of left hand thread bolt extra actors and will drill a pilot hole very carefully.
Click to expand...

You'll get it! And, yes, it snaps off from the "shock" of snapping loose.

Cheers
 
ZVOLV said:
Even with professional tools, that is a VERY risky endeavor. If you mess up its not something you can just Helicon or oversize. If you go at it with some home Depot drill bits and some harbor freight extractors, I bet failure will occur!!! Head bolts are strong metal. And if you break off a bit or extractor, or drill off center you are boned. The fact that you started a thread asking about it, no offense, means it's probably beyond your tool and skill level. I have a machinist that i pay $15 to pull busted hardware and I have been known to pull a b230ft head or two and bring it to him with busted studs. Drilling with a head or engine in place is always risky but sometimes you can get lucky.
Click to expand...


Hi Zvolv, glad to see you're alive. Pm me, will ya...
 
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