Broken Valve Cover Stud - tried everything what to do now? (1 Viewer)

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Just nut it from underneath. The factory bolt is M6 x 1.0 x 25mm, you'll need one a bit longer.

Amazon product ASIN B07W6JYTYL
I don't care for the factory bolts either, too soft.
 
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6x1.00mm timesert = back to original.


Agree with making a proper fix, it's just such a hard spot to work in. Might be better to wait until the head needs to come off.
 
It might not be too hard. The only power tool involved at this point would be drilling to the proper size, the rest of the kit supplied tools are hand tools.
 
If you go with the longer bolt, make sure that it is either fully threaded or the shank is not too long to bottom out in the threads before the VC is seated.
 
To keep all the valve cover bolts the same size, I would use the Helicoil. Also add anti-sieze to the bolts when you put them back in to prevent this from happening again.
Second choice and cheapest would be to use a longer M6 bolt with a nut. It is in a fairly accessible location.
LOL< Fairly accessible. I get what you're saying but it sure didn't feel very accessible trying to get the broken stud out.
It might not be too hard. The only power tool involved at this point would be drilling to the proper size, the rest of the kit supplied tools are hand tools.
Yeah, the kit I bought requires it to be drilled out with a 1/4" hole for the Helicoil tap. I don't think I have 1/4" bit stubby enough to get in there...I'd have to cut one down, and I'm not sure if chucking up the bit on threads would work very good.
 
I hate rigging things but, in this case, I would wait until the heads come out for a head gasket so you can make a proper repair. Just through bolt it for now and call it a day. You already, more than likely, have accidentally dumped some metal, albeit small, into the engine assembly. Just wait, this is not a critical part, why bugger it up even more? Wait till you have the room and easy access to do it right.
 
I hate rigging things but, in this case, I would wait until the heads come out for a head gasket so you can make a proper repair. Just through bolt it for now and call it a day. You already, more than likely, have accidentally dumped some metal, albeit small, into the engine assembly. Just wait, this is not a critical part, why bugger it up even more? Wait till you have the room and easy access to do it right.

Agreed
 
Another vote for "nut from back side", then helicoil when the head comes out for HG in future.

Your patience is commendable.
 
Thanks guys. I'm taking your advice and just going to nut it from the underside. I put my 1/4" drill bit in the vice and was ready to take the cuttoff wheel to it to cut it down in order to drill the head out for a helicoil and just couldn't bring myself to do it. Even if I can get it drilled out nice and straight, trying to get it tapped and a helicoil in there is just more opportunity for things to go awry. The perfectionist in me hates this jury rig approach, but I think it's for the best. As long as my valve cover is seated good and not leaking, I guess mission accomplished.
 
Thanks guys. I'm taking your advice and just going to nut it from the underside. I put my 1/4" drill bit in the vice and was ready to take the cuttoff wheel to it to cut it down in order to drill the head out for a helicoil and just couldn't bring myself to do it. Even if I can get it drilled out nice and straight, trying to get it tapped and a helicoil in there is just more opportunity for things to go awry. The perfectionist in me hates this jury rig approach, but I think it's for the best. As long as my valve cover is seated good and not leaking, I guess mission accomplished.


Smart man. Like you, I like for things to be 'right'...but owing to circumstance, its more likely something will go wrong than right if you continue. It can be fixed correctly later. I admire your perseverance....but better to wait on this one.

You've already suffered a string of bad luck: Bolt breaks off in head, bolt will NOT turn and continues to break off, bolt has to be the ONE waaaay in the back all crowded up against the firewall.
 
I just experienced the exact same thing two weeks ago, same bolt head just snapped off. It took me three days of praying and talking ugly to finally get it out. Luckily the bolt didn't break off. I used PB Blaster for three days, shocking it with hammer tapping, and clamping vise grips on it, but it would not budge, Finally was able to drive a Craftsmen bolt/stud remover down over the bolt shank and used a 1/4" ratchet and socket to break it loose. When it finally popped and broke loose I though the stud had snapped off level with the head. I could not believe that that small of a bolt could be so tightly frozen.
 
I just experienced the exact same thing two weeks ago, same bolt head just snapped off. It took me three days of praying and talking ugly to finally get it out. Luckily the bolt didn't break off. I used PB Blaster for three days, shocking it with hammer tapping, and clamping vise grips on it, but it would not budge, Finally was able to drive a Craftsmen bolt/stud remover down over the bolt shank and used a 1/4" ratchet and socket to break it loose. When it finally popped and broke loose I though the stud had snapped off level with the head. I could not believe that that small of a bolt could be so tightly frozen.
I wonder if it's something about being back there right against the firewall and above the exhaust that it gets hotter than the other bolts and therefore seizes up somehow.
 
When it finally popped and broke loose I though the stud had snapped off level with the head. I could not believe that that small of a bolt could be so tightly frozen.

^^^^

They corrode, literally form a chemical 'weld' (threads). So unless the bolt is strong enough to withstand the twisting force necessary to break the bond, it will snap off (over and over again) regardless the method used to turn it. So....coating the bolt threads before installation (anti-seize is your friend) is always a good idea in this application. Also, there are four bolt holes (blind holes) up front on the head. So count yourself lucky if a broken bolt occurs only in one the thru-holes, at least you can drill all the way through them.
 
I wonder if it's something about being back there right against the firewall and above the exhaust that it gets hotter than the other bolts and therefore seizes up somehow.

Possible. But it could occur on any bolt whose threads have been exposed to moisture (direct or atmospheric). Galvanic Corrosion occurs when two dissimilar metals are in contact with one another and exposed to an electrolyte or conductive solution. Aluminum forms an Oxide which is an extremely hard substance.
 
^^^^

They corrode, literally form a chemical 'weld' (threads). So unless the bolt is strong enough to withstand the twisting force necessary to break the bond, it will snap off (over and over again) regardless the method used to turn it. So....coating the bolt threads before installation (anti-seize is your friend) is always a good idea in this application. Also, there are four bolt holes (blind holes) up front on the head. So count yourself lucky if a broken bolt occurs only in one the thru-holes, at least you can drill all the way through them.
Everything is definitely going back together with anti-seize this time. And I'm going to buy some new bolts. I don't trust these factory ones.
 
This is the year 2020 in one picture.:arghh:

Thanks for all the tips everyone. I went and tried some suggested approaches, and ended up just breaking the stud off, more or less flush with the head. So at that point I tried drilling a hole through it to use an easy-out, but since I couldn't get a straight shot at it withe the drill bit due to the firewall the hole wasn't as straight as I would have liked. Anyway, I put the easy out in there and then it broke off. SO I've gone from bad to worse. Pretty sure I won't be able to drill another hole through the stuck easy-out since it is hardened. I swear someone at some point must have epoxied this thing in. There is no way a little M6 should be this hard, especially since the other bolts for the valve cove came out with ease. I'm at a loss as to what to do at this point. Maybe I should just pull the whole head and have a machine shop fix it. I'm at 120K miles, so maybe a preemptive head gasket replacement wouldn't be a bad idea while I'm at this anyway. All this over a f'n valve cover bolt...

Here's a photo of it now with the broken easy out jammed in it for what it's worth...

View attachment 2339146
 

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