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Was putting the valve cover bolt back in and was torquing the bolts down to 8 lbs ft like everyone said in others posts (yes I know it’s in inch pounds). And I torqued down the bolt closest to the alternator and stripped the threads. Tried using a thread tap to re thread it and broke the tap itself into two pieces. Do I drill the hole out and run new same size threads? Do I just get a new thread tap and re thread the current hole? Heli coil? Not certain what to do. Any help is appreciated.
I used a helicoil on rocker arm threads years ago, worked like a charm. Soak a rag with wd-40 and put it around the area so it will catch and hold any particles, take your time and make sure it's square to the head surface.
I had the same issue Aliminum heads had a stripped valve cover bolt. After reading this thread, I thought no big deal, Just heli coil it.
Everything seemed to be going good.
The I made the mistake of trying to double stack the heli coils. Again no big deal if done proper.
Next, the bottom heli coil was not quite deep enough and the tang broke off.
So, Like a moron I forced the top one till
the heli coil was as flush (it was less than one full turn)
Sadly this caused some binding with the two coils. The valve cover bolt would start but it not go in very much.
so in l my genius I thought I’ll take my 6x1 tap and even things out…
yeah…the tap broke.
NOW I’m really screwed.
the heads are torqued down, new head gaskets ect everything installed.
I’m pretty sure this gonna end up needing drilled and welded up cuz the aluminum heads gonna get damaged removing the tap.
Not sure what’s most cost effective option at this point
PS not tryin to these Jack.
It is a recent enough thread with a similar issue; and therefore, it’s worth adding to instead of starting a new one to screw up the search algorithms.
I had the same issue Aliminum heads had a stripped valve cover bolt.
NOW I’m really screwed.
the heads are torqued down, new head gaskets ect everything installed.
I’m pretty sure this gonna end up needing drilled and welded up cuz the aluminum heads gonna get damaged removing the tap.
Not sure what’s most cost effective option at this point
Yep, been there with the tap. I used this video to help me with my situation.
It was kind of nerve racking having to drill the hole but as long as you keep the drill straight and measure the depth of how much you have to drill you'll be fine.
@66OldsLS So, how did you make out on this? Curious how you got the broken tap out.....
This was a few months ago but I was using a torque wrench to torque the valve cover bolt to 8 ft pounds (apparently what the in lbs spec equals in foot pounds) and stripped it. I tried to use the thread tap on the end of a drill at low speed because I couldn't fit a thread tap wrench in the engine bay, and the thread tap broke clean in half because it got caught in the already existing threads while trying to cut new threads. I got lucky where it broke and was more than enough to pull it out by hand. so I drilled the hole out, cut new threads, installed the helicoil, and everything went fine.
Appreciate it, but that part was easy , I broke the tap off I side the aluminum head being dumb…taps are really hard snd brittle and they won’t just drill out. I’ll figure it out I always do!?
Originally Posted by 66OldsLS
Yep, been there with the tap. I used this video to help me with my situation.
It was kind of nerve racking having to drill the hole but as long as you keep the drill straight and measure the depth of how much you have to drill you'll be fine.
Appreciate it, but that part was easy , I broke the tap off I side the aluminum head being dumb…taps are really hard snd brittle and they won’t just drill out. I’ll figure it out I always do!?
Ohhh gotcha. maybe try using a thin punch with some penetrant oil and try to get the tap to budge, and use something to pull it out. I don't really know how to get a broken tap out. I thought you needed help with the thread stripping out.
They make something called a tap extractor. Not highly successful when a tap breaks in steel. In aluminum, it might work better. They have 2 to 4 little fingers that fit in between the taps threaded flutes. With a good penetrating oil, like Kroil or PB Blaster, you might be successful. Hope this helps....
I found out the hard way to tighten using a torque wrench with the rubber grommet is a no no. I got lucky and only broke the bolt. Now i just tighten it by feel. You can feel when it gets tight. With the torque wrench you wait for the click then it is to late. I used an inch pound torque wrench and broke the bolt.
I had the same issue Aliminum heads had a stripped valve cover bolt. After reading this thread, I thought no big deal, Just heli coil it.
Everything seemed to be going good.
The I made the mistake of trying to double stack the heli coils. Again no big deal if done proper.
Next, the bottom heli coil was not quite deep enough and the tang broke off.
So, Like a moron I forced the top one till
the heli coil was as flush (it was less than one full turn)
Sadly this caused some binding with the two coils. The valve cover bolt would start but it not go in very much.
so in l my genius I thought I’ll take my 6x1 tap and even things out…
yeah…the tap broke.
NOW I’m really screwed.
the heads are torqued down, new head gaskets ect everything installed.
I’m pretty sure this gonna end up needing drilled and welded up cuz the aluminum heads gonna get damaged removing the tap.
Not sure what’s most cost effective option at this point
PS not tryin to these Jack.
It is a recent enough thread with a similar issue; and therefore, it’s worth adding to instead of starting a new one to screw up the search algorithms.
Why did you double stack the helicoils??? Why not just get the right length helicoil in the first place? My statement/question assumes you are saying you threaded one in that wasn't long enough, so you screwed another one in to get more thread engagement?
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Stripped valve cover thread 
