Heart Transplant at 278,000 miles

I thought of that myself. 100 ft lbs is a lot of torque, and those bolts are under a lot to stress. The heads are begging to pop off at that torque.

 

When you said "stripped", it 1st sounded like the threads were gone, but now it sounds like you really meant rounded. Okay. Other ideas from a 3 decades Aerospace Machinist. After the rounded bolt has been thoroughly soaked with a penetrant/fluid if there's room, use a little angle grinder to make your hex a little smaller, then use the next size or 2 down socket with breaker bar. Or, what's sure-fire, is to heliarc a big as practical peace of Steel onto the top of the rounded hex - then you have a decent way to grab ahold - with an open- end wrench or whatever. Plus, a lot of time, the weld Heat will significantly help with loosening a frozen Bolt.
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It’s a rounded Allen key. What would the procedure be for that?

 

Same thing. Heliarc a Allen wrench into the round out out hole & you'll be good to go. That way you'll actually be able to put 2 wrenches box, ratchet, whatever on it (one on top of the other) - turning & pulling like they're a T-handle.
Here, just took a picture


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I like it, but I think the OP is looking for something a little less high tech. Like stone knife and bearskin simple.

 

I know hindsight is 20/20, but moral of the story is get the right tool?

 

SN please explain the rope in the cylinder trick I have never seen that before.
Thanks.

 

I like hills suggestion. Couple that with my impact gun gimmick and it will come out.
It may take 30 mins of bumping the impact gun but eventually it will come loose.
Patience.

 

Iirc, he's already drilled them out instead.
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When I was changing the clutch on my wife’s 4 Runner I broke off 2 exhaust studs on the drivers side exhaust manifold. I tried a stud extractor first and broke them both. Then i removed the manifold and tried welding bolts to the studs. No joy. Wound up having to drill them out. Sometimes the hard way is the only way. At least I had the option of removing that exhaust manifold.

 

Another tack: Eric the Car Guy uses torching here:

 

Great photos, very interesting to see how much carbon accumulated at 278K miles.

Did you have a chance to look at the camshafts to see what wear was present on the bearing surfaces and the cam lobes?

 

How does the bore in that cylinder look?