Aluminum heads , 12 mm socket or wrench required . Anyone care to venture a guess whether these bolts will thread out or twist off ?
Oh boy. Best of luck on that one. Use plenty of thread penetrating oil. And time and patience.
Edit: There’s a complete thread here from several years ago about ways of dealing with stuck fasteners. A lot of good ideas in that thread if you can locate it. A lot of the experts say to first press on the bolt in the tightening direction a little, before trying to untighten it.
Yeah…good luck. If you use a wrench or a socket…make sure they are of the 6-sided variety. That helps to insure that the bolt will not round off when you remove it. I’m not a big fan of 12 point sockets or wrenches for that very reason.
80% likely the bolts will break. Of those that break, 20% will snap off at the head leaving NOthing to grip, requiring an Easy-Out. 75% chance that drilling the bolt for the Easy-Out will break the drill. 100% chance that really filthy swear words will be uttered in disgust - keep the children AWAY!
99.9% chance that these percentages are comPLTEly made up!
I loosened one bolt & exerted as much pressure on the 2nd one as felt safe & it didn’t budge . I’m pulling the engine & having a tough time getting the y pipe unbolted from the manifolds . Didn’t want to do it but will probably cut the y pipe & leave the manifolds on the engine . I’ll deal with unbolting the pipe stubs from the manifolds after I get the engine out . Last thing I want to do is deal with bolts twisted off in the heads .
Since the engine is coming out anyway, I think your plan makes a whole lot of sense.