Can you remove the head with the exhaust manifold attached to it? That's how I do it on an E53 and E39.. I do it with an engine hoist..definitely the easiest way, If I needed to remove the pass-side engine mount (didn't have to on E53 and E39), I would support from oil pan using a jack and a piece of wood.

 

yeah it's certainly possible to remove the head with the exhaust manifold attached, but there's not a lot of space to work with on the E46 XI. i don't have the engine hoist or floor jack which is why i'm thinking of trying a stack of the solid 4 inch concrete blocks from home depot. with wood on top so as not to damage the oil pan. that way i can lower the quickjack until the engine weight is taken off of the mounts. that should let me remove the passenger side mount and get access to the exhaust manifold bolts.

 

What you describe will work, but everybody i know who has removed the exhaust manifold the way you have described it has regretted it. If you are not taking the head off (you are), then you have no choice if you need to remove exhaust manifolds. But if you are taking head off, just leave them attached and pull together. If you don't want to rent/borrow an engine hoist., perhaps you can use a come-along attached to the ceiling of your garage???...you will either have to remove hood or put it in the near-vertical service position. Also, while it is heavy, but its also possible (in theory) to have a buddy help you remove the head with the exhaust manifold by hand...Like the E53, you will need to lift it an inch and then pull it toward front of car.

 

i tried freeze off and sawzall to remove the exhaust nuts but no luck. too badly rusted. but with a mini ratchet i was able to remove all 16 nuts and the two exhaust manifolds from the top.

 

Those studs for exhaust down-pipe are pressed into flange. with manfolds off you can try tapping them out, but many people just drill them out and replace with proper exhaust bolts.

 

thanks yes i think that's a good idea to drill them out. i tried cutting the bolts off using sawzall 18TPI medium metal blade but could only cut halfway.

 

Drilling isn't going to be any easier. Those studs are made of a really hard (but rust prone) steel. Heat the flange a lot and beat them out. You will need the header supported properly though so it doesn't just vibrate. Or make a relief cut in the flange so the stud comes out with little force.

 

Yes.. With headers off the car, put one in a vice, cut the stud off flush with the flange. Heat it and soak with penetrating fluid. Then use a heavy punch to pound the stud back out of the flange.

 

mechanic friend recommended these extractor sockets- has anyone tried these on the exhaust nuts? they were M10 before rusted?

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What I usually do is heat them up with mapp gas, hammer on the smallest impact socket, SAE or metric, that will fit and have at it.

I also have a set of Metrinch sockets which are great for rounded nuts. Due to their design (similar to snap-on and amazon above) they grab the bolt or nut on the sides, not the corner.

 

no luck with the propane torch. sawzall with the diablo carbide blade did the trick.