I recently did a rear main seal/oil pan gasket/transmission filter job. It took me four weekends. The main thing slowing me down, besides being a complete amateur, was rusty and tough bolts. I was thinking about getting an impact wrench. Then I found out the were pneumatic. I looked into cheap air compressors and just gave up. I think spending a few hundred dollars on a new air compressor and impact wrench is a little over the top. Then I saw a commercial for this wrench from Sears(200 ft lbs, 3000rpm, 19.V cordless) for around $100. I see a possible head gasket job in my future. Is 200 ft lbs strong enough to deal with rusty exhaust bolts or others I might reasonably deal with on a 2001 Jeep, or is this one only good for speeding up the job of unscrewing all the bolts? So help me decide if its worth it to get an impact wrench for home use.
How about renting an air compressor, and maybe also the impact driver?
I know compressors are a staple at equipment rental shops, just not sure about wrenches, but you may find buying one of those is affordable, and eventually you’ll break down and get a compressor of your own.
As for the electric option - maybe you might be able to persuade your local Sears into letting you borrow one for a couple of minutes to see if it will crack loose a couple exhaust bolts. The reviews I skimmed through make it sound good for changing wheels, but those aren’t usually solidified into one monolithic glob of rust like exhaust bolts tend to be.
Most torque specs for impacts seem to be optimistic IMHO.
200 ft lbs will snap off an exhaust stud. (assuming that the wrench really does produce 200 ft lbs.)
The second problem is that your standard impact won’t fit on the exhaust manifolds of many/most V engines.
I have both electric and pneumatic impacts. For a cylinder head I would probably opt for an air ratchet before an impact.