replacing exhaust

[fivespt]

Im replacing the exhaust on my 01 sport at 60.000.Has the 4.0 V-6 HO. everythig is rusted bad on the exhaust. should the cat be replaced to , any prob. with these. its got 2 small cats with a ox sensor between them. also have the error code running lean both cyln. vacum hose seem to be ok. would a very leaky exhaust trigger this?

 

[jremington59]

Yes it will. If there is a lot of exhaust being lost before the 0 2 sensors.

Chances are if everything else is rusted the cats are to. You're probably also going to have an awful time getting the bolts out of the exhaust manifolds. You better spray them with blaster every night for a week before trying to get them out.

 

[griffin55]

My bolts were rusted on so badly that I had the cut the flange bolts. They're spring loaded, so that was fun.

Then I had to drill out one of the holes on the manifold. It took me 3 hours to get everything out and 20 minutes to install the new exhaust.

Winter in Wisconsin....

 

[bluestream1]

If your exhaust studs are too rusty, I have found that broken exhaust studs can be easily removed by heating the exahust manifold red hot. Then take a large sloted screwdriver and tap in into the broken stud. The stud can then be removed by turning the screwdriver and backing out the stud. Has worked many times for me.

Also, sometimes it is easier to take a sawzall and cut the exhaust pipe below the manifold. Then when you put the engine back in, line up the pipes and weld them together.