Repair, Replace, or just install this exhaust manifold?

I pulled the manifold off to stop an exhaust leak and discovered the small crack's in the photos below. This is my first jeep so I am not sure if this size and the location of the cracks are an issue. Any suggestions would be appreicated.

http://i1216.photobucket.com/albums/dd365/spurphoto/Jeep/DSC_0392.jpg
http://i1216.photobucket.com/albums/dd365/spurphoto/Jeep/DSC_0401.jpg

 

was it leaking there? you could run it if they werent leaking there

 

If it were mine, I would be on craigslist, salvage yards, or some other means to find a good used replacement. If I needed the Jeep I might JB weld it temporarily until I find one. The reason is that is not a single crack but a spider web of cracks and I believe much more difficult to effectively repair...and I would have peace of mind knowing it's gone altogether.

 

I think you'll find the supply of good, used manifolds of this type is not extensive. The 'siamesed' design, with the bolt flange between the intake and exhaust, was dropped in 1981 when AMC updated the 258. The heater flap was replaced by an electric heater in the (now aluminum) intake manifold.

It looks to me like it's already been repaired once - I believe those inserts are an old repair. The inserts also appear to be sitting proud of the gasket surface, which would be a sealing problem in addition to the cracks.

I recall these manifolds are available as aftermarket replacements. You could also upgrade to the 81-on manifolds, but those manifolds must be used as a pair, and will require a carburetor upgrade too, either the matching factory carb (Carter BBD) or a 2V replacement. My '77 258 is running manifolds from an '85 CJ and a Motorcraft 2100 carb, and it was a fairly easy upgrade. Just get everything, including the carburetor linkage.

 

Thanks for the feedback. I do not think it was leaking at this place but it did appear that it would be very near impossible to effect a good, lasting seal with the thing in this condition.