Cracked Manifold

[Daybreaker]

Ive had this lovely Daybreak 7.4 v8 for 10 years now. The r/h (passengers side manifold ) has now cracked again. I'm about to order the 3rd one, the last one which lasted 18 months. Rock auto advise replacing the motor mounts.
However some people say that some springs are involved with the manifold to give flexibility which avoids strain on the manifold from the weight of the exhaust. And some people say never heard of it in 30 years of being an RV tech.
Im from over the pond so I thought id ask the widest rv community in the world.
Can anyone help please?
Cheers

Bill Kincaid

[Sappy2]

Yes - GM did use a bolt and spring to fasten the exhaust flange to manifold, this allowed some movement without losing the seal on the donut gasket. But I must be honest, the only time I ran into broken manifolds was when the chassis was running too lean, and the heat was stressing the manifold (lean mixture = hotter temps). Additionally, there may be something with vacuum and centrifugal advance issues (again, incorrect timing results in exhaust temp changes). Just saying, you may have something else happening that is root cause.

[16ACE27]

Spring attached exhaust to manifolds have been around for decades.

[ducksface]

I don't know where the exhaust manifold cracks.
Ask your mechanic about exhaust wrap and if it's a temp differential crack or a vibration crack, or torsion crack.

[16ACE27]

Originally Posted by ducksface

I don't know where the exhaust manifold cracks.
Ask your mechanic about exhaust wrap and if it's a temp differential crack or a vibration crack, or torsion crack.

Would that be the same mechanic that never heard of spring tensioned exhaust joints?