Jump to content

well seemed my header cracked in half!!!!


saints
 Share

Recommended Posts

put the 58 buick in the garage and set for a few days. went to start it up and it was loud like an exhaust leak. Thought it might be a gasket leak. found a nice large crack all the way around it. when it heats up it closes off so it isnt as loud but my question is Can i get it welded up? or am i stuck paying a crazy amount for a ebay one?

IMG_1343.JPG

Link to comment
Share on other sites

The answer to your question is YES it could be welded. Not just any welder but one that has welded cast iron before. Cast iron must be pre heated and welded slowly to avoid further cracking. Not cheap! Best place to look is in a rural farming community that has an old black smith shop. Those guys have been welding cast farm implements for years. I don't know what "crazy"amount is but I might have one. Is it a single or dual exhaust and what series '58. Appears to be the drivers side.

Link to comment
Share on other sites

Not worth trying to weld if for single.  They are still plentiful at the moment.

 

Several years back I found an NOS one for a single.  Mine was badly cracked in 3 places and I couldn't find a good one for a dual, so I bought it and had old time muffler guy modify my exhaust pipe coming off to fit.  It is still on my Roadmaster 75 to this day.  When the one on my 76C was cracked, I had it welded as it wasn't as bad.

 

It makes no sense that they made 2 different styles.  Both bolt up the same and there is no difference in clearance or outlet diameter.  Must have had engineers working in silos.

Link to comment
Share on other sites

1 hour ago, 60FlatTop said:

I wouldn't put those lock washers back on after it is repaired, either.

 

And use GM manifold bolts, not new ones from a hardware store.

 

Cast iron SHRINKS!  Many Chevy exhaust manifolds used flange head bolts with a "heat washer" under each bolt, then the "French lock" to keep things tight.  That arrangement lets the manifold move under the bolts as it heats and expands AND shrinks with use.  If you removed the manifold, the end holes would not line up with the bolt holes, until you stretched them out with a particular tool (there is one for small block Chevys, which can also be made with two bolts and a nut).  Knowing that, the only real way to do the welding would be in a jig duplicating the attachment at the cylinder head, to me.

 

IF the lock washers were used, it made the manifold "clamped" to the bolt head, not allowing for the hot/cold expansion/contraction to happen.  Hence, cracks, eventually.

 

NTX5467

Link to comment
Share on other sites

13 hours ago, NTX5467 said:

 

Cast iron SHRINKS!  Many Chevy exhaust manifolds used flange head bolts with a "heat washer" under each bolt, then the "French lock" to keep things tight.  That arrangement lets the manifold move under the bolts as it heats and expands AND shrinks with use.  If you removed the manifold, the end holes would not line up with the bolt holes, until you stretched them out with a particular tool (there is one for small block Chevys, which can also be made with two bolts and a nut).  Knowing that, the only real way to do the welding would be in a jig duplicating the attachment at the cylinder head, to me.

 

IF the lock washers were used, it made the manifold "clamped" to the bolt head, not allowing for the hot/cold expansion/contraction to happen.  Hence, cracks, eventually.

 

NTX5467

 

Yup - ran into this years ago when replacing the crossover pipe on my '89 C1500.  I decided to remove the passenger side manifold so I could replace the exhaust pipe studs, rather than wrestling with them on my back in the driveway.  When it came time to re-install, with the center manifold bolts in place I discovered that I couldn't even start the end bolts into the head, as the manifold holes were about half a hole too short!  I wound-up starting the engine and letting it idle for a couple of minutes, and *voila* the bolts could all be re-installed!  Needless to say, I never removed that manifold again!

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share

×
×
  • Create New...