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Hi Guys, I just noticed on my exhaust man. there is 2 cracks, location above the pipe going down. HELPPPPPPPPPPPP...what do I do now, can it be fixed, plugged, is there any around???? I will take all the advice you can dish out. Thanks in advance VT- vt&1/2 is sad.

Hi Vinny,
Take it to a metal fab shop and see if they can braze or weld it. If they cant, I believe I have some sans cracks.
Tim

Both Vintage Power Wagons and and Midwest Military have NOS costing around ~$325, they should also have good take offs for less.

Be aware that the intake and exhaust will probably need to be machined as a unit so they bolt up to the block with no gaps.

Also you can purchase the tapered nuts and brass bushings (4 each), using plain nuts increases your chances of cracks.

Vinny,

When you get your new manifold be sure to torque them correctly, both ft.-lb wise and proper torquing order. They have to be able to m0ve as they heat up and expand and as they shrink when cooling.

If you don't, you will be sad when they crack again.

Hi Vinny,

I had the same problem with my exhaust manifold......seems to be a common problem on these trucks. I called John at Midwest a month or two ago and had him ship me a nice used manifold. He checks the used ones carefully for cracks before he sells them. Took it to work and sandblasted it and it looks like new. I'm waiting to pick up an intake manifold so I can send both manifolds and the entire exhaust system to Jet-Hot for coating without tearing my motor apart. I think (and I'm telling you my memory sucks) the used exhaust manifold was $175...but call John to be sure.

Vintage power wagons sells the exhaust manifold mounting kit with the all new studs and the brass nuts and washers for $60 bucks. A bit pricey for a few studs and some nuts....but could be a life saver if you ruin your originals taking them off.

As for repairing what you've got....it can be done, but you have to find a welder who knows what he'd doing when it comes to cast iron. The manifold will have to be cleaned real well (sandblasted) and then heated prior to welding. If not it will crack when heat from the welder is applied. And obviously he needs to use the right wire. I've seen way more welders do it wrong than right.....and then you're right back where you started. I'd bet it would be cheaper to buy a used manifold, but if you have a good welder friend who owes you a favor it might be time to give him a call. )

regards,
bob

Here is some info I wrote up when I replaced my manifold last week:

http://blog.gieselman.com/post/Dodge-M3 ... ement.aspx

the VPW stud kit is $60 but includes all of the studs, nuts, thick washers and
brass bushings. I paid $26.50 with shipping for just the studs from Rock Auto,
the Dorman part numbers are included in the link above.

This forum post has pictures of what you get from VPW if you buy everything:

http://www.powerwagonadvertiser.com/for ... hp?t=13355

also shows what happens when the intake/exhaust haven't been machined.