Okay guys, another issue. My driver side exhaust manifold has a hairline crack. Is there a way to fix it or am I lookin at getting one that isn't?

 

I have heard of guys welding the crack with unknown wire but it won't last long. The heat on them and their expansion and contraction of the cast iron is different than the weld.

 

Where is the crack in the mani? You could probably braze it.

 

It's basically right down the middle.

 

factory logs ? good excuse to get headers if you ask me .

 

While it maybe more work than it's worth, there is a product that the marine industry uses to seal the risers (that's the exhaust manifold on a marine engine) on inboard engines. It's not exactly like JB weld, but it is like that type of product. And it does work on cast iron very well. I can my buddy that has a boat shop and get the name if you want. But I would either go for headers or find one at the junk yard.

 

Cast can be welded just fine IF you, or someone you know, has the experience. Most people just don't have the experience/knowledge to weld or braze it. Google 'welding cast iron' and it'll give you an idea on procedures and perhaps some insight on deciding to weld or purchase. FWIW, just because someone can weld doesn't mean they can weld cast.

Dan

 

I knew a welder who'd heat up the whole manifold up in a high temp oven all day before attempt welding it.

This stuff works pretty good on a burned out matting face where the exhaust has eaten a path cavity. ThermoSteel High-Temp Metal Repair
I repaired a buddy's exh manifold a number of yrs ago. it lasted until he parked it a couple yrs. a later when gas got to high and drove his Datsun pickup ago 10 yrs ago now.
Orich

 

The crack goes across the top but the back is solid.

 

In the mean time....

I'm going to see if I can find a good used one. I don't want to go to headers because I want to keep the exhaust intact as is. A lot of money I don't have to solve the problem. Would love to though.

 

Make sure you get a truck & not a car one as the lower exh exit turns out at a different angle. Most have a big Tee casted on them.
Orich

 

1965/74: There are two different FE left (drivers) side exhaust manifolds for F100/350's. One was only used with a heat riser valve.

C5TZ-9431-A .. Left Exhaust Manifold-Use with heat riser valve / Obsolete

1965/67 F100/350 352 / 1973/74 F100 360/390.
-------------------------------------------------------
C8TZ-9431-B .. Left Exhaust Manifold-Use without heat riser valve / Obsolete

1968/72 F100/350 360/390 / 1973/74 F250/350 360/390.

 

Thanks GK. Can you get the name? I appreciate it. Todd.

 

Most likely Blue Magic 8024 ThermoSteel High-Temp Metal Repair
My son tried these on his tocoma and 3 days later it just vibrated loose. I'd say your wasting your money & time with that big of crack.

Orich

 

72CC428 I sent you a private msg (PM).