Broken Exhaust manifold

[69crewcab]

Group
went to look at another IDI motor, and it has a blown out exhaust manifold, that went and coooked the fuel pump on the block..
anyone ever hear of this??
What causes the manifold to blowout? Castiron usually handles the heat well

 

[icanfixall]

This has been talked about only a few times here. I really don't know why a manifold breaks. Some feel its excess heat but I don't think thats the cause. This isn't a common problem thats for sure. Burning up the mechanical pump sounds like the driver didn't hear or care what was happening to the motor.

 

[towcat]

overfueling and running flat-out while overfueling will do this.
I've seen trucks running the manifolds and turbo with a bright orange glow and the manifold are done after a few sessions.
if you can run a compression on the motor and it reads good, buy it, replace the manifold and turn the fuel down a little.

 

[91f2504x4]

I haven't seen many of the diesel fords have manifold problems but it is very common on the small block gas ford trucks. When I bought my truck and it had the 351w in it, it developed a crack in the center of the manifold shortly after buying it. I took it off to replace it one day and it just fell in two. I was telling a friend of mine about it, who has a 97 F250 with a 351w and he wanted me to show him where it cracked, so I went out to his truck and I pointed at the spot and then noticed his was cracked too. After this I began to look at the manifolds on trucks that were sitting around and at least half of them have a broken manifold on the passenger side right in between the two middle cylinders. I know this isn't cause by just "hotrodding", the friend of mine that has the 97 is fairly old and he putts the poor truck around all them time, it is probably full of carbon, and he bought it new in 97.

On my truck when it had the crack you would only faintly hear it when idling and cold, once the truck got up to temp the crack would close and you wouldn't even know it was there.

 

[Dsl_Dog_Treat]

I haven't seen many of the diesel fords have manifold problems but it is very common on the small block gas ford trucks. When I bought my truck and it had the 351w in it, it developed a crack in the center of the manifold shortly after buying it. I took it off to replace it one day and it just fell in two. I was telling a friend of mine about it, who has a 97 F250 with a 351w and he wanted me to show him where it cracked, so I went out to his truck and I pointed at the spot and then noticed his was cracked too. After this I began to look at the manifolds on trucks that were sitting around and at least half of them have a broken manifold on the passenger side right in between the two middle cylinders. I know this isn't cause by just "hotrodding", the friend of mine that has the 97 is fairly old and he putts the poor truck around all them time, it is probably full of carbon, and he bought it new in 97.

On my truck when it had the crack you would only faintly hear it when idling and cold, once the truck got up to temp the crack would close and you wouldn't even know it was there.

The pcv system plumbing design into the intake manifold is the root cause of those Dusty.

Darrins 302 on Droopy was the same way. He had me reroute the pcv return up into the middle of the intake plenum instead of the rear of it to more evenly distrubute the oil vapors being reingested back into the engine.
Kinda like our CDR problem with the IDI's on #7 & 8 cylinders.