1972 250 Exhaust Manifold Removal

[lowellchu9]

I am in the process of replacing the intake/exhaust manifold gasket on my 1972 250 with the SOHC, inline 6 engine.

I have removed everything, but I am unable to separate the 2 down pipes from the manifolds. I have even removed the bracket at the rear of the transmission, but to no avail. Please help!

[Petteri K]

The rust has done its job! They are there so tight that usually they bend or crack when removing with force.

Mine were so tightly that I had to cut the pipes with angle grinder and then I was able to get the manifolds out from the engine. The stud what was left I had to cut out with grinder too.

[JimFreeh]

If you've removed the 3 fasteners from each downpipe, as well as the trans support, try spraying some penetrant at the joint.

Once the collar is loose it's only rust holding it on....

Might also remove the rubber donuts further downstream to get a bit more leverage on the system.

Jim

[lowellchu9]

Thank you, everyone, for the helpful advice. I'll spray some PB on them and see if they'd move. Otherwise, out with the angle grinder!

[cth350]

Before you use the angle grinder and before you bang on the cast iron manifolds with a hammer (which can crack the cast iron). Try banging on the pipe with a hammer.

Getting pentrant in the seam is doable, but not very effective. Once it's in there, few hammer blows on the pipe might do it.

I've jacked up the car, disconnected all the support hangers on the exhaust and grabbed the tail pipe. Wiggling it from one back tire to the other will get the system's attention.

-CTH

[lowellchu9]

Thanks for the advice. I'll loosen up the pipes at the rear before cutting them.