Turbo - Manifolds

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HarryMann: Seems there are a couple of different manifold versions for the JX diesel engine out there. 
Here are some pics (courtesy SyncroAndy) that include those of the heat shields and their fixing, and some comments.

Worth noting is that these manifolds:

Distort and crack, often the flanges for cyls 1 & 4 'pull-back' from the cylinder head face, come loose and start blowing, and a well known crack occurs at the inside corner of the turbo/manifold mating face (see image No. 5 below). These problems are worth knowing about if you have the manifold or turbo off at any time e.g. surface grind/true up the manifold flange faces, inspect the turbo/manifold faces (gasketless, so both must be pretty flat).

The heat shield fixing bosses/lugs/studs are often rusted away and/or the heat shields missing. Whether to replace or not - your choice, they might be a source of rattles but they're there of course to protect the inlet manifold (and hose) from intense radiated heat from the turbo and manifold, all in very close proximity.

JX Mani 01.jpg

JX Mani 02.jpg

JX Mani 03.jpg

JX Mani 04.jpg

Pic below: Crack starting at corner of manifold/turbo flange, quite common, here a small crack-stopper hole is drilled - fingers crossed! Counterbore and hole is for EGT gauge sensor sleeve, if you use one mounted underneath like this, move it about 1/2" closer to the outlet flange, to avoid closeness to turbo compressor housing

JX Mani 05.jpg

Pic below: Custom fabricated stainless heat-shield for JX style manifold - just clears the KKK K14 compressor housing (small cutout)


Also see: Techniques_-_Cleaning/Trueing_mating_faces#Steps_to_get_a_flat.2C_clean_surface