[anders]

Originally Posted by FJ40Jim

Don't do this. Srsly.

The coolant flow through the engine starts with the WP shoving cold coolant in the front of the block. Coolant moves to the rear of the block, circulating around all cylinders. At the rear of the block, coolant moves upward through large openings in the HG. It then flows forward through the cylinder head. exiting out the front side of the head to go to radiator.

If the t-stat is left out, then some of the coolant will flow through the bypass circuit, instead of the radiator.

If the HG is opened up everywhere, then the coolant will take the path of least resistance, coming in the block at the WP and going straight up to exit out the side of the head. Coolant will not be forced to circulate to the rear of the head or block. The coolant gage will not get hot because the coolant is not pulling waste heat out the back cylinders. BTW, the tiny holes in a HG are called steam holes, because they are supposed to allow air bubbles out of the block to prevent small air pockets from turning into large steam pockets. They are not for coolant circulation.

HTH

Very true.. But there is only steam holes on the injection pump side, the manifold side of the head gasket is for coolant flow, notice the picture of the head gasket, the coolant passages on the manifold side get larger from cylinders 1 to 6.