The V8 Owners Forum -

why is it that at the top of a rover V8 3.9 block, there is 1 large water way at the rear, and only a small hole at the front (about 8mm).... but on the heads the holes that fits over the 8mm hole is a hell of alot bigger and the same size as the rear one?????


oh and plus where the inlet manifold joins to the heads there are 2 water ways at the front and 2 at the rear but there are only 2 waterways in the inlet manifold, none at the rear, but you can see where the water touches the rear of the inlet manifold as there are 2 rust square marks left on it....

can any1 shed some light on this

They are designed like that so that the cylinder heads are not handed. Reduces costs when they are cast, instead of using two different castings.

The heads are interchangeable

As above, plus:

The water is pumped from the water pump back through the block. Then it rises up through the large holes at the back into the heads, whereupon it comes forwards. At the front it exits up into the inlet manifold behind the thermostat housing.

The small holes in the block at the front are to ensure it bleeds.

Chris.