Photo shows two head gaskets .The lower one for a 3.4 (used)and the new one for a 4.2.can someone comment on the small holes in the 4.2 to allow the water flow from head to bloc
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I believe its designed to restrict the flow of water through the head so that the water can collect more heat from the head?
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And 4.2 version has 2 more holes (nonexistent in 3.4) at the engine rear (rightmost on pic, cyl. 1). Where do these go ? Extra studs ?
Seems strange seal manufacturer to be improving engine design unless it is a copy of Jag original pattern ?
The holes in the 4.2 gasket are sized to force more water to the exhaust side of the head. I believe you will find one side stamped “TOP”
The later 4.2s have 2 additional water ways at the rear of the block/head,
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Intresting Mike.In the past with 3.8 heads if i had that amount of passage in the water passages in the head id be having a panick attack.Im not fitting that gasket right now ,its for Ron.but wanted to check it was correct THANKS
John,
Early 4.2 Heads/blocks and thus HEAD GASKETS from 1964 to c1968/9 Had the same holes/water passages as 3.8 and 4.2 Head Gaskets…
Its only post 1968/9 4.2 HEAD GASKETSA that have the rear-end extension and additional water passages as a result of both the later blocks/heads having extra/extended water passages at rear end.
Clearly to be sure, you should get the head gasket that properly aligns with the head and block being used, albeit more than one punter has tried to fit a later head on an earlier block and wondered why coolant pours out…, with many butcherous efforts to weld/up block the non aligned extra holes…
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the gasket is for a 4.2 engine not the xk140
Thats my point John,
The Gasket is for a late (post 1969) 4.2 - all earlier 4.2 (1964-1968) have the same shorter gasket (no extra water holes) as a 3.4 or 3.8 . Thus usually gasket suppliers quote Engine Numbers of Models and Years…