ZRX Head Gasket - External Tags & Hole Shapes vs. Block

[pertonpc]

Hello All,

I have just got a factory head gasket and it looks a bit different to what was fitted.
Part code is 11004-1377
Plus some of the holes in both old & new are smaller in the gasket than they are in the block and head.

Here they are -





The head gasket on the Kawasaki parts diagram does have the extra outer tags - including the silver rectangular one with markings by the cam chain tunnel.

These extra bits stick outside the engine and don't do anything from what I can see. Is that because this gasket fits more than one model?

They seem a bit too well formed to be non-functional.

So does that mean I had an after market head gasket fitted or what?

Also how come there are small circular holes in the gasket which line up with the two longer holes at rear of each cylinder - surely this restricts the flow of whatever goes up there?

Engine builders to the rescue please

[z1bman]

the small holes in the gasket are to allow coolant to flow through the cylinder head

[pertonpc]

Yes I get that Paul,

. . . but just found it strange that the elongated hole is way bigger than the small circular hole in the gasket.
It is elongated the same shape on block and head so I was puzzled why the gasket would act as a restrictor to the flow.

General rule I thought was increased flow = better cooling.

Any thoughts on why it has those silver circle tag things on it - cos they just stick out when it is fitted.

Did new ones have the stick out bits of head gasket showing when you worked on them??

[sid123]

the bit sticking out with the number on it may be a part code for factory assembly - whereby head gasket is selectable depending on piston height and head cc volume ( they do it on diesels ) that way engine is built within spec for type approval / emmissions etc. they tend not to bother on petrol engines for replacement ones,

The head gasket is a multi layer type and the round holes outside the head have small metal rivets to keep the layers together

[pertonpc]

Cheers Sid,

A couple of other guys came up with that explanation for the external tags as well.
Apparently the factory build gasket had a cross punched into the tag and these new ones have the silver rivet style fastening - to keep the three layers lined up.

From Mark

[chrisu]

just got a wiseco 1075 kit for my Z1R with the same gasket construction

[doebag]

General rule I thought was increased flow = better cooling.

Yes, providing the coolant is flowing where you want it to flow.
Many engines will run hot if the thermostat is removed, as the flow does not reach the radiator but takes the path of least resistance, which may well be back around the block.