Could someone please identify these holden red motor cylinder heads.
I've had them sitting around home and unsure what their off.
Here are the numbers:7429461 K1 27 6
7420081 L5 3
7420109 J35 2

I just Googled and:

7429461 comes up as a 179/186 head which will be an L head.
7420081 also comes up as a 179 head so an L head.
7420109 appears to be a 149 head so more than likely a H head.

You can tell by the L or H cast on the port side.

Thanks for your assistance everyone.

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Originally posted by castellan

quote:

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Originally posted by Dr Terry
7429461 is an HR 186 head. It can be used on a 179 as long as the small water hole on the front face is plugged.

The other 2 are correct.

Dr Terry

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What !
I thought all red blocks were the same as to water holes on the deck and heads.

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I'm not referring to the head gasket face, this is why I said 'front face'.

The difference between EH/HD & later Red motor heads is the water flow around the thermostat housing.

HR to HJ have a water-heated inlet manifold with 2 hoses running from the lower thermostat housing. This housing has 3 mounting bolts & 2 water holes, one large for the main water flow & a smaller one for the lower manifold hose.

EH/HD only have the one (larger) hole hole & a smaller housing with only 2 bolt holes. The 3rd (threaded) bolt hole is present on these early heads, but is not used. The small water hole is not present at all.

If you want to fit an EH/HD head to a later car, you need to drill out this water hole, it's about 10 to 12 mm in diameter. Then everything will fit & work properly.

If you want to fit a later head to an EH or HD this hole needs to be plugged, or you could just fit the later (3-bolt) thermostat housing & plug off the hose outlets with caps.

Dr Terry