This is just a general question of curiosity, not model-specific. When you have the head gasket replaced, why do you only skim the head, and not the block? My theory is that cast iron (block) is more resistant to damage and warping than aluminium alloy (head). Does that mean the block and head need skimming in an all-alloy engine then?

You answered your own question . And yes its more likely in an all "alloy" engine that the head and block would warp from excessive overheating and both need skimming.

I know of a VW Polo that needed the block skimmed as well as the head and that was a Cast iron block too!.

ChrisUK said:

I know of a VW Polo that needed the block skimmed as well as the head and that was a Cast iron block too!.

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Was that a 'small but tough' Polo? The same 'small but tough' that my mate rear ended in a Focus? Repairs to the Focus: a bit of spit and a rub with the finger on the bumper. Repairs to the Polo: £1200. Must have made that block to the same specification as the rest of the car.

the block can need skimming as well. you should check both. my 1242 engine blew a few gaskets because the block wasn't 100% true

arc said:

the block can need skimming as well. you should check both. my 1242 engine blew a few gaskets because the block wasn't 100% true

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how far out was your block when it was checked?

The Rover K-Series engines were reallllly prone to these sorts of issues. And they were legendary for being near enough impossible to repair effectively

Just be glad that you don't have one I think that both block and head needed skimming on them?

Munkul said:

how far out was your block when it was checked?

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i'm not sure. I sold the engine to brooky in pieces, he checked and then skimmed it iirc.

I remember my manager at work blew a head gasket on a Rover K-series, and she sent the car to the scrapyard because they were notorious for head gasket repairs being non-effective.

MikeSalt said:

I remember my manager at work blew a head gasket on a Rover K-series, and she sent the car to the scrapyard because they were notorious for head gasket repairs being non-effective.

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Same happened to me. They did fix it, but it didn't work. So I had a bodge repair done on it and drove straight to the car supermarket where I got a Fiesta lol.

According to a local garage, half of the problem with the k-series was very bad valve seats. So heat spots often caused the head to warp. Skimming the head only solved the problem, not the cause. This garage ground the valves in on every k series head they got in, and they had a very good success rate too.

im sure the failure of the k-series is just because of the extra long thin strech bolts which go all the way through the block, obviously they expand with heat and the bolts just cant keep it all together.

im doing another one right now, what a piece of crap, the head has big grooves worn in on where the gasket sealing ring sits

The performance of the K-Series was quite good though. I had a 1.4 one and it was more powerful than other engines of the same size. They were just engines you needed to service religiously and they'd be fine - the problem with mine was the previous owner didn't.

Still can't believe I had a bloody Rover

they also had a flaw with where the thermostat sat, on the way into the head.. so once it heated up, it opened and flooded the head with cold water :bang:

i think we can agree then that it was an engine that just wasnt designed properly then!

The 1.4 and 1.8 VVCs are impressive engines for their output though.

output and weight, yeah