Hello, I took this head off a Punto, there's some pitting on the mating face, mainly on the waterway you can see in the pic. Does this need welding up and re-surfaced?

If it were myself i'd just get it skimmed. Shouldn't cost too much.

I'm worried about the pitting around the fire ring of #1.

See if you can find another head --

Ah well, there's another head on my car, which is hopefully in better nick, this one came with an 866 cam though, that's the Punto 70 cam is it not?

P75 cam. No reason, though, with 2 sets of shims at your disposal, not to pop the P75 cam into the other head. If it's coming off, lightest possible skim, get them to recut the valves, too. If you need the odd shim, eurocarcare in Derby do them for something like £3 a hit.

I'm a bit foggy on shimming, I know what needs to be measured and set properly, but do I swap the whole bucket over? Or does the top hat come off, if so how does it come off?

On the FIATs the shim is on the top of the bucket and bears directly on the cam. So much easier than shim under bucket systems.

The Haynes Cinq manual covers it pretty well.

Good stuff, found a guide on here, looks like I need a micrometer, cheap projects really are never cheap.

Machine Mart do them for about £6! But the shims are generally etched with the size, so you may be able to get away without one. A digital vernier is fine for this job if you have one knocking about.

I know it's not expensive, but things are starting to add up, if you know what I mean.

Not changing coolant is a recipe for pitting a head, lotsa heads will be pitted as most little fiats are run on low maintenance, neglect...

It might skim off before reaching a interference level, but you may need to shim even if the head surface is good to get it back to flat. If you have got an unwarped and skimmed head to hand I'd use that...

Noel

before you spend some money take the head to somewhere that skims heads and ask their advice, chances are a skim will take most of that out

there is quite a few mm to go before it starts to affect where the fire ring sits

I had similar but worse problem a few years ago but the head was able to be welded then skimmed and it didnt cost a lot, I went to 2 or 3 different places to get quotes as they were in the same area

Pep0 said:

Not changing coolant is a recipe for pitting a head, lotsa heads will be pitted as most little fiats are run on low maintenance, neglect...

It might skim off before reaching a interference level, but you may need to shim even if the head surface is good to get it back to flat. If you have got an unwarped and skimmed head to hand I'd use that...

Noel

Click to expand...

Hang on. In what sense does shimming the valves (after re-cutting) have anything to to with skimming the cylinder head?

levemircento said:

before you spend some money take the head to somewhere that skims heads and ask their advice, chances are a skim will take most of that out

Click to expand...

But he has 2 heads already, now..............

fingers99 said:

Hang on. In what sense does shimming the valves (after re-cutting) have anything to to with skimming the cylinder head?

Click to expand...

Hi

Well spotted typo graphic error sorry - most people will detect the correct meaning from context, dont think I can change it now?

Noel

Probably timed out. Not to worry!

fingers99 said:

But he has 2 heads already, now..............

Click to expand...

That makes me sound like some kind of freak, true enough though.