1.6 ABU valve to piston clearance??

[mike-a]

Does anyone know what the valve to piston clearance is on a 1.6 ABU engine? Have head gasket problems and need to skim the head but need to know how much I can machine off.
Thanks

[tech1889]

machine to minimal clean up..

[Wayne]

As above a light skim should be all you need.

[danny_p]

just give the head to machene shop,  they will know what needs doing

you don't ask them to take X off you give them your phone number and leave it with them

  they often give it a very light skim to start with and if its warped it shows up as untouched metal so they then measure the differance and skim it that much.

you'll get a phone call saying it's cluked or done simples

if it is really bent and clearances become and issue there are 3 options

1) get a new head
2) recesses the valves a bit
3) add another headgasket     ( if heads are £££ and youve had to take shedloads off )

[mike-a]

I'll be skimming it myself on a mill at work.Usually only takes .25-.5mm to clean a head up.
The thing I was worried about is that in the Haynes manual it says the valve seats will need recutting if the head is skimmed to avoid piston and valve contact.Surely the clearance must be more than 1mm? It's not a performance engine afterall! I've machined plenty of Rover and BMW heads but never a vag head.

[tech1889]

I wouldnt use a mill for is they normally grind them as milling doesn't leave a uniformed finish.. We used to use a surface grinder much better finish and quicker in some cases..

If the head is in good condition you will only need to take a few thou off it i wouldn't just go a take .5 or a mm off if its not necessary..

[mike-a]

Thanks all.
Have machined fair few heads in my time so won't be charging in and taking .5 off straight away.It's an aluminium head so I can't grind it as we don't have a wheel for aluminium so I'll be using a 8" fly cutter on a Bridgeport CNC mill.
Was just querying the Haynes note about machining the valve seats and wondering just what the piston/valve clearance could be.
All should be ok for a light skim I think.

[tech1889]

sounds like a good mix 8" fly will be fine.. you use bridgeports ?? we used to use mazaks and loved them so easy to get on with..

[mike-a]

We've a couple of big Mazaks,four Bridgeports with Heidenhain and three Hurcos with Win Max(POS!!) and we use Solidedge for CAM work.
Just need to have a quiet day when I can get on the machine at lunch for a bit of head work!