griff2494 wrote on 09. Jan 2011 at 20:52:


you're using a vernier, often referred to as a very-near because the reading is open to interpretation. A micrometer looks like ....

and is considered more accurate.
I'd say it was impossible for 7mm to have been machined from your cylinder head. Either the 134mm quoted isn't right or you're reading your vernier wrong!  hence me asking for a picture without the flash 

Min marker? I've never ever looked for a min marker but doubt there is one only because the difference between a new head & a min thickness head is only usually a fag packet thickness, so the marker would be as wide as the maximum you're allowed to skim from it.

tidla wrote on 09. Jan 2011 at 21:06:


None of mine have a window on them and you line a zero mark up on the sliding bit with the graduations of the fixed scale. Either that or the easy way of a digital vernier ......, especially as your arms get shorter! 

Hmm. I wonder what's been going on there?

My guess :

1) The 134mm spec is wrong.

or

2) The head may have been replaced by a refurbed one. They may have also skimmed the top face and then line-bored the camshaft journals so the 7mm has not come off the gasket face. Even still, 7mm seems a lot.

Maybe someone else has a z22xe head they could measure?

Nonetheless, this one is known to run Ok without valves meeting pistons, so it will do so again.

Skimming isn't by any means essential when changing a gasket. OK, this one has clearly been worked on and failed a second time, so it would merit a close look at the head for any imperfections, especially around the fire ring areas, and inspection for any warping. It looks to be good in the photos but they don't tell the whole story.

If the head and block faces appear flat and smooth I would put it together with a new gasket without skimming and see how it goes, TBH.

Kevin

have a read of this. 

http://www.tresnainstrument.com/how_to_read_a_vernier_caliper.html

griff2494 wrote on 09. Jan 2011 at 21:24:


You're reading it wrong. When the jaws are closed the zero on the fixed scale will line up with the zero inside the window. 

cheers andy b

now i feel even more silly!!!!!! after wot you put i reread and guess what ???

yep you guest it 134mm !!!!!! DOH!!!!!!

griff2494 wrote on 09. Jan 2011 at 21:39:


Result! A vernier isn't the easiest of things to read at the best of times hence - a very near - and then when you get older & you know how to read it but can't see to read it without specs.

At least you're sorted now & have learned another skill!