What Is the clearence for the inlet, exaust valves. I have looked through my car manual, even googled, NOTHING!! lol. tappets are sounding rattly so im going to adjust them. would like the hot adjustment in metric and Imperial (thau) please. (I.E For a 4K Starlet .25mil For Inlet .35mil For Exaust)
Another Kiwi on the forum :wave:
I reckon 0.40mm inlet, 0.45mm exhaust, +/- 0.05mm. That's 15.7 'thou' (0.0157") and 17.7 'thou' (0.0177") respectively, tolerance 2 'thou'. Do yourself a favour and use a metric micrometer and feeler blades
The shims are about the size of an old 20c coin but quite a bit thicker.
To change a single shim, you need a special tool (FIAT A60421). The tool holds the bucket down so that you can pry the shim out. It is a tight, oil-held fit. I find a strong magnetic pickup tool helps, too.
Without the tool, the best approach is to measure all clearances and write them down, then take the cambox off, being careful to push each bucket down onto the valves (don't let them fall out everywhere). Then measure the thickness of each shim and write that down too. Work out how much thicker each shim needs to be. Some of the shims will probably exchange with others to get the correct thickness.
You'll probably be left needing three or four shims, which you can get posted down from Maurice Thomson Motors in Te Awamutu (07 871 7311), or you can track down a more local FIAT specialist.
Then you can put all the shims in at once, with some Loctite Master Gasket 518 between the cambox and the head. This translucent red anaerobic sealant (NOT silicone) does an amazing job between close-fitting surfaces - glues them together - and makes the thin paper gasket unnecessary. You will need a new gasket for the tin cover (cam cover), though.
Some dodgy engine shops just grind the end of the valve stem down a bit, but that is very hit-and-miss and obviously no use if the clearance is too great.
Best of luck! As Chas says, once it's done, it won't need doing for tens of thousands of kilometres.
Also, I don't want to disagree with Davren's findings, but I personally found that 0.50mm for the exhaust clearance was too noisy (taking into account a +/-0.05mm tolerance which is about what you can achieve through 'average' adjustment process, since you have to measure not just the clearance but also the shim to correct it - the errors do add up, so take care...)
0.45mm is still a huge clearance by older-engine standards - race engines tend to run 0.20mm or less.
Cheers,
-Alex
