Valve Clearance Guide

[911f]

I know this is an old post, but for anyone reading it, be sure to note in the pictures where to insert the feeler gauge. Because this thread is correct and I was doing mine today and noticed the Haynes manual shows a definite picture of it done wrong. Specifically the gauge goes under the rocker arm/above the shim. the Manual picture shows it done under the cam/above the rocker arm (though the text in the manual is right). You will NOT get the same measurement doing both. I checked both ways and above the rocker is between 0.04-0.06 mm under the actual clearance.

Thanks for creating this guide - it helped me a lot today.

[brido]

Hi all I'm going to shim my valve clearances and was wondering is a vernier caliper ok to use when measuring the old shims or is a micrometer needed?????

[CMSMJ1]

I use a digital vernier. Also, the shims have the size marked on them - very very faintly

[brido]

Thanks cmsmj1 just wanted to make sure as I only have a vernier caliper(digital) and I didn't know the size was marked on the shims, cheers....

[brido]

Right lads I need some help again with the valve clearances, I have measured all the valve clearances and the shims, what I need to know now is which size shim to go for, I used the formula in the haynes manual so here is an example of what I got,
a = b - c + d
2.29 = 0.13 - 0.15 + 2.27
Now the shim needed is a 2.29, can I get a 2.29 shim or do I have to go nto the nearest one available???

[CMSMJ1]

This is where tolerances come in.

You can have any gap between 0.12 and 0.18 for inlet and 0.21 and 0.27 for exhaust - that right?

So, you showing a 0.13 gap on an inlet?

Leave it... or wait to see what they all are and swap them between each other.

You can get shims from 1.80 to 2.60 as far as I can make out

I have loads of 2.34 for some reason!!


As an aside - I run towards the 0.18 and 0.27 loose range rather than the tighter 0.12 and 0.21 - might be a touch noisier but I don't want that nnnth of a mm to be making my valve and piston become good friends...

[brido]

Here are my valve clearances in your opinion what do you think I should with these clearances?

[CMSMJ1]

I'd probably leave 'em - they are all in tolerance and so unless you wanted to lap the valves in as well then they'll do you til the next time.

If you haeva load of spare shims then you could look to change the tighter ones out..but if it ain't broke..

[brido]

ok thanks cmsmj1 I will take your advice and listen to someone who knows better, when should I check them again?

[katana]

Well finally doing mine over the coming days it the weather holds out.

Wish me luck