Valve clearances

Technical advice Q&A

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Spark
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#1 Valve clearances

Post by Spark » Wed Jul 19, 2023 8:17 am

Series 1 4.2L 2+2
Advice please on valve clearances
Long time restoration nearly complete and running ok
Having checked valve clearances I have the following measurements
The head has the 4 bolt cams fitted so I am told 0.012 - 0.014 for both inlet and exhaust
Should I adjust from the current setting and try to get all valves to say 0.013 ?
My dilemma is in people experience can you get all clearances the same ?
See attached pics of clearances

Any guidance welcome

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mgcjag
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#2 Re: Valve clearances

Post by mgcjag » Wed Jul 19, 2023 8:28 am

Hi....yes you can get them all the same...but your checking these with a feeler guage in an awkward position......personally whilst your in there I would change the cam bearings if they have been in there from new....and use a torque wrench to tighten them so they are all exactly the same.....then measure your gaps...and set as requires..13 in the middle is ok to aim at....you will probably have the check them all at least 3 times to get them where you want....long and tiresome...Steve
Steve
69 S2 2+2 (sold) ..Realm C type replica, 1960 xk150fhc

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christopher storey
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#3 Re: Valve clearances

Post by christopher storey » Wed Jul 19, 2023 10:19 am

There are only four which are outside the specification , and these only by 1 thou . Frankly, I regard it as impossible to measure accurately to 1 thou, ( particularly if not all the valve gear such as buckets , bucket guides etc have been replaced) , and my advice would be to leave well alone unless on running the engine it is unreasonably noisy at the top end

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mgcjag
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#4 Re: Valve clearances

Post by mgcjag » Wed Jul 19, 2023 6:39 pm

Yes Christopher you are absolutely correct...but i can convince myself that i have then all spot on just by feel :bigrin:
Steve
69 S2 2+2 (sold) ..Realm C type replica, 1960 xk150fhc

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Spark
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#5 Re: Valve clearances

Post by Spark » Sat Jul 22, 2023 1:57 pm

Hi guys
Thanks for the replies much appreciated
As I have the covers off and have time I’m going to give it a go and see if I can get all at 0.013
May regret it after a few hours + but at least I will have my own satisfaction of believing they are close

thanks again
Phil

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abowie
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#6 Re: Valve clearances

Post by abowie » Sun Jul 23, 2023 1:34 am

If it's not noisy and runs fine I'd leave it alone.

Setting the clearances with the head on always carries the risk of accidental valve damage or dropping things into places they shouldn't go.
Andrew.
881824, 1E21538. 889457. 1961 4.3l Mk2. 1975 XJS. 1962 MGB. 1979 MGB.
http://www.projectetype.com/index.php/the-blog.html
Adelaide, Australia

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DWW
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#7 Re: Valve clearances

Post by DWW » Sun Jul 23, 2023 11:57 am

Sound advice 👍
Danny

1962 S1 3.8 FHC (1012/1798)
2015 Range Rover Sport SVR
"Experience is something you don't get until just after you need it."

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