valve springs

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unklpat
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valve springs

Post by unklpat »

I'd like to know how many of us have replaced their valve springs during a head rebuild. Please choose between R16, or U20. And bonus points if their machinist advised it, or if you just did it. Pat
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Nissanman
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Re: valve springs

Post by Nissanman »

Well, once I got the valve springs out on the bench from my G15 (sorry!) I noticed their free length was all over the place :roll:
So, I had my Shop select some which were used but passed the compression test and were identical in free length.
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Solex68
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Re: valve springs

Post by Solex68 »

I did replace my springs for two reasons:
1. I did not know the history of the head
2. My head was being rebuilt with a high performance Rebello cam and because my head was being rebuilt by Rebello.

Honestly I would have done it for reason #1 alone.
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unklpat
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Re: valve springs

Post by unklpat »

Thx Greg, I think I'd leave it up to the machine shop, as to what they recommend. I'd change them too, but sometimes older parts are stronger than new ones. Pat
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spl310
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Re: valve springs

Post by spl310 »

I think that at a minimum, the springs should be checked against the specs for the cam that you are using.
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Solex68
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Re: valve springs

Post by Solex68 »

unklpat wrote: Wed Sep 08, 2021 2:56 pm Thx Greg, I think I'd leave it up to the machine shop, as to what they recommend. I'd change them too, but sometimes older parts are stronger than new ones. Pat
That is a good point.
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keith0alan
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Re: valve springs

Post by keith0alan »

When I am doing a head I do a compression and free length check and replace any not up to spec.
unklpat
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Re: valve springs

Post by unklpat »

Thanks to all who responded. I'm of the opinion that the machine shop will decide if valve springs should be replaced. We all know that not all new parts are up to the standards of old parts. Pat
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