Part of it is to allow for expansion of the parts when hot. That will close
down the clearances.
A couple of other reasons for not running zero lash would be excessive wear
from the constant contact between cam and follower (or rocker), and the fact
that as the valve sinks further into the valve seat with wear, the valve
wouldn't completely close.
Gordon Glasgow
Renton, WA
www.gordon-glasgow.org
> -----Original Message-----
> From: owner-datsun-roadsters@autox.team.net
> [mailto:owner-datsun-roadsters@autox.team.net]On Behalf Of
> Dat2000srl@aol.com
> Sent: Thursday, January 30, 2003 9:23 PM
> To: datsun-roadsters@autox.team.net
> Subject: Re: Rule of 9
>
>
> I have often pondered the question of why there is a gap at all?? I know
> there is a reason for everything, so what damage would occur if
> the gap is
> slightly less than the tolorances given in the book. I would guess that a
> greater gap would cause the valves to open less... and also incur a more
> violent rapping to the stem to rocker arm. Any input or responses
> welcome. I
> always favored the tightest gap within the tolerances
>
>
> Larry Coughlin
> 68 1600 U20
> 69 2000 Mikuni B cam
> 70 1600 parts car
/// datsun-roadsters@autox.team.net mailing list
/// Archives at http://www.team.net/archive
|