<VV> Hot Idle Question

[Bill H.]

                                              B"H

Thanks Jim.  Is there any problem letting it wait for summer? Do the valves have to be re-adjusted after the springs are replaced?  If so, I just might take on replacing the o-ring seals at the pushrod tubes, altho I think mine are Viton.

Thanks again...Bill Hershkowitz

--- On Thu, 6/25/09, James Davis <jld at wk.net> wrote:

> From: James Davis <jld at wk.net>
> Subject: Re: <VV> Hot Idle Question
> To: "Bill H." <gojoe283 at yahoo.com>
> Date: Thursday, June 25, 2009, 12:08 AM
> This has been discussed several times
> in the 14 year history of VV.   The best
> answer is you are encountering the start of valve bounce or
> float.  This occurs with the 891 can (110 and 140
> engines) around 3,700 rpm with new valve
> springs.   As the valve springs are exposed
> to numerous heat cycles they weaken, lowering the rpm where
> the bounce starts to occur.   When the lifter
> quits following the cam profile exactly  (this is the
> end result of valve bounce) the lifters pump-up to
> compensate (called valve float).  You do not notice
> this at speed as the engine rpm is sufficient to mask the
> problem.   A the lower rpms the intake being
> held slightly open and this is the cause of the
> problem.  Why the intake valve...well it is the
> heaviest and since both the exhaust and intake valve springs
> are the same, the heavier valve has the problem
> first.   Usually a new set of valve springs
> will cure the problem.  The valve springs can be
> changed without pulling the engine or head.  It usually
> take about one hour per head to change the springs.
> Jim Davis
> 
> Bill H. wrote:
> >               
>                
>                
>         B"H
> > 
> > Hi all...I noticed something interesting about my
> car...when I drive locally in the city, my engine runs nice
> and smooth.  However, after a long drive, say 50-100
> miles on the highway at a steady 55-65 mph, when I come
> home, I notice the engine runs noticeably rougher.
> > 
> > After that, if I drive locally, it smooths out
> again.  Anyone experience the same thing?  Car is
> a stock 1969 110 with Powerglide.
> > 
> > Thanks in advance everyone...Bill Hershkowitz 69 Monza
> 110 PG
> > 
> >   
> 
>