[Healeys] oil pressure relief valve

[Chris Dimmock]

And what if the spring is 50 years old, and has lost it's tension, and  
opens at 20 lbs?? And what if the valve isn't seating and sealing in  
the block??

Sent from my iPhone

On 29/09/2010, at 5:07 PM, "lists" <lists at brits-n-pieces.com> wrote:

> But what if the spring has mistakenly been designed to open the  
> relief valve at 40psi (meaning it is too short, as mentioned by  
> someone else previously)? I'd say the washer would cure the problem.  
> What do you say?
>
> Eric
>
> You are absolutely correct!!
> There is NO fallacy in your thinking.
>
> Michael Salter
>
> On Tue, Sep 28, 2010 at 11:42 AM, <healeymanjim at hansencc.net> wrote:
>
>> i am having trouble understanding how increasing the spring  
>> strength in the
>> oil pressure relief valve will increase oil pressure.  this spring is
>> calibrated to keep the oil pressure in the engine to below aprrox  
>> 60 psi.
>> when the oil is cold and the pressure is above that, the spring is
>> compressed and excess oil returns to the sump.  once the oil heats  
>> up enough
>> to allow the pressure to decrease below 60 psi the relief valve  
>> closes,
>> never to enter the equation again.  increasing the spring strength  
>> would
>> only cause the relief valve to come off the seat at a higher  
>> pressure, i.e.,
>> 70 psi with cold oil.  i cannot see where increasing the strength  
>> of the
>> spring would do anything to increase the pressure of hot oil, say  
>> from 35 to
>> 45 psi.  where is the fallacy in my thinking?   hjim