<VV> Replacing Oil Pressure Regulator Spring

[Frank DuVal]

I'll take a stab at the explanation. Spring below includes the operation 
of the plunger in the description. The spring alone cannot  dump 
excessive oil pressure, the plunger does by exposing other passages in 
that rear cover.

The spring regulates oil pressure, by bypassing excess oil back to the 
sump if the pressure is too high.

Oil pressure will be greater when the engine is running higher revs.

At idle, the available oil pumped through the passages of the regulator 
is less than at higher revs.

Since the spring regulates to some pressure that keeps the light off at 
revs above idle, and there is less oil at idle,  the spring is not 
regulating the pressure below the light turn on setting at idle. There 
is simply not enough oil supplied by the pump to turn the light off. The 
regulation setting is determined by the spring, but that setting does 
not change with pressure of the oil. But when the oil pressure is below 
the setting of the spring, the spring cannot "pump" the oil pressure to 
a higher level. The spring can only lower oil pressure.

So if the spring was weak and bypassing oil pressure at a low setting, 
that should also happen at speed, not just at idle.

Flame suit on awaiting people who can write better to respond!

Frank DuVal

On 3/23/2012 1:03 PM, Joel McGregor wrote:
> Hate to disagree but it could possibly be the spring.  I've had it happen with the exact symptoms he has.  Springs do settle especially after so many years and so many heat cycles.  Mine happened 20 years ago.  His light is coming on but how would the light being on or off tell you that it could or couldn't be the spring?