Bypass

[94 formula]

Is the oil bypass valve something that lets oil pass without going through the filter when the pressure is higher? If so whats the pressure in the LT1?

 

[Patman]

When the oil filter gets clogged or when the oil is very cold, the bypass unit will keep oil from going into the filter.

I"m not sure what the LT1's setting is though, I tried to find out that info myself about a year ago and even guys with the service manuals couldn't find any info on it.

 

[Ken2]

94...

Just to be clear, for the bypass we're talking about the difference in pressure between the oil filter inlet and it's outlet, not the oil pump's output pressure.


Ken

 

[Steve S]

The oil filter bypass valve located in the block or the oil filter depending on the make or the model of the filter or engine is a pressure differential valve. If the engine has been just started there is oil flow on the pump side of the filter but not the oil passage side, there will be an increase in oil pressure due to the restriction of the filter element. This will cause a differential of pressure which lets use 10 psi.as a figure ,the valve will open allowing oil flow to the oil passage with a minimal drop in flow. Now when the engine is cold and the oil is thick the valve may stay open untill the. oil warms up. Or if cruising down the road we decide to pass a slow moving truck we do a down shift the engine rpm increases along with the oil flow .The flow increase causes an increase in oil pressure due to the restriction of the oil filter element and when the difference is 10 psi the valve opens allowing a minimal drop in oil flow to the oil passage. When the pressure becomes equalized the valve closes. I'm not sure but i'll bet on sone filters stay in bypass more than others due to quality, oil viscosity ,crud in the filter, engine operation and more things than I know about. I also don't know what the psi rating for the valve is but i,ll bet it may not matter because the rating on aftermarket filters varies.