hum wierd i have had alot of engines and pulled and installed alot of vehicles including the same year and vehicle my LG4 305 came from and never seen a pipe plug in the oil sender unit hole from factory

i am confused as to where the oil pressure signal comes from if this port is plugged

there is no oil pressure sender anywhere, just a two spade switch jut above the oil filter and thats it

anyone have any idea ?

the 83 caprice classic it is from would have had an oil warning light and not a guage


i swear every '80s caprice classic LG4 car i have ever had has had an oil sender unit and not plugged off


wierd.....

 

That it is by the oil filter, you can get oil pressure from there or behind the intake by the dist.

 

in my 88 the port above the oil filter is used to cut the fuel off if there is no pressure.

 

There is also an oil pressure port up on top of the block, at the back, just to the driver's side of the distributor. GM cars used that port for many years on many cars before they started to favor the port just above the oil filter.

Just take out the plug, screw in the proper oil pressure sender for your car and you'll be good to go.

 

yeah ill have to remove the plug up there and use it but i just couldnt ever recall it ever being plugged from factory like that

hum

interesting

isnt the one by the oil filter just a switch and not a sender

its not very big like a sender is

and its two spade

or is it unique for dummy lights only, in which the car this engine came from had



thanks

 

They usually used the port by the oil filter for the 'dummy' switch that shutdown the electric fuel pump on loss of oil pressure. The one up by the dizzy was mainly used for the oil pres gauge.

But it doesnt matter which one is used for what. Some of them even have a T fitting and run both units off one port.

Their is also a port just north of the cam timing gear on the front of the block. that one doesnt have much use though, except for test purposes.

 

The oil pressure switch doesn't shut off the fuel pump on loss of oil pressure. It powers the fuel pump in case of a fuel pump relay failure.

The port on the front of the block is present on older blocks, but not newer ones.

 

damon..i have this oil pressure sender unit on top of the intake manifold...it has two spade terminals...is one ground and the other goes to the tan wire? my inst. panel has an oil gauge. thanks.