440 no oil pressure

[Daves69]

Well today I pulled the pump off to have a look at it and the pump looked fine. But did notice the cap for the pressure valve was a little loose. Tightened that a put it back on. Primed it and I was a getting some pressure on the gauge. But ran out of time, I'll start it up next weekend and see if the pressure is back to normal. FYI, I have an aftermarket milodon external oil pump.

I could be wrong but I don't think "a little loose" would translate to zero pressure. Then too, with no broken intermediate shaft, what's left? Rotor possibly spinning on the rotor shaft similar to having a spun prop on a boat? Maybe you should mark it before you fire it up again.

 

[mkbubs]

Today I finally got out there and was able to mess with the car. I tried turning the motor over and I'm still not registering any oil pressure. I guess I just don't understand how I can have good pressure to no pressure at all. Even if you say changing the spring in the pressure valve might work.

 

[Daves69]

Today I finally got out there and was able to mess with the car. I tried turning the motor over and I'm still not registering any oil pressure. I guess I just don't understand how I can have good pressure to no pressure at all. Even if you say changing the spring in the pressure valve might work.

If your sure the intermediate shaft is sound your running out of potentials. Plugged pickup screen, cracked pickup tube sucking air, stuck relief, or low oil level.
I worked at a place that manufactured hydraulic high pressure pump gears. Many of these gears were pressed on shafts. We did have failures where assemblies did not meet torque spec in a fixture (shaft spun). I'm sure it's possible with gerotors as well if not pinned or keyed. I'd swap in a new pump.

 

[mkbubs]

also out of curiosity, what is the thread size on a 440 block for the oil pick-up? currently running an external oil pump system, and if i need to take off the oil pan one more time, im gonna swap it out to a stock style. thanks

 

[Dennis H]

Don't know the thread size, but mine was sudden and complete loss. Blocked pick up.

 

[Daves69]

also out of curiosity, what is the thread size on a 440 block for the oil pick-up? currently running an external oil pump system, and if i need to take off the oil pan one more time, im gonna swap it out to a stock style. thanks

Stock is 3/8" pipe. It can be modified to 1/2" pipe for the hemi pickup.

 

[66Satellite47]

I just realized you're talking Milodon external suction pump. Have you checked the fittings, O rings, suction hose/tube etc? If I recall correctly there's an O ring or two on the relief spring assembly.

 

[TetanusShot]

Maybe the culprit is the oil pressure gauge itself. Also, if the oil filter is still empty from inspecting it, turning the motor over a couple times wouldn't show any pressure until it filled up again anyway. My two guesses, good luck!