Big Block oil pumps

['69Net]

Hey Guy's,
My oil pump on the 440 seems to have died? any idea's where to look 1st? I'm thinking intermediate shaft has stripped?
The car will start..so it's not the dissy.

Only been sitting for 2 weeks while I sorted the electrics, then when I fire it up, zero oil pressure.

Getting abit frustrated with the old Girl.:angryfire:

 

[WP29440SE]

are you sure it isnt the gauge? electric gauge ? manual? check there first . you can pull out the relief spring and clean it all up and make sure it isnt gooped up.

its easy enough to pull the distributor and the shaft out to have a looksee

 

[RustyRatRod]

Does it have oil in it?

 

[lewtot184]

never seen a pump just fail. pull the distributor and check out the intermediate shaft. another possibility is a tappet flipped out into the valley. i've done this before. its caused by breaking a rocker or the push rod punching a hole in the rocker, sticking in the rocker, and letting the tappet pop out. trying a different gauge is a good place to start.

 

[Hemirunner]

Bypass stuck wide open

 

[tallhair]

Have you rebooted it?

Joking! that's what the IT guys always ask me and i know it's not helpful at all .. sorry

 

[RustyRatRod]

I agree. I have never seen an oil pump fail on its own, either. I have seen them fail, but only because something else caused their demise such as something getting hung up in them seizing them up. Since an oil pump spends its life either submerged in oil or pumping it, I think oil pump failure with no outside influence is very, very rare.

never seen a pump just fail. pull the distributor and check out the intermediate shaft. another possibility is a tappet flipped out into the valley. i've done this before. its caused by breaking a rocker or the push rod punching a hole in the rocker, sticking in the rocker, and letting the tappet pop out. trying a different gauge is a good place to start.

 

[Pistol Pete]

Myself, I wouldn't start it anymore until you find out what's up.

First off, I'd pull the sending unit and install a mechanical gauge (cheap one is fine) to be absolutely positive you have no pressure. Ground the coil output wire and turn the motor over to check.

If no pressure, next I'd pull the dizzy and inspect the intermediate shaft.

If that shows well, I'd move on to the pump and check the bypass as Hemirunner suggests.

 

[68 HEMI GTS]

Bypass stuck wide open

yep, that'd be my guess.

 

[Meep-Meep]

As mentioned it's easy enough to pull the dizzy and check the shaft. Also while you have the shaft out, and assuming the tip is not broke off, drop an oil pump priming tool in there and give it a spin with the rear galley plug removed. If you are moving oil the drill will bog down quite a bit and you should have oil all over the back on the block.

 

['69Net]

Thankx Guy's....odd isn't it? was working fine..from about 50-60psi at idle too zero...and yes it has oil..and an after market gauge...

How do I check the bypass?

cheers Steve...

 

[Meep-Meep]

The pump is hanging out there so you could just remove it. The bypass is also accessible by undoing the hex plug on the end. Of course that plug is under spring tension so be careful towards the last few threads.

 

[lewtot184]

As mentioned it's easy enough to pull the dizzy and check the shaft. Also while you have the shaft out, and assuming the tip is not broke off, drop an oil pump priming tool in there and give it a spin with the rear galley plug removed. If you are moving oil the drill will bog down quite a bit and you should have oil all over the back on the block.

this is what i'd do before taking the pump off.

 

['69Net]

Broken Hex on the intermediate shaft...

 

[RustyRatRod]

There is a kid over on FABO who just experienced failure of the INPUT female hex of the oil pump gear itself. Although it was on a small block. I forgot about that. The intermediate shaft was fine. Although he didn't find anything that had caused the oil pump to seize, That's what we both suspect. I have been helping him by phone do a top end job on his truck 318. He is DarTT over there and CorneTT over here. You might inspect there as well.