HELP NO OIL PRESSURE

[soda4u2]

LITTLE HELP PLEASE!! BOUGHT A 70 440 CHALLENGER LAST WEEK, CAR HAS BEEN SETTING ABOUT 5 YEARS!! CHANGED PLUGS, OIL , FILTER, CLEANED TANK, FUEL FILTER, GOOD GAS!! CAR FIRED UP FIRST TRY. GOOD 65-70 LBS OIL PRESSUE. I DROVE THE CAR AROUND THE BLOCK A FEW TIMES TRYING TO FIGURE OUT WHAT ALL WAS NEEDING TO BE DONE. DROVE THE CAR A COUPLE MILES LAST NIGHT ( OIL PRESSURE WAS FINE). STARTED THE CAR THIS MORNING , STARTED RIGHT UP ON FIRST TURN. NO OIL PRESSURE AT ALL. MANUAL GAUGE SO I PULLED THE LINE FROM THE BLOCK, TOOK COIL WIRE OFF, TURNED ENGINE OVER, NOTHING CAME OUT, SWAPED OIL FILTER AGAIN, NOTHING, REMOVED SPRING AND SEAT FROM SIDE OF OIL PUMP( NOTHING WRONG THERE).  I'VE ORDERED A NEW OIL PUMP. THE ONLY THING I CAN THINK OF IS THE PUMP WENT OUT OR THE PICK UP CAME OFF THE BLOCK!!! IS THERE SOMETHING ELSE I MIGHT BE FORGETTING?? IT'S BEEN 35 YEARS SINCE MY LAST MOPAR!! I'M A LITTLE RUSTY!!!! ANY ADVICE WOULD BE GREAT!!!! THANKS- JIMMY

[Strawdawg]

Other than not using all caps, I would be sure the oil pump drive is turning the pump and did not break off

[soda4u2]

thank you

[Strawdawg]

It's kinda unlikely that it would have pressure when you shut it off and then, the next day, have none unless something broke.

You checked the high pressure by pass valve in the side of the pump and if the valve under the spring moved up and down freely in its bore without being sticky and had no rust on it or debris under it, it would seem to be working.

The likely thing would be the drive shaft is not turning the pump when the distributor is turning.  You will have to pull the distributor and the gear that drops into  the valley so you can check the shaft.

It's not unknown to shear at the bottom part of the drive....I know the feeling well of buying something and getting it home and then it stops working....

[72cudamaan]

    And you're right, the pick up might have come off. But it is unlikely to almost impossible
that the oil pump suddenly went out just like that.

[anlauto]

It's kinda unlikely that it would have pressure when you shut it off and then, the next day, have none unless something broke.

You checked the high pressure by pass valve in the side of the pump and if the valve under the spring moved up and down freely in its bore without being sticky and had no rust on it or debris under it, it would seem to be working.

The likely thing would be the drive shaft is not turning the pump when the distributor is turning.  You will have to pull the distributor and the gear that drops into  the valley so you can check the shaft.

It's not unknown to shear at the bottom part of the drive....I know the feeling well of buying something and getting it home and then it stops working....

This is actually a good theory.....The oil pump could have jammed causing the drive to snap off...cam and distributor are still running  Try removing the whole oil pump off the block to see what you find...

[soda4u2]

I've just not had a motor be fine when you turn it off. Then start it the next day and no oil pressure. no indication of anything wrong! Such is life!! Thanks for all your Advice!

[FY1Cuda]

I once had a little piece of teflon tape plugging up the hole in the sender unit so it read no pressure.  Is it possible that some little piece of something has plugged up the fitting where the oil line comes out?

[soda4u2]

OK- here's what I've done. Pulled the oil connection out of the block, turned over engine- nothing came out. Pulled the oil pump, seems to be free of any obstruction, turns smooth, no play or wear. Pulled the distributor and gear and shaft assembly. Gear  still has pin through shaft and there is no wear to gear or wear on gear on the cam! NOW WHAT??

[anlauto]

What was your first sign of no oil pressure ? Was it just the gauge or did the motor get real loud with ticking and knocking ?

[Strawdawg]

This is actually a good theory.....The oil pump could have jammed causing the drive to snap off...cam and distributor are still running  Try removing the whole oil pump off the block to see what you find...

check to be sure the shaft is still pinned....and if it broke, then pull the pump and see if it will turn...I was also thinking it may have jammed as well

[soda4u2]

Stuck a allen wrench in the pump. turns free and smooth with no slack!

[soda4u2]

also when I put the gear and shaft back in the  gear drops back in place beside the cam gear. It is tight and will not turn. it is engaged with the cam gear. I'm thinking the port for oil pressure line is plugged or the pickup came off the block, I don't know what else to check??

[Strawdawg]

You can stick an air hose chuck in the hole, I guess and try to blow back thru it.  You can pull a valve cover and see if it is getting oil at the rockers... just let it idle for a couple of seconds to see what happens.  Don't rev it which puts a load on the bearings=or unplug the coil and crank it over a few times

Or you can pull the gear/shaft out and make a drive to spin the pump with and drill and see if it gets hard to spin as it should if it is making oil pressure.

If no oil up top or the drill spins freely in the pump, then you will have to pull the pan and check the pick up but I think it is unlikely to have come out given that it is threaded.

[spamtank]