Lost Oil Pressure - What to do?

[PurpleBeeper]

I was driving home and had pulled up in front of my house (at idle) and heard "rattle, rattle" (440 engine) & saw my oil pressure had dropped to zero, so I shut the motor off. Thank God I was in front of my house. It sounded like the valve gear rattling & not the deep "clunk, clunk" of a rod/main bearing (I'm hoping anyway). The engine did not seem to have any type of misfire.

These are the things that I can think of that could cause this problem.
1. spun main bearing
2. spun rod bearing
3. spun cam bearing (#4, right?)
4. leaking line going to the oil pressure gage
5. oil pump failure
6. REALLY low oil (was 1-1/2 qts. low per aftermarket dipstick). I don't think the pickup sucks air until about 3 qts. low (?)
7. Oil pump failure
8. sheared off the hex end of the oil pump/distributor gear

I'm afraid to even crank the motor until I find the problem. Obviously I don't want to pull the engine if I don't have to.

How do you guys suggest I go about fixing this problem? What order should I check everything? Can I see the hex end of the distributor/oil pump drive if I just pull the pump off? How can I tell if the pump went bad?

Any help is appreciated. Thanks in advance.

 

[lewtot184]

if the oil pick-up fit tight against the pan during assembly they will crack and break up at the the threads. checking the intermediate shaft is easy. taking the pump off and checking it is easy.

 

[Mike67]

Hate to hear that...
You can pull your sending unit and pipe in an air line set your regulator at 40 psi and see if it registers, remember you still need to ground the sending unit...
I would drain the oil and see how much you actually have.I never trust after market dipsticks unless I've compared them to an original, especially if you have an after market pan...cut open the filter and see if any shiny bits wink at you.
I'm not sure what the spec is on the rotor clearances are but I'm sure someone here can tell you. Might pull the distrib and look at the end...
Good luck

 

[khryslerkid]

You can pull your sending unit and pipe in an air line set your regulator at 40 psi and see if it registers,

He stated that it's rattling. Definitely no oil pressure.

Make sure your oil level is good.

You could drain the oil, take a light and look inside the pan for the pick up tube, or fish around in there with a stiff wire to find out if it's broke off.
Try changing your oil filter too. I've heard of the oil filter failing and causing oil pressure loss. Go to napa and get a Wix filter. It could be as simple as this.

If that doesn't fix your oil pressure, then you can check out the oil pump. Remove the relief valve and check for dirt or something holding the valve open. You remove it from the outside of the pump without removing the pump itself.

If it looks ok, then you can pull the distributor, then the oil pump drive shaft and check it for not being twisted off. Or pull the pump like Lew stated.
If it's ok, then pull the oil pump. And check it out.

You can decide in which order you would like to go through checking causes. Think simple first so not to cause yourself extra work and money.

 

[Daves69]

IMO, Running a short time with zero oil pressure will not be good on those bearings.

Before restarting I'd verify oil level is full. Pull the distributor and intermediate shaft. Get a Primer shaft with a 5/16" hex on the end into the pump gerotor shaft. Run it CCW with a decent reversible drill and see what oil pressure shows on a mechanical gauge.

 

[moparwacko]

If all else fails (other things mentioned here) and you still can't find your problem...make sure it's full of oil, pull distributor, and run the pump with a drill. Look up priming. You'll know quick if it builds pressure, remember CCW, and have a good grip.Use a good mechanical Guage. no pressure ? now you can start tearing into it

 

[moparwacko]

I must have been replying while you were posting, great minds ......

 

[mdroadrunner]

I bent a pushrod once and the lifter popped out of the bore.... Zero oil pressure... Pull both valve covers and check.....

 

[PurpleBeeper]

Thanks guys. I've worked so damn hard to get this car back on the road after 20 yrs. of sitting. I've gotten similar advice on another site. Over the years I've "lit up" a couple motors on nitrous, but never at idle.

 

[Cornpatch MO]

I bent a pushrod once and the lifter popped out of the bore.... Zero oil pressure... Pull both valve covers and check.....

I was about to post this same advice..happened to me once........................MO

 

[Lets Roll]

I lost a 360 once from a clogged oil filter . But that was well worn engine and it was believed carbon fell down from under the manifold and valve covers and clogged things up.

 

[mr. b]

I had that happen to me once the pressure relieve valve stuck in the oil pump

 

[Yatzee]

I was driving home and had pulled up in front of my house (at idle) and heard "rattle, rattle" (440 engine) & saw my oil pressure had dropped to zero, so I shut the motor off. Thank God I was in front of my house. It sounded like the valve gear rattling & not the deep "clunk, clunk" of a rod/main bearing (I'm hoping anyway). The engine did not seem to have any type of misfire.

These are the things that I can think of that could cause this problem.
1. spun main bearing
2. spun rod bearing
3. spun cam bearing (#4, right?)
4. leaking line going to the oil pressure gage
5. oil pump failure
6. REALLY low oil (was 1-1/2 qts. low per aftermarket dipstick). I don't think the pickup sucks air until about 3 qts. low (?)
7. Oil pump failure
8. sheared off the hex end of the oil pump/distributor gear

I'm afraid to even crank the motor until I find the problem. Obviously I don't want to pull the engine if I don't have to.

Oil is sucked in the pump and pressured out so the first thing to do is to remove the dizzy and use a priming rod to spin the pump just like the first time you assembled the engine. Thread a mechanical gauge in one of the pressure ports on the back of the engine, remove both rocker covers and with the proper amount of oil in the pan spin the prime rod with a drill. You should easily reach 50 psi and see if oil comes out the rocker rods to the rockers. Mopars oil from the top down meaning the crank gets oiled last. Draw your own conclusions from your observations.
No oil up top means no oil down below. No oil at all means bad pump or buggered pickup.
How do you guys suggest I go about fixing this problem? What order should I check everything? Can I see the hex end of the distributor/oil pump drive if I just pull the pump off? How can I tell if the pump went bad?

Any help is appreciated. Thanks in advance.

 

[Daves69]

Here's the flow........................

 

[mopar 3 B]

You are going to pull and disassemble check and replace anything and everything damaged. It will be your only insurance of future longevity. Yes its a pain but will you ever trust it again with the thought what was missed that is waiting to happen.

 

[Dennis H]

Car was driven 1 1/2 quarts low? Mine sprung a valley pan leak one time and started to rattle. Was almost 2 quarts low and did not know it. Holds 5 quarts. Goofy **** chrome dipstick shows full when oil is visible through the second L in FULL as determined by checking at oil change time. Was on a roadtrip hammering it. Put 2 quarts in at Chevron in Coalinga and it quieted it down. Factory gauge showed good pressure, drove home. Dodged bullet. Got lucky.

 

[PurpleBeeper]

Thank God! I worked on the old Road Runner this weekend and found out the engine is NOT SEIZED, so apparently I shut it off in time. It was just super low on oil. The dipstick read 1-1/2 qts. low, but after calibrating it (aftermarket), it turns out I was 2-1/2 qts. low on oil. I filled it up with fresh SAE30 & a new filter and it was getting 80psi cold at 2000 rpm. Thanks everyone for your support!

 

[Dennis H]

Thank God! I worked on the old Road Runner this weekend and found out the engine is NOT SEIZED, so apparently I shut it off in time. It was just super low on oil. The dipstick read 1-1/2 qts. low, but after calibrating it (aftermarket), it turns out I was 2-1/2 qts. low on oil. I filled it up with fresh SAE30 & a new filter and it was getting 80psi cold at 2000 rpm. Thanks everyone for your support!

Good news. Is it quieted down?

 

[Ranger16]

Hard to imagine pressure going to zero with 2.5 qts still in the motor.

 

[Dennis H]

Ag

Hard to imagine pressure going to zero with 2.5 qts still in the motor.

Agreeed. But my circumstance was pretty similar. Maybe showed 1 pound and rattled.