Please help!! no oil pressure after oil change!!

-
Z

Zwap

Well-Known Member
Joined
Mar 6, 2016
Messages
118
Reaction score
15
Location
Sweden
I have no idea what happened, I drowe to the garage and changed oil and filter and when I started the 383 -66 I've got no oil pressure!!! Let it idle for a minute or two but no pressure and I can hear that the lifters got no pressure.
This is the third time I changes oil and filter since last spring and never had any problem before.
Removed the new oil filter and it was completly dry, crank it over without the filter and no oil is coming from the pressure side.
I got no oil pressure meter, just the warning light but as I wrote, I can hear it got no pressure and the warning light is lightning.
Please help!!
 
Last edited:
Well the good news is that you can pull the pump and replace it externally.

You might have a crack in the pickup tube, leaking air.

Cranking it with the filter removed was a good plan......it removes head pressure (resistance) to the pump and renders the "easiest" pumping condition.

You might pull the dist. gear and see if you can prime with a drill.

There's an oil ring up in "on" the pump snout in the engine. These can fail
 
Turn the engine over by hand at the crank and see if the distributor is turning. If not, the shaft between the distributor and oil pump broke.

*** Didn't think that through! Distributor can turn, but the shaft to the pump may be broke.***

It can be a little messy, but I always like to put some oil in a new filter so there is less empty space to prime after an oil change.
 
the only chance to get oil pressure again..is to prime the engine with a electric drill... don´t start the engine until you have verifyed that you have OIL Pressure..

Greetings Juergen
 
Check the oil on the dipstick. If you forgot the drain plug, it is all underneath the car. Ask me how I know.
 
brasil said:
the only chance to get oil pressure again..is to prime the engine with a electric drill... don´t start the engine until you have verifyed that you have OIL Pressure..

Greetings Juergen
Click to expand...

Ok, thanks everyone!
What is the difference between prime the pump with a drill and canking the engine, I let it idle for a minute or two, wouldn't the pump get primed then?

There is oil in the engine and the drain plug is in place.
I tried to squirt oil in the pressure side of the pump with the filter off and when i crank the engine the little oil I manage to squirt in squirt out so I think the pump i spinning, but when that little oil is squirting out there is no more oil coming.
 
With the filter off there is NO restriction at the pump outlet. One of the filter ports IS the outlet of the pump. This is the "easiest" condition you can make for the pump. If it won't prime on the starter with the filter removed, then the next step is

1.....Check for gear / shaft damage. Some shafts can spin the gear on the shaft, and sometimes the allen can be stripped in the pump or on the shaft. Unless the engine is gummed up, you can walk the gear "up and out" of the cam gear with a screwdriver, then get ahold of it with coat hanger, etc "tools" annd pull it out.

2....Next try to prime with a drill, keep in mind it turns CCW on B/ RB engines

3....If that won't work, I would double triple check "what you put in" for oil ( was it REALLY oil?) and how much and what the level is.

4....If 1--3 doesn't give an answer, time to pull the pump, inspect gaskets and O rings pull the pump apart.

5.....And if 4 fails, you have a cracked pickup tube One last step before you get this far is to dump a "whole bunch" of extra oil in the pan and see if it will prime. And that too, might suggest a cracked pickup.

ARE YOU SURE about your pan capacity? I think my old 70 440-6 was seven quarts.
 
OK, thanks!
I'll try the suggestion you gave.
As for the oil, it's 20W-50 as I always use on this engine and when I drain it comes out little more than four quarts and the service manual for my engine says 4 quarts and if I fill a little more than 4 quarts i got the MAX limit on the oil stick so I think it's the correct capacity for my pan.
 
Did you make sure,the old oil filter gasket,came with the old oil filter,spinning off?..Have seen/done , watched other car guys ,do it.... Just ,a thought....And,what are you using,for an oil pressure gauge? (Highly recommend,a mechanical one.....)...
 
Probably the engine is gummed up, I couldn't walk the gear "up and out" of the cam gear with a screwdriver, so I go direct to point 5 and removed the oil pan.
This is what i found inte the pickup tube, do you think this could restrict the flow enough not to make the oil pump to suck oil?
I couldn't find any cracks or damage on the tube that could suck air into it and if I use copressed air there is full flow.
Could I use this pickup again or should I replace it with a new one?

Pickup_1.jpg


Pickup_2.jpg
 
* Are those metal pieces or hardened oil crud?

* I wouldn't trust the pick-up because there may still be pieces wedged in the screen that may eventually work their way out and through.

* I would confirm that the oil pump shaft isn't broken somewhere, stripped hex or pump cracked where the shaft goes into the pump. I'm a small block guy, but shouldn't removing the oil pump reveal the end of the shaft?

* Make sure the oil pump itself turns freely. Open up the pump and inspect the rotors for debris and/or damage. (Smaller pieces could have gotten through the screen.)
 
Cope said:
Maybe fill the oil filter so it can prime the pump?
Click to expand...
I have always filled a horizontal filter at least half. Others even more. IMO, filling the filter is the way to go as it can provide prime in your BB oil pump. Also, the more fill in the filter ahead of start up the less time it takes to fill the oil galleries.
 
Remove the oil drive shaft, I bet it is broken where it goes into the pump. I had a 383 where the valve seals became very old and made there way into the pump. A small piece made its way the gears in the pump and sheared the hex part of the drive shaft entering the pump from the remainder of the shaft.

Also, those shavings look like plastic timing chain parts - may want to confirm the timing chain and the valve seals..

Like what Locomotion suggested.....
 
Ok thanks!
It's not metal parts, they are far to light but I don't know were they are coming from but I have a feeling that's some old stuff that have been there for a while.
I've ordered a new pickup, oil pump and the prime tool, I'm going to remove the old pump and try to push the drive shaft from the pump side instead of trying to pull it out from the dist. side and then prime the new pump before starting the engine, hope it will work then.
So much trouble for a simple oil change...
 
As mentioned above, might be nylon timing gear pieces. I would definitely be pulling the timing cover off for a look.
 
Put a magnet to the debris an see what it picks up. How much in the pan ?
 
I can "bet" right now what happened. The timing sprocket came apart, and pieces of the thing got into the pump, and broke the drive to the pump.
 
Well, here some update:
The shaft is in perfect shape and the hex in the pump show no signs of wear.
The pump though shows signs of wear.
Otherwise there is no clue what makes the pump not to suck oil from the pan.
I hope a new pump and pickup will do it.

shaft.jpg


back valve.jpg


pump_1.jpg


pump_2.jpg


pump_3.jpg


pump_4.jpg
 
Last edited:
Pump O rings and gasket? There's an O ring on the pump snout
 
I"m still baffled as to what happened. Everything was fine, you changed oil and then nothing. (Thinking out loud)
 
I think maybe the bypass stuck open. Just my 2 cents worth
 
I'm thinking bypass has to get high enough pressure to make that spring compress far enough to open. Even if it did he should have some pressure cold I would think. Not sure he had any at start up with a dry filter. To me, nothing was being picked up at all.
The chunks from the strainer look to me like old hardened cork gasket and possibly timing gear chips.
I would take another look at that intermediate shaft and try to assure myself the shaft is not slipping. Also it's possible the gerotor shaft could have spun if something bound up the pump.
I would not install a "dry" filter.
 
You must log in or register to reply here.
-

Back
Top