Low oil pressure?

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You mean the hole in the intake next to the distributor? That's farther that 7 1/2 inch to the main cap?
 
Cope said:
You mean the hole in the intake next to the distributor? That's farther that 7 1/2 inch to the main cap?
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No not a hole in the intake. It is a hole in that rear China Wall that your oil pressure sending unit screws into next to the distributor.
 
Did you put a gasket between the oil pump and the main cap, maybe it blew out. I never use them for that reason.
 
Not sure about the gasket.

Dam I wish I could pull the oil pan with the engine in the car. Frickin MOPAR.....

:)
 
You can take the oil pressure sending unit out. Then take your dipstick and stick down in that hole and where it stops Mark that pull it back out and measure it.
If that measurement is over 7 and 1/2 in then that plug is not in place.
 
You can, just drop the center link and it should come off, maybe unbolt the front motor mounts and jack it up a little.
 
jimjimjimmy said:
the plug under the rear main cap will not effect oil pressure it directs oil thru the filter
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Well, it might increase pressure but it does as jimjim says.... diverts the pump's oil output to the filter inlet passage. If the plug is out, the oil goes straight into the passenger side oil gallery. It won't loop back through the filter; the pressure where the plug was supposed to be will be a fraction of a psi higher than at the top where the oil filter outlet passage joins so oil won't flow backwards. I'd expect it to slowly purge the air out of the filter and then the filter will be just a static 'wart' on on the oiling system. Any oil drain back protection from the filter will be lost.

Seems like we have all been through this before somewhere... LOL deja vu all over again...
 
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If that plug is not in there and the engine is pumping oil then let's say for example the oil pressure gets up to 60 pounds. The bypass in the pump opens and drops the pressure in the pump so then by not having the plug in that line the oil goes back to the filter and it stops going up to the top of the motor then pressure drops bypass kicks out oil pressure builds up again feeds the top of the motor. Until pressure builds up bypass opens in the pump and once again the oil pressure drops.
 
Jadaharabi said:
If that plug is not in there and the engine is pumping oil then let's say for example the oil pressure gets up to 60 pounds. The bypass in the pump opens and drops the pressure in the pump so then by not having the plug in that line the oil goes back to the filter and it stops going up to the top of the motor then pressure drops bypass kicks out oil pressure builds up again feeds the top of the motor. Until pressure builds up bypass opens in the pump and once again the oil pressure drops.
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I think it's more like if the pressure bypass spring is set at 70 psi the plunger starts compressing the spring as the pressure goes up, when it gets high enough it bypasses and the pressure stays at that pressure, it doesn't go up and down. When the pump slows down enough to close the port then it just goes down in pressure. If the plug is not in the block the oil will flow straight up to the main galley and through the motor but not through the filter, with the passage plugged it goes through the filter then to the main galley. End of story.
 
Bottom line check and see if the plug is in there. If it's not your oil system will not function properly.

And that is the end of the story.
 
a la Deja Vu. from a previous thread- If you hook a garden hose to the front and back faucets of your house, turn them on, how is that gonna affect pressure at any of you interior faucets?
 
inertia said:
a la Deja Vu. If you hook a garden hose to the front and back faucets of your house, turn them on, how is that gonna affect pressure at any of you interior faucets?
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A drop in volume.

edit after re read

This would be a looped system so if you open a faucet anywhere in the house you could actually be fed from both sides of your water system. We did this in the desert in a Housing Development. It helps to maintain pressure throughout the system.
 
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inertia said:
a la Deja Vu. If you hook a garden hose to the front and back faucets of your house, turn them on, how is that gonna affect pressure at any of you interior faucets?
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Well first it goes around and around then it make the rest of the house go up and down.
 
Jadaharabi said:
If that plug is not in there and the engine is pumping oil then let's say for example the oil pressure gets up to 60 pounds. The bypass in the pump opens and drops the pressure in the pump so then by not having the plug in that line the oil goes back to the filter and it stops going up to the top of the motor then pressure drops bypass kicks out oil pressure builds up again feeds the top of the motor. Until pressure builds up bypass opens in the pump and once again the oil pressure drops.
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The restrictions that cause pressure buildup are >95% in the motor and do not change with the filter bypassed. So, there is always positive pressure from the pump on both the passages to and from the filter, with or without the plug. The oil cannot 'stop going to the top' of the motor since there never is any lower pressure in the filter area to which it can flow.

The air in the filter may provide some 'softness' in the pressure regulation until the air bleeds out of the filter; that part I can see. Some oil will want to slowly feed through the filter and will bleed it out any air eventually.
 
Cope, I think you could be sucking air, is your pickup new or used, I also seen one that had a crack in the threads were the pickup screws into the pump aerating the oil causing a low oil pressure at low rpm's.
 
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