Changing oil pumps, how to prime it

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I'm switching out the oil pump on my 2.4. I just poured a small amount of oil in it then let it drain out the pump. Then I plan on removing the coil pack and fuel pump relay and cranking it before starting. Will this be good enough? I figure when you stop the car or drain the oil all the oil seeps out of the pump anyway so it should be fine. I was told to stuff it with motor rebuild grease but I heard this does weird stuff in oil so I don't want to do that. I'm kind of worried though, I heard if theres air in the pump it will cause cavitation? Whats cavitation?
 
I don't know what the contemporary procedure is (as in preferred) but packing it with petroleum jelly was the common technique for oil pumps that you couldn't prime with a drill. It allows it to produce the suction head required to draw the oil from the sump.



look down a bit.
 
What engine are we dealing with, something archaic or something fairly new.

If it's new, I would do a short period of cranking without spark/fuel and that should be good enough before starting the car normally.
 
I recently upgraded to a DCR oil pump while doing a Timing Belt job on my srt4, to prime the pump I unplugged the coil pack and turned the engine over about 5-7 seconds at a time and I did that about 7 times. Everything works great.
 
Originally Posted By: TurboLuver
I recently upgraded to a DCR oil pump while doing a Timing Belt job on my srt4, to prime the pump I unplugged the coil pack and turned the engine over about 5-7 seconds at a time and I did that about 7 times. Everything works great.


Oh what a coincidence, same car and same oil pump
 
If I am not mistaken the DCR pump comes with an instruction sheet.
You doing a timing belt job too?
 
yeah I am, but the instruction sheet is a joke. It says prime the pump and torque it to 20 ft/lbs. Thats about it.
 
I guess I really didn't look at the sheet, I asked a friend who is a mechanic at a Dodge dealer. What kind of belt kit are you using?
 
I'm not using a belt kit, just a goodyear timing belt and DCR pump
 
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Ahh I see, but why are you changing the belt though? I have 70k and the only reason I did the TB job was that I had a crank seal leaking and I figured I was already in there + I was getting close to the recommended TB interval anyway.
 
Petroleum jelly is the stuff to prime an oil pump....grease is not recommended,but I've not had any problem with grease either.Apparently grease won't dissolve in the oil,could block the foofoo valve and destroy the engine....fortunately we don't have foofoo valves here.I also sometimes use thick goopy stuff like STP,Wynns or Moreys as an assembly lube,and it is good as an oil pump prime too.
 
I don't know how they define grease but engine rebuild grease is petroleum based and dissolves in oil and I think white lithium grease is the same thing. Jelly, grease I don't know

I'm changing the timing belt because I'm doing the oil pump so I might as well. A couple years ago I decided I needed the DCR oil kit for some reason, I think it's probably overkill for my horsepower levels but oh well, I've had the pump sitting around and it would be a waste not to put it in. tensioner and water pump are both 75 bucks so I'll do those in another 60,000 when I have to do the timing belt again.

Nobody seems to be sure whether the TB interval is 60,000 or 105,000 on our cars.
 
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Originally Posted By: TurboLuver
Ahh I see, but why are you changing the belt though? I have 70k and the only reason I did the TB job was that I had a crank seal leaking and I figured I was already in there + I was getting close to the recommended TB interval anyway.


The crank seal that you had leaking, are you refering to the one in front of the oil pump that just presses in or is it something else that you have to remove the oil pump for?
 
If the engine/computer has a "flood clear" mode by flooring the gas pedal while starting, you could do that until the oil pressure light goes out, then the pump is primed..
 
Originally Posted By: 7055
The crank seal that you had leaking, are you refering to the one in front of the oil pump that just presses in or is it something else that you have to remove the oil pump for?


Yes, it's the front crank seal. Be sure you get it in there square because if not it will leak. I borrowed the seal installation tool from my buddy, but you can use a socket.
 
I use STP. IT's sticky and tacky so it will form a seal between the gears and allow the pump to pull the oil from the pan quickly. The 1/2 oz in the pump will be a non issue once mixed with the oil.
 
It probably depends, mine came unprimed and said it needed to be fully primed before starting. I just cranked it without fuel and spark. I knew it was working because it sucked up a half quart of oil out of the pan during cranking.
 
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