2004 Dodge Hemi 5.7L no oil pressure.

[Greg36]

Ok I know there's going to be some that will help and some that will just be a jacka$$ but we have a 1957 Chevrolet BelAir that we have stuffed a 2004 Durango 5.7L hemi into. We had to have a oil pan built to fit the under carriage components therefore oil pan was off for some time, no oil in car for 8 months plus. Now we have pan on oil in pickup tube new gasket filled oil filter with oil plugged the two port holes on the passenger side of engine above oil filter fitted a T with sending unit and original sensor for computer on end of the T. We have tried pulling the sending off pulling the plugs to make the engine spin easier, spin engine backwards while having a line plumbed into where sending was located to suck oil into oil pump, thought was possible air locked, it didn't work. We tried loosening the oil filter cranking engine to see if oil was pumping no luck either. We tried two different oil sending units, two different oil pressure gauges, still no oil pressure. This engine was running and only has 12000 miles on it, and ideas need help, we have to pull all the suspension loose motor mounts loose jack engine up just to get the oil pan off, tired of doing this, and help would be greatly appreciated. I will add photos of what the T looks like and where we have it placed. Oh yeah and quite often I am a jacka$$ so if you have valuable info please post it.
thanks,
Greg

 

[CKH]

I have a suspicion the T you have the sender unit in may be the issue. Have you tried putting the unit directly in the block without the T? Or pull a valve cover off and turn it over to see if oil is pumping up there?

Edit: I just re-read everything and saw you loosened the oil filter to see if it was pumping, disregard my idiocy.

 

[Greg36]

We are now leaning towards replacing the oil pump. Man this is insane, all we have left is clear the hood, get exhaust and this car is done.

 

[NYCruiser]

What about the design of the pan? Hemi's have big 6 qt pans. Could there be a problem with the custom pan design? Did you have to mess with the oil pump pickup to get the pan on? Hard to believe the pump failed on a 12K motor. I'm thinking there's no pickup installed on it, or it fell off, or its leaking air.

 

[Redtruck-VA]

Sounds like the pump isn't primed, never heard of it not picking up if the pickup is submersed. You do have the pickup tube reinstalled from when the pan was off? Did it need to be modified along with the pan?
Neat project BTW...

 

[CKH]

What about the design of the pan? Hemi's have big 6 qt pans. Could there be a problem with the custom pan design? Did you have to mess with the oil pump pickup to get the pan on? Hard to believe the pump failed on a 12K motor. I'm thinking there's no pickup installed on it, or it fell off, or its leaking air.

^^^^This, I would like to see the pan and pickup tube design as well. Could also be something simple like the O-ring on the pickup tube where it goes into the oil pump. If the O-ring is damaged or non existent, the pump would be sucking air.

 

[NYCruiser]

Oh, and just because nobody's been a ******* yet……..

Maybe its just the Chevy rejecting the donor organ?……..J/K

 

[Greg36]

We pulled the pan off yesterday and yes the o ring had a spot that looked bad, but we replaced it thinking that would resolve the problem, didn't do a thing. Yes we had to modify the pickup tube, but only had to shave off about 1/2" to get the pan to seat correctly. This pan holds more oil than stock looking like around 8 quarts. Will try to get photo of pan, its a real pain in the a$$ to get pan off, basically pull headers/steering linkage/stabilizer/motor mounts/jack up motor/ etc. etc. etc. if you get what I am saying. Yeah maybe this chevy just wants a boring old 350 in it!lol

 

[Greg36]

Heres a photo of the oil pan for the hemi/chevy bel air.

 

[NYCruiser]

So, the linkage path is a full baffle inside the pan? Can oil pass under the linkage to fill the section with the oil pickup? How full of oil is that pan? Are you sure the oil fill line is higher than the linkage baffle? I'm thinking the pump is sucking half the pan dry and not refilling fast enough.

I'd have to suspect that pan design. You may want to consider a dry sump application here.

 

[Redtruck-VA]

Ahh a bread box, reminds me of some of the pans we used on our chevy II's back in the day. Is the pick-up tube flexible ie possibly collapsing. Where is the actual pickup located in the pan? As stated any small leak will prevent oil from being picked up. Maybe an external oil return bolted to the outside of the pan? I'm thinking simply a air leak on the modified pickup.