do mopars just get low oil psi or is it just mine?

Posted By: coronet1966d

do mopars just get low oil psi or is it just mine? - 04/16/10 05:51 PM

the 360 i pulled out would idle at about 12psi hot with 20w50

now my fresh 440 with a high volume pump gets about 8psi hot idle with brad penn 10w30

the engine is all new and assembled by a machine shop, clevite bearings melling high volume pump ect. on cold startup its at about 75psi. then it gradually drops as it warms up. the oil pressure is responsive as it should be to engine RPM. when hot it goes up to 50psi at most

any ideas?

Posted By: stumpy

Re: do mopars just get low oil psi or is it just mine? - 04/16/10 06:04 PM

What oil gauge, what temp and what idle speed?

Posted By: radar

Re: do mopars just get low oil psi or is it just mine? - 04/16/10 06:07 PM

My fresh build (small block) had a high volume pump. I seized it with a small piece of trash that got sucked in. I replaced it with a melling standard flow. My gauge still reads 10-15 at idle (900 rpm) and stays at or above 10psi per 1000rpm.

Gotta be loose bearing clearances? I also run the purple 10w30 synthetic.

Posted By: MoparforLife

Re: do mopars just get low oil psi or is it just mine? - 04/16/10 06:17 PM

I have nothing that has that low of pressure even with many thousands of miles on them.

Posted By: therocks

Re: do mopars just get low oil psi or is it just mine? - 04/16/10 06:21 PM

My old 318 had 280K and at idle hot had like 10 psi.Ran for 4 years till I sold it and was running good after at least 3 more years that I know of.My 440 hi press hi vol pump has 80 cold and never drops below 65.My kis 62 413 carries 60 cold and minimum 45 hot.Rocky

Posted By: coronet1966d

Re: do mopars just get low oil psi or is it just mine? - 04/16/10 07:32 PM

Quote:

What oil gauge, what temp and what idle speed?

its an autometer short sweep electric 0-100psi

temp at idle is about 150 but it gets as high as 180

idle speed is about 1000

Posted By: coronet1966d

Re: do mopars just get low oil psi or is it just mine? - 04/16/10 07:36 PM

Quote:

My fresh build (small block) had a high volume pump. I seized it with a small piece of trash that got sucked in. I replaced it with a melling standard flow. My gauge still reads 10-15 at idle (900 rpm) and stays at or above 10psi per 1000rpm.

Gotta be loose bearing clearances? I also run the purple 10w30 synthetic.

yours sounds exactly like mine. (minus the seized oil pump part) this is a tight fresh engine with no more than 40 miles on it. a machineist did the lower end i assembled the rest

Posted By: dOc !

Re: do mopars just get low oil psi or is it just mine? - 04/16/10 07:40 PM

Corny ... it sound like you have a L O S S E L Y clearanced motor.

Posted By: 5spdcuda

Re: do mopars just get low oil psi or is it just mine? - 04/16/10 08:09 PM

Clearances are probably on the loose side. Also high volume isn't the same as high pressure. I use a high pressure spring in any modified engine. With 20-50 weight oil my cold pressure is 75-80 psi. Hot idle is 40 psi, 30 psi if it's been run hard. Hot pressure at 2000 rpm is 60-65 psi. Pressure is 5 psi lower when using thinner oils. Most stock Mopars run 45-50 psi at 2000 rpm hot and anything from 15-30 psi at hot idle.

Posted By: Slipknot440

Re: do mopars just get low oil psi or is it just mine? - 04/16/10 08:17 PM

my hemi idles at 900 rmps and 60psi in park, 15-20 psi in drive on the brake and drives around 50 at 1500-3000 rpms

Posted By: stumpy

Re: do mopars just get low oil psi or is it just mine? - 04/16/10 08:55 PM

You need to get that engine temp up to a least 190* for the engine to be at it's best.

Posted By: JoesMopar

Re: do mopars just get low oil psi or is it just mine? - 04/16/10 09:05 PM

My:

440 in '69 Charger - 70psi @ cold idle, 50psi warm idle and cruising... GTX 20W-50
318 in '89 Diplomat - 55psi @ cold idle, 50psi crusing warmed up, 25 psi warm idle... Napa 10W-30
318 in '68 Satellite - 70psi @ cold idle, 60 psi crusing and warm idle... Napa 10W-30

Posted By: RapidRobert

Re: do mopars just get low oil psi or is it just mine? - 04/16/10 09:05 PM

Quote:

now my fresh 440 with a high volume pump gets about 8psi hot idle with brad penn 10w30.
the oil pressure is responsive as it should be to engine RPM. any ideas?

go w the next thicker grade. Actually if it jumps up immediately when you gun it you are Ok though 8 is getting close to the ragged edge. I'd think loose clearances also, somewhere

Posted By: Challenger 1

Re: do mopars just get low oil psi or is it just mine? - 04/16/10 09:12 PM

Quote:

Quote:

now my fresh 440 with a high volume pump gets about 8psi hot idle with brad penn 10w30.
the oil pressure is responsive as it should be to engine RPM. any ideas?

go w the next thicker grade. Actually if it jumps up immediately when you gun it you are Ok though 8 is getting close to the ragged edge. I'd think loose clearances also, somewhere

I have a 1981 International truck with a 345 ci gas engine in it. When it idles it has 1-2 lbs oil pressure when hot. when you gas it it jumps up. Been that way since I bought the truck 15 years ago. It's a old utility truck with a crane mounted on it. I suspect it idled all day long when it was in service for the utility company. Anyway it won't die, it just keeps on running sometimes for hours at a time for us with the dash gauge showing 0.

Anyway to the OP, That sounds too low for a new engine. I'm thinking some bearings got wiped during start up? Sorry not good.

Might want to cut a oil filter apart to rule out what I'm saying.

Posted By: Hoof Hearted

Re: do mopars just get low oil psi or is it just mine? - 04/16/10 09:42 PM

Quote:

Corny ... it sound like you have a L O S S E L Y clearanced motor.

I'm guessing he meant L O O S E L Y

but I agree.

Posted By: coronet1966d

Re: do mopars just get low oil psi or is it just mine? - 04/16/10 09:46 PM

Quote:

Clearances are probably on the loose side. Also high volume isn't the same as high pressure. I use a high pressure spring in any modified engine. With 20-50 weight oil my cold pressure is 75-80 psi. Hot idle is 40 psi, 30 psi if it's been run hard. Hot pressure at 2000 rpm is 60-65 psi. Pressure is 5 psi lower when using thinner oils. Most stock Mopars run 45-50 psi at 2000 rpm hot and anything from 15-30 psi at hot idle.

where can i get a high pressure spring?

Posted By: 5spdcuda

Re: do mopars just get low oil psi or is it just mine? - 04/16/10 09:53 PM

M P has them so any Chrysler dealer or M P dealer such as Mancini, Hensley, Muscle Motors etc. Costs about $5.00.

Posted By: coronet1966d

Re: do mopars just get low oil psi or is it just mine? - 04/16/10 09:58 PM

i guess ill try that before heading over to the machineists house with torches

Posted By: dOc !

Re: do mopars just get low oil psi or is it just mine? - 04/17/10 01:03 AM

Quote:

Quote:

Corny ... it sound like you have a L O S S E L Y clearanced motor.

I'm guessing he meant L O O S E L Y

but I agree.

Oooooops !

...and me thimks your machinist needs to go back to FIRST GRADE !

Posted By: scratchnfotraction

Re: do mopars just get low oil psi or is it just mine? - 04/17/10 01:19 AM

I beg to differ here

electric guages just show its working some and IMO are not a reliable as a mech guage

I had the same thing till I went back to the mech autometer gauge

i say put a mech on and check it first before working on something thats not broke

my sb 318 holds 25 hot idle in gear at 850rpms 75 at 2500rpms almost 250,000 miles on it

my BB used engine 75,000 miles was low pessure on elect gauge and flickerd the stock oil light in the dash

swaped to the mech gauge

now its up around 70 hot and 30 at hot idle

sender was going bad maybe,it would be at 30lbs on mech gauge and flicking the oil light on the elect gauge compairing the 2 at the same time

cant believe all you have in that 440 and its on the loose side

did you do any oil mods? full groove bearings?

did you get your seal fixed?

how was the lifter bores?? in spec on the bore size?

IMO,I would double check with mech gauge first move to see if the gauge is correct

result will vary by gauge,IMHO

Posted By: DaytonaTurbo

Re: do mopars just get low oil psi or is it just mine? - 04/17/10 07:06 AM

Quote:

Clearances are probably on the loose side. Also high volume isn't the same as high pressure. I use a high pressure spring in any modified engine. With 20-50 weight oil my cold pressure is 75-80 psi. Hot idle is 40 psi, 30 psi if it's been run hard. Hot pressure at 2000 rpm is 60-65 psi. Pressure is 5 psi lower when using thinner oils. Most stock Mopars run 45-50 psi at 2000 rpm hot and anything from 15-30 psi at hot idle.

My tired stock bearing/crank 440 ran 75-80psi cold with 15 or so at a 700rpm idle in gear. Any amount of throttle and the oil pressure would shoot right up, and that's with an original pump/spring pushing 10w-30 oil. Your HP spring and thicker oil doesn't seem to develop any more pressure than my tired stocker did. I later tried putting in a HV pump, and saw a small increase in pressure at idle, 5psi or so, with the biggest difference being it built a lot more pressure quickly with any amount of throttle.

You can't have pressure without volume. A high pressure relief spring will do nothing for the OP. All a high pressure spring does is raise the upper limit of oil pressure you will develop before the relief pops, and trust me, the relief is a hell of a lot higher than 8psi. What you need is more volume, and if you're already running the HV pump, about the only thing you can try is a thicker oil.

You can try the stiffer spring if you want, however I would bet it will gain you nothing.

Posted By: Supercuda

Re: do mopars just get low oil psi or is it just mine? - 04/17/10 12:36 PM

Quote:

where can i get a high pressure spring?

Won't help you.

The high pressure spring sets the MAXIMUM oil pressure. It will not raise you lower oil pressure at idle.

The only caveat is if the pressure relief valve is sticky, taking it apart to install a new spring might loosen it up and get it working. But it won't be the spring that fixed it. There was a batch of oil pumps a few years back that had this problem and I think it was Melling pumps too.

Posted By: NITROUSN

Re: do mopars just get low oil psi or is it just mine? - 04/17/10 01:36 PM

Quote:

its an autometer short sweep electric 0-100psi

Better check it properly with a known properly calibrated mechanical guage. Thats the FIRST thing you need to do.

Posted By: bobby66

Re: do mopars just get low oil psi or is it just mine? - 04/17/10 03:24 PM

Fully grooved main bearings? Some are wider than others and if you have clearances on the loose side with wide groove mains that could contribute to your situation.

Posted By: Pacnorthcuda

Re: do mopars just get low oil psi or is it just mine? - 04/17/10 03:33 PM

Quote:

Quote:

where can i get a high pressure spring?

Won't help you.

The high pressure spring sets the MAXIMUM oil pressure. It will not raise you lower oil pressure at idle.

The only caveat is if the pressure relief valve is sticky, taking it apart to install a new spring might loosen it up and get it working. But it won't be the spring that fixed it. There was a batch of oil pumps a few years back that had this problem and I think it was Melling pumps too.

Exactly. A High pressure spring aint gonna help one iota. Its only goning to keep the relief valve from opening until a higher pressure is reached at speed. At lower pressures the regular spring is keep the valve closed just fine.

The pump itself could have excessive clearannce between the rotor and the case. Considering the low cost and ease of replacement on a BB you might want to try a different HV pump, or machine down the case clearance on this one.
But in all probability it is a loose motor. You could drop the pan and plastigage the bearing clearances...