Oil Pressure Issue?

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DartVadar

DartVadar

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I know this is asked a lot, and a lot are probably going to say everything is fine, but I still feel like it should be higher.

The motor is a 360, rebuilt last year, stock crank and rods with ARP rod bolts, KB pistons etc. Has a Lunati solid roller, 245 @50 and 580 lift with MRL lifters. Edelbrock heads and comp ultra pro magnum roller rocker arms. Bearing clearance are 2.5 thou on the mains and rods If I remember correctly.

The motor has about 5-6k miles on it and its been running really good, no problems. Oil pressure hasn't changed from when I first started it either.

Cold start is is about 70 psi, and when it warms up it goes down to about 25 PSI at idle in gear at about 850. Cruising its about 60 above 2000rpm and never really goes above that. What gets me is this is with 20w-50 oil, I would expect to be making a lot more pressure. I can't imagine how much lower it would be with 30 weight or something.

The oil pump was brand new when I put it in and is a melling HV pump. The lifters are pressure oiled, so that bleeds off some pressure, but the rocker arms get stupid amounts of oil, they absolutely flood the tip and pushrod cup, could this be bleeding a lot of pressure?

Should I just leave it as is? or is it time to troubleshoot? I haven't tried a different gauge, so it could also simply be an inaccurate mechanical gauge.
 
That sounds like alot of pressure drop from cold to warm. I usually see 10 - 15 psi loss when the engine warms up.

You may want to look more closely at the rocker arm "get stupid amounts" of pressure.
 
DartVadar said:
I know this is asked a lot, and a lot are probably going to say everything is fine, but I still feel like it should be higher.

The motor is a 360, rebuilt last year, stock crank and rods with ARP rod bolts, KB pistons etc. Has a Lunati solid roller, 245 @50 and 580 lift with MRL lifters. Edelbrock heads and comp ultra pro magnum roller rocker arms. Bearing clearance are 2.5 thou on the mains and rods If I remember correctly.

The motor has about 5-6k miles on it and its been running really good, no problems. Oil pressure hasn't changed from when I first started it either.

Cold start is is about 70 psi, and when it warms up it goes down to about 25 PSI at idle in gear at about 850. Cruising its about 60 above 2000rpm and never really goes above that. What gets me is this is with 20w-50 oil, I would expect to be making a lot more pressure. I can't imagine how much lower it would be with 30 weight or something.

The oil pump was brand new when I put it in and is a melling HV pump. The lifters are pressure oiled, so that bleeds off some pressure, but the rocker arms get stupid amounts of oil, they absolutely flood the tip and pushrod cup, could this be bleeding a lot of pressure?

Should I just leave it as is? or is it time to troubleshoot? I haven't tried a different gauge, so it could also simply be an inaccurate mechanical gauge.
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So you are saying its pushrod oiling? If so, I would try to get the oil going up under control.
 
Thats what I was thinking too. Well it usually idles at 1000, but goes down a bit in gear. So at 1000 its about 35 PSI.

It oils through the heads and then the shaft. The rockers oil the tip and the pushrod cup. its not a trickle, they are flooded lol

Would restrictors up top help?
 
20/50 oil is 20 weight. 30 is 30 weight. 10/30 is 10 weight. If you only drive in warm weather and it a solid lift. put 50 weight race oil in it.
 
Nothing wrong with that Oil Pressure! Just leave it alone. That is one of the reasons Car Companies stopped putting in oil pressure gauges. Owners would get scared of "what ever the oil pressure was" No matter WHAT it was!
 
Mopar Tim said:
Nothing wrong with that Oil Pressure! Just leave it alone. That is one of the reasons Car Companies stopped putting in oil pressure gauges. Owners would get scared of "what ever the oil pressure was" No matter WHAT it was!
Click to expand...

Exactly!!!!!!!!!!! There is no problem here. Leave it alone.
 
Oldmanmopar said:
20/50 oil is 20 weight. 30 is 30 weight. 10/30 is 10 weight. If you only drive in warm weather and it a solid lift. put 50 weight race oil in it.
Click to expand...

You are wrong. The base stock starts as the winter grade number but the viscosity index improvers work with temperature to increase viscosity.

Single grade oils were rendered USELESS after WWII.
 
DartVadar said:
Thats what I was thinking too. Well it usually idles at 1000, but goes down a bit in gear. So at 1000 its about 35 PSI.

It oils through the heads and then the shaft. The rockers oil the tip and the pushrod cup. its not a trickle, they are flooded lol

Would restrictors up top help?
Click to expand...

I would not restrict the oil if it's NOT PR oiling. If it's factory Chrysler like you say, it is self adjusting...backwards.

As RPM goes up, oil to the shafts goes down.

If oil is backing up in the heads you need to address drain back issues, unless someone made it so you get full time oil to the heads, like a wide, deep, groove in the cam around the number 2 and 4 cam bearings. I only do that over 7500 RPM or so, depending on application.

Whose rockers and shafts?

EDIT: I see they are comp rockers. Haven't seen any in a while. Do they have two bushings in each rocker with a gap in the middle? If so, that lets oil to the rocker full time. I think it's stupid. I may be dealing with it on some PRW rockers I am using. If I have too much oil, the rockers will go to Rocker Arm Specialists for a full width bushing and I will drill the correct oil holes in the bushing and shaft.

The Chrysler system is fool proof if you understand it. If you don't, you do stupid things like split bushings.
 
yellow rose said:
You are wrong. The base stock starts as the winter grade number but the viscosity index improvers work with temperature to increase viscosity.

Single grade oils were rendered USELESS after WWII.
Click to expand...

Well......sorta. The first number is the weight before the oil reaches operating temperature. Once there, it is the second number.

I have assumed for years that the "W" stood for winter, but it does not. At least from what I can dig up on the net. The best that I can find is that it means "when cold" or before operating temperature.

At least, that's what I have gathered from most of the oil sites.

So basically, if you have 20/50, it is essentially 50 weight because that's what it is when warmed up.

At least, this is what I have inferred from reading. I could be slam wrong.
 
RustyRatRod said:
Well......sorta. The first number is the weight before the oil reaches operating temperature. Once there, it is the second number.

I have assumed for years that the "W" stood for winter, but it does not. At least from what I can dig up on the net. The best that I can find is that it means "when cold" or before operating temperature.

At least, that's what I have gathered from most of the oil sites.

So basically, if you have 20/50, it is essentially 50 weight because that's what it is when warmed up.

At least, this is what I have inferred from reading. I could be slam wrong.
Click to expand...

No you are close. The W actually does stand for Winter. The issue is all the WINTER grades are measured at different temperatures. And, just to make it difficult, API does NOT recognize winter grades above 25.

Let's take a 20 winter grade oil. Off the top of my head, IIRC, it acts like a 20 at 32* or colder. A 15 winter grade is measured at 20*. A 5 winter grade is down at ZERO again if IIRC correctly, but I am close.

One of the reasons I spend big money per quart of oil is I can run a 5w50 and not have an issue if I show up at the track and its 40*'s in the early morning, and where I live, it can be. Then you get a 50 when its hot. For my street stuff, I can use a 5w30 and drive it year round.

I'm old enough (probably RRR is too) to remember Castrol had a 10w50 way back in the day. It was a good oil, but due to the fact it was a mineral oil, it was very expensive to have that much spread between the winter grade number and the running temp number, so it was dropped. That was about the time I switched to synthetics so no bones for me. But other guys were pissed.
 
Yeah that makes sense. I knew the part about when the oil was hot it was the second number, but the rest was kinda fuzzy. lol

And I remember sellin 10/50 in the local speed shop when I was a kid. Funny you brought that up. I think I remember Valvoline made it too.
 
RustyRatRod said:
Well......sorta. The first number is the weight before the oil reaches operating temperature. Once there, it is the second number.

I have assumed for years that the "W" stood for winter, but it does not. At least from what I can dig up on the net. The best that I can find is that it means "when cold" or before operating temperature.

At least, that's what I have gathered from most of the oil sites.

So basically, if you have 20/50, it is essentially 50 weight because that's what it is when warmed up.

At least, this is what I have inferred from reading. I could be slam wrong.
Click to expand...

No. This is correct. I'm up in canada and we have to pay close attention to how the oil viscosity works.

Not to repeat RRR. But the number before the W is its rating when cold. After the W is at that oil's operating temperature. Note though that different oils have different operating temps.

EX: 5W30
5 When cold
30 When at operating temp

The W thing is just an old hang around because it was designed to work in winter and summer. So guys used to call it 5 WINTER then whatever summer oil. Which is a misnomer in itself. Oil is considered cold whenever it isn't in its operating temperature range. Even if its 30+ (Celsius) out. It's technically still "cold" oil in the pan. It just warms up faster than when it's -30 out.
 
RustyRatRod said:
Yeah that makes sense. I knew the part about when the oil was hot it was the second number, but the rest was kinda fuzzy. lol

And I remember sellin 10/50 in the local speed shop when I was a kid. Funny you brought that up. I think I remember Valvoline made it too.
Click to expand...



Valvoline had it too. Like I said, price point killed it. Pretty difficult to get a spread that far from winter grade to running grade.

Luck for us, WWII produced some very cool tech, especially in lubrication (and hundreds of other technologies) that would have come along decades later, if not for the war. Was the war worth it? IDK, I'd leave that up to the MIC and the king makers to determine that.
 
Lustle said:
No. This is correct. I'm up in canada and we have to pay close attention to how the oil viscosity works.

Not to repeat RRR. But the number before the W is its rating when cold. After the W is at that oil's operating temperature. Note though that different oils have different operating temps.

EX: 5W30
5 When cold
30 When at operating temp

The W thing is just an old hang around because it was designed to work in winter and summer. So guys used to call it 5 WINTER then whatever summer oil. Which is a misnomer in itself. Oil is considered cold whenever it isn't in its operating temperature range. Even if its 30+ (Celsius) out. It's technically still "cold" oil in the pan. It just warms up faster than when it's -30 out.
Click to expand...

Nope, it's winter grade. When I get home, I will look up and post all the winter grade temps, and how wide the grade spreads really are, so the correct info is out there.
 
So does that mean everything with the "W" in the middle of two oil grades is winter blend? Because that's on store shelves year round.
 
RustyRatRod said:
So does that mean everything with the "W" in the middle of two oil grades is winter blend? Because that's on store shelves year round.
Click to expand...

I gotta throw in on this. I was taught that the first # is what it flows like on start up, and the second # is the protection you have after it`s warmed up. phillups 66 used to make a 20w40, I ran it in my 68 form-383-form S fastback when it was new. really liked that oil! don`t know when they dropped it.
 
famous bob said:
I gotta throw in on this. I was taught that the first # is what it flows like on start up, and the second # is the protection you have after it`s warmed up. phillups 66 used to make a 20w40, I ran it in my 68 form-383-form S fastback when it was new. really liked that oil! don`t know when they dropped it.
Click to expand...

Yes. That is my understanding as well.
 
Gettink back to the OP
What if you have dual oiling of the top end; that is through the regular passages to the rocker shafts, and up the pushrods. That would put "stupid oil up top".

I had the opposite problem with my LA 360 and Melling HV pump. I had stupid hi-pressure that would blow the filter pad off the block and dump oil onto the header.That's not good.So I made some mods,switched to 10W30, and Good to go.
 
We caint have no stupid oil.
 
yellow rose said:
I would not restrict the oil if it's NOT PR oiling. If it's factory Chrysler like you say, it is self adjusting...backwards.

As RPM goes up, oil to the shafts goes down.

If oil is backing up in the heads you need to address drain back issues, unless someone made it so you get full time oil to the heads, like a wide, deep, groove in the cam around the number 2 and 4 cam bearings. I only do that over 7500 RPM or so, depending on application.

Whose rockers and shafts?

EDIT: I see they are comp rockers. Haven't seen any in a while. Do they have two bushings in each rocker with a gap in the middle? If so, that lets oil to the rocker full time. I think it's stupid. I may be dealing with it on some PRW rockers I am using. If I have too much oil, the rockers will go to Rocker Arm Specialists for a full width bushing and I will drill the correct oil holes in the bushing and shaft.

The Chrysler system is fool proof if you understand it. If you don't, you do stupid things like split bushings.
Click to expand...

Yeah they have two bushings with a big space in between them. So could this be having an impact on oil pressure then?
 
AJ/FormS said:
Gettink back to the OP
What if you have dual oiling of the top end; that is through the regular passages to the rocker shafts, and up the pushrods. That would put "stupid oil up top".

I had the opposite problem with my LA 360 and Melling HV pump. I had stupid hi-pressure that would blow the filter pad off the block and dump oil onto the header.That's not good.So I made some mods,switched to 10W30, and Good to go.
Click to expand...

I actually didn't think about that. I dont think so, I believe that my pushrods are solid. They are custom smithbrothers pushrods. I know the rocker arms have a hole in the pushrod cup that would send oil to the rockers. I'll have to look into that.

When I was priming the motor before installing it, the pushrods would be so flooded with oil they would have about a 1/4 of oil thickness going down along them. The springs were flooded with oil too. The oil would make the spring look solid if that makes sense. I mean everything is definitely getting oil up top! lol
 
DartVadar said:
I actually didn't think about that. I dont think so, I believe that my pushrods are solid. They are custom smithbrothers pushrods. I know the rocker arms have a hole in the pushrod cup that would send oil to the rockers. I'll have to look into that.

When I was priming the motor before installing it, the pushrods would be so flooded with oil they would have about a 1/4 of oil thickness going down along them. The springs were flooded with oil too. The oil would make the spring look solid if that makes sense. I mean everything is definitely getting oil up top! lol
Click to expand...

If that is what you have, there is no way to stop oil to the top. Chrysler did it so the only oil the pushrod gets is when the hole in the shaft lined up with the hole in the rocker arm. That was while the valve was shut.

Some super engineer decided to make it so the pushrod gets oil all the time. I actually called PRW and tried to get an understanding of why they do what they do. I suspect comp would be no different.

I will be hot if I have to send my rockers out to be rebushed just to correct an oil problem that they said would not be an issue.
 
I think your pressure is nothing to worry about. I would double check if the rockers are a split bushing and if the pushrods are oil thru. U want non oil thru pushrods.
 
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