Breaking in engine... oil press seems low...

[Crammysauce!]

Hello again - so I am finally running my engine to break in the cam, and after about ten minutes of running, the oil pressure was staying at around 17-18 psi. This is at 2000 rpm. Is this low, or am I just overreacting? What are some oil pressure psi numbers I should look for under normal operating conditions? Idle, driving, WOT, etc. Thanks!!

 

[cabech984]

Did you rebuild the oil pump too? Or was the oil psi good on the old one? My new engine shows 40 psi on startup idle, and 20 psi @ hot idle. Rule of thumb is 10 psi for every 1000 rpms.

 

[Crammysauce!]

Yeah, I got one of the high volume units with a new front cover from white racing. Is this low, or okay? It went from around 75-80 psi at startup to 17-18 at 2000 rpm warmed up. Any ideas?

 

[mikestertwo]

That pressure seems kind of low even for a stock pump. Sounds like you have too much clearance somewhere, pump or bearings, or a cam bearing not installed correctly.

 

[Evans Ward]

What clearances did you or your engine builder set the oil pump gears at end and side play? TA Performance have a neat shim kit which is a variety of gasket thicknesses that helps out nicely. Was the pump primed prior to initial start up?

 

[BlackBandit]

That pressure seems kind of low even for a stock pump. Sounds like you have too much clearance somewhere, pump or bearings, or a cam bearing not installed correctly.

I agree, that's way to low for 2000 rpm.

 

[Crammysauce!]

I primed the pump. Maybe I need to try out that shim kit. I really couldn't see the parts being the problem. It sounds more like a clearance issue. ALL of the parts are brand new.

My engine builder just got the shortblock together for me, so the oil pressure deal is my own fault I'm sure. I'll just have to experiment, I guess. Nothing new there.

Could someone post some normal operating pressures under different conditions, please. I first need to know what values I'm looking for. Thanks again, guys!

 

[Jerryl]

I primed the pump. Maybe I need to try out that shim kit. I really couldn't see the parts being the problem. It sounds more like a clearance issue. ALL of the parts are brand new.

My engine builder just got the shortblock together for me, so the oil pressure deal is my own fault I'm sure. I'll just have to experiment, I guess. Nothing new there.

Could someone post some normal operating pressures under different conditions, please. I first need to know what values I'm looking for. Thanks again, guys!

By now you already know the oil pressure is way low. :frown:
At cold start-up (80 deg weather) with 10-30, I see around 70 psi.
Hot idle (165F coolant temp) around 22 psi. (825 rpm)

Personaly, I'd quit running it untill you get it sorted out.
Pull the oil pump cover and make sure and/or set the clearances to 0.001 - 0.0015 - Use some plastigage. Make sure the cover is flat and not scored.
If that does not resolve the problem, it is time to go back through the motor b4 something BAD happens.

 

[cabech984]

Did you rebuild the oil pump too? Or was the oil psi good on the old one? My new engine shows 40 psi on startup idle, and 20 psi @ hot idle. Rule of thumb is 10 psi for every 1000 rpms.

This is w/ the 40psi spring. Id re-do the pump as well if I was you

 

[Crammysauce!]

I'm definitely done running the motor until I get it worked out. I will have to check the clearances and see about getting some new pump internals if they check good. I wonder if anyone else has had a similar condition, and what the fix was... thanks again!

 

[mikestertwo]

Is the new front cover you are using a GM cover or one of those high volume aftermarket covers? I have had a lot of problems with the aftermarket covers. That's why I don't use them. I have had covers with anything from the gears being off center in the bores to the bore for the pressure regulator being way too large or oval shaped.

 

[cabech984]

I'm definitely done running the motor until I get it worked out. I will have to check the clearances and see about getting some new pump internals if they check good. I wonder if anyone else has had a similar condition, and what the fix was... thanks again!

Any idea what the oil pressure is @ idle(cold & hot idle)

 

[Brer Rabbit]

oil pressure #s.

I have a hi-volume pump, and at startup I have upper 70psi with 10-30, and after a while it will go down to about 35-38 in gear at a traffic light. There is a restrictor fitting on my 67dual ball bearing turbo that may have something to do with that psi numbers and also the huge filter on the turbo saver may also contribute. I am not running an oil cooler at this time either. Hope that helps.

 

[gsbuick65]

ok my readings are-foot on brake in gear=12 psi, hwy. @ 65 mph 56 psi. new dorman cover but i got .002 clearance between gears and cover. thats with a 60psi spring. motor hot.

 

[BlackBandit]

I have a high volume cover/pump I did the earls mods to along with some bearing mods. With fairly loose clearances in the engine I get 25 psi hot at idle, 20 in gear at idle and it jumps almost instantly to 60 when I hit the gas. The only time it gets higher than that is when I'm hard on the gas. I'm going to switch to a 5w-20 and see what I get but I think it's going to be similar. Just to clarify, "hot at idle" is after I've been driving it and I don't have a oil cooler yet. HTH. james

 

[cabech984]

I have a high volume cover/pump I did the earls mods to along with some bearing mods. With fairly loose clearances in the engine I get 25 psi hot at idle, 20 in gear at idle and it jumps almost instantly to 60 when I hit the gas. The only time it gets higher than that is when I'm hard on the gas. I'm going to switch to a 5w-20 and see what I get but I think it's going to be similar. Just to clarify, "hot at idle" is after I've been driving it and I don't have a oil cooler yet. HTH. james

Why switch to 5w-20? I thought 20 psi @ hot idle was acceptable? Well, maybe not for a HV pump??

 

[BlackBandit]

Because the jump over the set pressure at higher rpms means I have thicker oil than I need to maintain my desired pressure. If I use a lighter oil I'll still have enough oil pressure, I'll just have more flow which will cool the bearings better. FWIW I'm not too worried about oil pressure at idle. As long as it's there and it comes up immediately when the rpms come up it's good because there's no load at idle.

 

[GARY HARVEY]

Rotella/Racing oil

I hope you are using Rotella or some other RACING oil and at a mimimum
GMs oil additive.

 

[Crammysauce!]

Thanks for all of the replies, guys. I think I have a part lined up that should be able to fix this. It's the adjustable oil pressure regulator from TA Performance. I'll be contacting them Monday. I will try it out anyway, and let you know how it works out. If it doesn't work, at least I'll have another measure of adjustability on the car.

 

[Mark E.]

Just a thought, but are you sure the plugs are in the oil galleys behind the timing chain gear? Sounds like you are hemmoraging.