Lower oil pressure with SBC Rockers on 3x00?

[91BerettaGT]

I just finished my install of the Crane Cams 1.6:1 Gold race Roller rockers...

I also installed hte LS1 Valve springs, with the Chrysler Valve stem seals and the LS1 Valve spring seats or shims if you prefer (grinded out in the middle)

I had a few problems adjusting them and actually i need to adjust them 1 more time ...

Anyway my first problem is that I was doing the lower intake gasket. I am more than positive that when i did the Oil pump drive (distributor cover) that I inserted it in the proper location. As i remember, it was a HEX drive oil pump shaft. Impossible to insert improperly. ...

Anyway i got it running and adjusted them running. No tapping. I also flushed my oil (used same type oil as before., Mobil 1 Synthetic Oil with the K&N OIl filter, Same stuff i've always used since the beginning).

Now when i come to a light at idle, I come really close to 0 psi oil pressure. Warm. obviously.

Before the rockers were installed, warm at idle would be 20psi.

Maybe it's just the weather here but that is low right? The sender is new, cluster is new so i know it's not failed.

Is there a way I can measure resistence value's on the sender to get a real true reading?. I'm tempted to plug into the 3x00's spot for a light on/light off gauge reading (light on would be gauge pinned down, light off pinned up)

Is it possible that these new rockers flow really well? Well enough to drop my oil pressure readings below my likings? The gauge does increase whne you revv.

3000 rpms cold is around 60psi.
Idle cold is around 10psi

Now i am reading my stock gauge of couse, nothing aftermarket. I'm simply estimating, being bottom is 0, top is 80.

AHH these rockers are driving me crazy!

[geoffinbc]

Not the rockers man. Had them on several vehicles. Did you install a new oil pump drive seal?

[91BerettaGT]

Not the rockers man. Had them on several vehicles. Did you install a new oil pump drive seal?

Now that I think about it I just added the oil pump drive shaft gasket. There wasn't one there in the first place and it was leaking oil out of it. The tech's at the Dealership gave me 2 O rings, and 1 O gasket for the distributor, they said for the distributor cover add a little bit of Gasket maker, (they gave me GM's Assembly sealent and Blue locktite)

Should I take that out? I physically did not remove the oil pump. Just the drive shaft on the top (distributor cover)

Could the gasket be acting as a shim and preventing movement of the oil pump drive shaft? making less oil pressure at idle?

[Doubt_Incarnate]

if you had the motor completely apart and did the main bearings, the reamost bearing cap has a spot drilled out arond the pump shaft for an o-ring. if thats not there you can have low pressure

[geoffinbc]

There is on O-Ring on the oil pump driveshaft too. That needs to be there.

[91BerettaGT]

There is on O-Ring on the oil pump driveshaft too. That needs to be there.

Ah thats right, they did also give me an o ring for that too... I did install it,

I'm still lost as to why i have low pressure

if you had the motor completely apart and did the main bearings, the reamost bearing cap has a spot drilled out arond the pump shaft for an o-ring. if thats not there you can have low pressure

I never took the block apart, Just did the LOWER intake manifold. Thats all. NO BEARINGS.

[geoffinbc]

Do anything to the lifters? Even if there was no pushrods in the valvetrain there would be no drop in pressure. Oil is limited to the upper end of the block by the size of the oil hole in the lifter. In addition to that the block is priority main feed so oil is always pressurized at the mains and lifter galley at the same time. I am wondering did the o-ring on the drive shaft fit tight to the hole in the block?

[RednBlack]

My first move would be to use a manual oil pressure gauge. Isolate a few things out. Just my opinion..

[91BerettaGT]

Do anything to the lifters? Even if there was no pushrods in the valvetrain there would be no drop in pressure. Oil is limited to the upper end of the block by the size of the oil hole in the lifter. In addition to that the block is priority main feed so oil is always pressurized at the mains and lifter galley at the same time. I am wondering did the o-ring on the drive shaft fit tight to the hole in the block?

Yes, it did it was quite a struggle to get it to wiggle in.

I remember adjusting the rockers, only the rockers at the ends of the block SHOT oil out, the other's just kinda dribbled.

Think my lifter's are shot? Take in mind the engine now has 25471 miles on it. Fairly new. I did bend 1 pushrod, is it possible i hurt that lifter enough to give me a bad reading?

As for the mechanical gauge i'm going to soon... waiting on funds. I don't want to drive it with that little oil pressure.

I called crane cams, they said each rocker should be SHOOTING out oil. well 4 out of 6 on the front, and just about all 6 in the back are not shotting but more so dribbling. What should I do, i really don't feel like tearing it apart again but i need it on the road so whatever is necessary ya know?

[geoffinbc]

I dont know if this applies to the GenIII. But some roller lifters need to be installed with the oil holes towards the cam. Usually this is not the case. I have not seen a GM engine where this is true. Lifters will not cause low oil pressure in the engine unless they are missing or the the oil grooves are so big they are allowing too much oil to pass by lowering the pressure. Furthermore oil will usually only squirt out of the pushrod at about 2000+RPM or so.

[91BerettaGT]

Here's everything I did.

Bent 1 pushrod, installed a new one.

LS1 Valve springs.
LS1 Valve shims
Chrysler valve stem seals
3400 Retainer
3400 locks

Changed studds to the ones included in the crane cams kit.
Using Crane Cams Gold Race 1.6:1 Roller rockers and I Gasket Matched the Intake side of the heads and intake manifolds and the plenum.

Changed the O ring on the Oil pump drive. Added the Oil PUmp drive O ring seal.

Changed intake gasket.

Flushed oil after everything was done so that the oil shavings were not in my oil pan waiting to be sucked up by the oil pump.

Then reassembled everything

I dont know if this applies to the GenIII. But some roller lifters need to be installed with the oil holes towards the cam. Usually this is not the case. I have not seen a GM engine where this is true. Lifters will not cause low oil pressure in the engine unless they are missing or the the oil grooves are so big they are allowing too much oil to pass by lowering the pressure. Furthermore oil will usually only squirt out of the pushrod at about 2000+RPM or so.

When i revv to a solid 2000 rpms. I get 40psi. on the gauge. 60 at 3000 rpms.

I was told 10psi for every 1000 rpms is REQUIRED MINIMUM.

Has anyone else who did this use synthetic? Maybe it's just because it's a hott day?

I know that synthetic will normally give a lower oil pressure reading because it uses smaller particals. My co-worker said that he ran synthetic once in his big block, he didn't like how oil pressure was so low. he had a nice truck

[geoffinbc]

Synthetic oil should give the same or very close pressure redings for a given weight.

I think you should first check with a mechanical guage. If it is low then you need to investigate furter.

[91BerettaGT]

Synthetic oil should give the same or very close pressure redings for a given weight.

I think you should first check with a mechanical guage. If it is low then you need to investigate furter.

I am going to do that, hopefully tomorrow.

Anyway I think i should also mention that being the 3400 has 2 spots for a sender, you can't really leave them open, I left another sender in there. It happens to be a switch style sender. So when i'm at idle, I would read Light off (pinned gauge)... But i haven't tested that since the rockers have been installed...

[smilinguy99]

Here's everything I did.

The key to this may be the bent pushrod.

Did you bend the pushrod after installing all these items?

If so, did you check the clearance betrween the bottom of the intake manifold and the top of the rocker on the pushrod end. If the pushrod end of the rocker makes contact with the manifold, you'll have bent pushrods and who knows, maybe damaged lifters too. This is a known issue with the Crane rockers on some aluminum V660s. There isn't much room under there, and that is why the production rockers are shaped the way they are with the bobbed profile and steepish slope on the pushrod end.

Do a search on this forum for information about this. Others have had to grind material away from the manifold to get enough clearance to avoid contact and avoid bending pushrods.

If there is a clearance problem, you may have bent more pushrods and there may be a misalignment of the hole on the pushrod and the rocker that leaks oil. The bent pushrods are likely to be on the intake side.

sg99

[bszopi]

I think I had the original issue with grinding the manifold, although I was using stock stamped rockers on the manifold designed for the roller rockers. Oddly, I never bent a pushrod, but I did manage to cut a pretty decent amount of aluminum out of the manifold, which of course ended up inside the engine. I did replace the lifters as a precaution though, since after I tried several times to start it (hence, the decent amount of aluminum shavings), it was acting as if the valves weren't opening, ie the lifters were shot.

On a side note, my engine NEVER gets below 40psi, and is usually around 55 or so while cruising.