I am at my wits end.

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Gonna sound like everyone else but, I would put those plugs back in. I always believe the $200000.00 a year engineer is smarter than me.
 
Gonna sound like everyone else but, I would put those plugs back in. I always believe the $200000.00 a year engineer is smarter than me.

If engineers made 200k a year, I'd still be in engineering...

I've got a couple of smallblocks that never had those plugs behind the thrust plate. Not saying that can't be it, but they didn't all come with them. Of course, if I was having this much trouble figuring out an oil pressure issue, I'd probably install them "just to see" as part of the elimination process. It's obviously not one of the usual problems at this point, time to start looking for zebras.
 
When you installed the new pump, did you use a gasket? Small blocks don't use one. All the small blocks I've rebuilt had the front plugs installed.
Could it be a faulty oil filter, try a different one and see what happens. Are all the gaskets installed in the angled filter adapter if you're using one.
Take a lifter out and spin it by hand and see how much oil comes out of the lifter galley. I would be worried that there isn't a bunch of oil coming out of the oil pressure port when you spin it with a drill.
The cam bearings could be out of alignment with the cam tunnel feed holes, but you said you checked that.
 
Main bearing clearances too loose? Did you plastigauge them along with the rods? I know I'm reaching but gotta throw it out there.
 
Do you have the right head gasket? LA gaskets have the oil hole for shaft rocker system. Magnum gaskets don't have the oil feed hole.
The head gaskets can be flipped over so the oil feed hole won't line up with the feed hole in the block.
 
Arp main bolts? I had to clearance my pump for these bolts.Wouldnt bolt up flush but looked good at a glance.Just went to the blower thread. I had the same bolts Jack.I had to grind the **** out of the pump for clearance.I sure hope this helps.
 
Not sure what your using for a pump and pick up. I had the same problem 20 plus years ago. I was using a milodon pan with a swinging pick up. The type where you have to put their longer gears in your pump and use their pick up. I used a new high volume pump. Zero oil pressure when priming. Dropped the gears in a standard pump housing All is well. There is a few thousandths difference between standard and hi-vol housing.
 
Pull the heads,if you hqven,t found your problem.Check gaskets,you have blockage....you,ll find it Jack..its just an engine.Happy Motoring.
 
Arp main bolts? I had to clearance my pump for these bolts.Wouldnt bolt up flush but looked good at a glance.Just went to the blower thread. I had the same bolts Jack.I had to grind the **** out of the pump for clearance.I sure hope this helps.

Do you mean ARP studs Pete? Every SB I've done using ARP studs had major interference issues with the pump not allowing it to pull up tight. I usually spot face the main cap .050" on the side where the stud hits, trim the stud down just as short as possible, use a thinner nut and washer (grade 8 of course) and grind a little on the oil pump then it clears.

As for a couple other things mentioned

1. the plugs behind the cam plate. I've torn down engines without them that had no oil pressure issues. I also once had a fresh 360 with low oil pressure and when I took it apart I found those plugs missing and thought aha! I found the problem. Put them in and no change at all. Found the lifter bores worn badly on it causing the low oil pressure. Even though I've seen those plugs make no diff. I still install them just cause.

2. The head gaskets CAN NOT be installed backwards. Anybody that thinks they can must have a block with no dowel pins. Those dowel pins are offset to prevent installing the gaskets backwards. I attached a pic showing them being offset

3. Oil feed to the rocker shafts is only a few degrees of rotation so the cam has to aligned nearly perfect for the oil supply holes to feed the rocker shafts so the only way you will have oil pressure to them is when the engine is in exactly the right spot of rotation and it's different for both sides.

Check out the last picture I attached showing a commonly missed oil galley pipe plug that will cause very low oil pressure if left out. I think you said you checked it so sorry to be repetitive. Just want to make sure.
 

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I have found out every pump should be taken apart and checked. I have never bought a new oil pump that didn't have left over metal in them. It plugs the pump and causes low pressure clean it and they again it fixed my problems 99% of the time.
 
Do you mean ARP studs Pete? Every SB I've done using ARP studs had major interference issues with the pump not allowing it to pull up tight. I usually spot face the main cap .050" on the side where the stud hits, trim the stud down just as short as possible, use a thinner nut and washer (grade 8 of course) and grind a little on the oil pump then it clears.

As for a couple other things mentioned

1. the plugs behind the cam plate. I've torn down engines without them that had no oil pressure issues. I also once had a fresh 360 with low oil pressure and when I took it apart I found those plugs missing and thought aha! I found the problem. Put them in and no change at all. Found the lifter bores worn badly on it causing the low oil pressure. Even though I've seen those plugs make no diff. I still install them just cause.

2. The head gaskets CAN NOT be installed backwards. Anybody that thinks they can must have a block with no dowel pins. Those dowel pins are offset to prevent installing the gaskets backwards. I attached a pic showing them being offset

3. Oil feed to the rocker shafts is only a few degrees of rotation so the cam has to aligned nearly perfect for the oil supply holes to feed the rocker shafts so the only way you will have oil pressure to them is when the engine is in exactly the right spot of rotation and it's different for both sides.

Check out the last picture I attached showing a commonly missed oil galley pipe plug that will cause very low oil pressure if left out. I think you said you checked it so sorry to be repetitive. Just want to make sure.

Thanks for all the suggestions here. I did not know about the plug in front of the dizzy. I don't think it is my problem as I would have oil shooting all over the cam gear area if it was missing and I don't. I will check to make sure.

That's what I always figured as far as the head gaskets. I have the dowels and they are offset. Impossible to install head gasket wrong.

I have ARP main bolts. I will check to make sure there is clearance for the oil pump.

As far as the bearings are concerned, I mic'd them and plasti-gauged them.
If I remeber right, the clearance was about 0.0027 on the mains.

I am going to install a new oil filter today. If that makes no difference I am going to take the oil pump apart.

Lots to check today.

Jack
 
I got nothing to add , but best of luck in your search for the problem.
I'd be well past the salty language point if this were mine.
 
for some stupid reason would the head gaskets be the magnum style without the oil hole. i know its sumtin stupid like that jack if it was obvious u would have found it by now.
 
for some stupid reason would the head gaskets be the magnum style without the oil hole. i know its sumtin stupid like that jack if it was obvious u would have found it by now.

Pretty sure the magnum gaskets have the oil hole also. I used magnum Felpro 519SD's on one of my strokers that had LA Heads & Block. I did this because the compressed thickness was .054 "pistons were out of the hole" The block is where the oil is restricted for the Magnum's, not at the gasket. "block is not drilled to supply oil to the heads"
 
You can check the oil hole without pulling the heads. I believe you have the engine opened up? Pull the cam and run a rod clear down through the heads and visible in the cam journals.
 
Pretty sure the magnum gaskets have the oil hole also. I used magnum Felpro 519SD's on one of my strokers that had LA Heads & Block. I did this because the compressed thickness was .054 "pistons were out of the hole" The block is where the oil is restricted for the Magnum's, not at the gasket. "block is not drilled to supply oil to the heads"
thanks for the info louis i was not 100 percent sure on this as i am not right familar with the magnum engine but i should get my facts straight there is enough bad info out there.
 
Sounds to me like the pressure relief in the pump is stuck open. Take the pump apart and check to make sure it is not hanging up.
 
thanks for the info louis i was not 100 percent sure on this as i am not right familar with the magnum engine but i should get my facts straight there is enough bad info out there.

No problem. I didn't know either until I used them. I had several sets of Magnum Gaskets when I swapped my messed up Magnum Heads for the La's I used on that motor.
 
Thanks for all the suggestions here. I did not know about the plug in front of the dizzy. I don't think it is my problem as I would have oil shooting all over the cam gear area if it was missing and I don't. I will check to make sure.

That's what I always figured as far as the head gaskets. I have the dowels and they are offset. Impossible to install head gasket wrong.

I have ARP main bolts. I will check to make sure there is clearance for the oil pump.

As far as the bearings are concerned, I mic'd them and plasti-gauged them.
If I remeber right, the clearance was about 0.0027 on the mains.

I am going to install a new oil filter today. If that makes no difference I am going to take the oil pump apart.

Lots to check today.

Jack

Your welcome Jack. Your correct that if it were missing oil would be shooting out of it in a big stream. I haven't used ARP bolts so I'm not sure the interference problem that's present with studs is also a problem with bolts but it's easy to check. .0027" bearing clearance is fine. Mine were right about there and it has great oil pressure.

I think after reading all you have checked I'd try swapping the filter too. You never know what it may be defective and not allowing any flow.

Good luck bud
 
DING DING DING DING!!! We have a winner. daredevil nailed it. A big THANKS to pete. One of the ARP bolts was keeping the oil pump from seating all the way. In one of my other threads I said that I could hear oil spraying in the oil pan and that was it. I found this the hard way. When I took the new oil pump off again it was broken. That was a big red flag to me. I found that the ARP main bolt that is hardest to see was interfering. I cured it by grinding a little off of the pump casing. I rebuilt my old pump and tried it in a bucket of oil. It shot oil across the garage. I reinstalled the pump, pan and a new filter and now have 45 psi of oil pressure using a cordless drill that is not turning very fast. I will finish putting the engine back together in the morning, (about 2 hours work) and then I will fire it up.

Thanks to all who had suggestions and good wishes. Some of the suggestions were real eye openers and I checked every one of them.

Jack
 
Now, "screenshot" this thread and send the whole mess to ARP.
 
Way to go Pete. Post some video when you bust it off Jack. We wanna see it.
 
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