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Before rebuilding my 324 engine the oil pressure ran between 40 and 50 cold and not lower than 40 when warmed up, so when rebuilding I didn't replace the pump. With engine on the stand and with oil in it I could never get any oil pressure (using an add on gauge) but could see oil flow from back to front since the intake nor the valley plate had been installed then. I cranked the engine today and can only get a reading of about 15 and have lots of lifter noise. Could either the oil pump pressure relief valve or the ball valve in the filter base be stuck open causing low pressure? Oil is supposed to go through the filter first then to crank, cam and right gallery to lifters then to left gallery and lifters. Any help will be greatly appreciated.
Did you do the rebuild your self and replace the galley soft plugs? Often the back galley plug is not put in after the block is dipped or cleaned. This will give you low oil pressure as it is a 1/2 open hole that drops all your oil into the distributor galley. Often this happens when the machine shop isn't used to doing early Oldsmobile's.
As side note the top plug needs a 40 thousands hole in it to dribble oil on to the distributor gear, often that is also a missed item. If it is missing you can install it from the top without having to pull the whole engine out to get to it, kinda a pain but doable. Doubtful that your oil pump went bad during the rebuild I would look else where.... Tedd
I almost didn't see this post because of the forum you picked. You will have better luck and more views posting in the vintage forum or some other forum that is more related to your issue. Good luck in your build and let us know what you find it will help others doing the same thing coming behind you..... Lost in the fifties... Tedd
Thanks for your info on pump and future posts. It sounds as if the intake will have to come off again for me to see the galley plugs you're speaking of. Are the plugs inside the block? I have a 55 shop manual, but it doesn't go into detail about the plugs. From what you're telling me I think you've isolated my problem. Once I find out and correct it, I'll be posting on some of my other blog sites and those on my face book page in case someone else has the same problem.
Thanks again!!
Forgot to answer your question. I did do the rebuilding after the machine shop cleaned and did all the boring, etc. and had to replace a couple expansion plugs in the heads that needed to be replaced, but the shop didn't bother with.
Where are the gallery plugs located and how to I get to them? The only diagram I can find shows the galleries going through the crank into the cam and up to the rocker shafts. There is no reference to where the plugs are located. On SBC engines it seems that there are plugs on the front and rear of the block. However, when the engine was on the stand and I was running the pump with a drill, no oil came out to the back of the block, so it would seem to me that the Olds block is not made like the SBC. I'm hoping that the plugs can be located by removing only the intake and valley pan cover.
Thanks again for your help.
Ponder pull the distributor and with a dentist mirror you should be able to see the galley plug down in the hole. It's hard to get reach but doable if you are nimble. Use your index finger and feel for the hole. When you install it be sure you have something to fish it out if you drop it. I don't think the plugs are steel (could be though) but that one needs a 40 thousands hole in it's center be sure to drill it first.... Let me know how this comes out it's been a while sense I had this problem but it comes up quite often when you aren't used to working on first generation Oldsmobile"s.... Tedd
Whew, what a relief!! I was afraid the engine might have to come out. Thanks a million for your help. I'll be sure to let you know how this comes out. I can understand a machine shop not being familiar with early engines, but the plug had to have been removed during clean up, so it seems to me that any good mechanic or machinist would put back what he removed. Any way, this sounds much simpler that I'd expected.
Thanks again,
Eddie
I've looked in the distributor hole with a dentist's mirror, but can't see a hole where a plug should be and can't reach it with my finger. I can see a plug in the very back of the block a little to the driver's side of the oil pump shaft, but since there was no oil coming out of the back of the block with the drill running the pump, I don't think that's the one you're speaking of. There doesn't seem to be a hole in that plug. I bought an old distributor, ground the teeth off the gear and have run the pump with that. I turned the crank with a wrench to the point where the oil passage in the cam shaft would line up with that of the crank passage and found that there is oil coming up to the valve train, but still have only 15 lbs pressure. If the plug you speak of was missing would any oil come up to the valves?
Here is a thread about the same issue (maybe not though) see if this helps. If it's not the galley plug you may have to go deeper in to the engine...... Tedd...https://classicoldsmobile.com/forums...l-rebuild.html
Sorry, I got busy doing other things and forgot I was going to try and get some photos. Tedd, I'm more familiar with the 330-455 engines so please let me know if these photos are of the right thing. My engine was pretty gummy inside. I did shoot some brakekleen on it to try and clean things up a bit. I started with the back of the engine and have a photo of what looks like a freeze plug on the drivers side of the block, under the distributor location. I removed that plug and could see a threaded plug with what looked like 1/4" drive square hole in the center of it. I used a 1/4" drive ratchet and extention to try and remove it, but goofed and didn't notice I pulled a cheapy extension out of the tool box and broke it in the plug. But if your looking down the distributor hole look to the front of the engine and you should see this plug with a square hole... or an empty hole if the plug is missing. Let me know if you have any questions about the photos. I was taking them with a flashlight so if something isn't clear I can try again when the sun is out. John
Back of the block Underneath what looks like a freeze plug Looking through the hole where the freeze plug looking thing was removed. Here's the plug I believe Tedd was describing. Looking down the distributor hole, I've got the flashlight in the valley area. Look just right of the 6:00 O'clock position and you can see the plug with the square hole in it.
Thanks again Tedd! I did find the plug - it's not missing, but can't tell if there's a hole in it. At any rate, this isn't my pressure problem. Yesterday when I posted that oil was coming to the valve train that was correct, but only for the odd side of the engine. Today I removed the valve cover on the even (driver's) side and rotated the crank at least two revolutions while steadily running the oil pump (CCW), but no oil ever came up on the even side. The galley diagram (for what it's worth) in the shop manual shows the oil to be coming off the 2nd cam journal (from the engine front) to the odd side and off the 4th journal to the even side. That has to be the opposite of reality. There isn't a left and right on heads or rocker shaft assemblies. No matter which side either is placed the oil should come off the 2nd journal to the even side and 4th to the odd side. The 4th journal is where the oil came out on the odd side yesterday. Now I'm wondering if the cam bushing was correctly installed in the block, or if it has the gallery covered up on the 2nd journal feeding the even side. The plot thickens.
Eddie
I know this has been covered before, but I can't seem to find it. Does anyone have a diagram of the complete oiling system on a 324 from the pump all the way up to the rocker shaft? I don't think I'm getting proper oiling to the rockers because they don't seem wet. There is a little oil in the trough at the bottom of the head, but not much. I'm concerned that there may be some restriction either in the head gasket or cam bearings to reduce flow.
I know this has been covered before, but I can't seem to find it. Does anyone have a diagram of the complete oiling system on a 324 from the pump all the way up to the rocker shaft? I don't think I'm getting proper oiling to the rockers because they don't seem wet. There is a little oil in the trough at the bottom of the head, but not much. I'm concerned that there may be some restriction either in the head gasket or cam bearings to reduce flow.
These valve trains don't oil like later Olds ('65-up)
Metered oil is provided to the hollow rocker shafts.
The shafts have holes in the bottom where each rocker rides.
That's all the oil the top end gets. No oil thru the push rods.
If you're getting any oil to the rocker arms, you're good to go.
You won't get the deluge of oil at the top end like you would in a later Olds or a Chevy.
Were the crankshaft rod and main bearing clearances measured during installation? What were the clearances? Wouldn't expect a known good oil pump to be the problem.
I don't know the clearances, but the engine was rebuilt less than 5,000 miles ago. The oil pressure is steady at 45psi. I thought that there would be more oiling on the top end.
These valve trains don't oil like later Olds ('65-up)
Metered oil is provided to the hollow rocker shafts.
The shafts have holes in the bottom where each rocker rides.
That's all the oil the top end gets. No oil thru the push rods.
If you're getting any oil to the rocker arms, you're good to go.
You won't get the deluge of oil at the top end like you would in a later Olds or a Chevy.
Originally Posted by carnutz
I don't know the clearances, but the engine was rebuilt less than 5,000 miles ago. The oil pressure is steady at 45psi. I thought that there would be more oiling on the top end.
Charlie Jones is very correct. The oil comes up through a hole on the heads, through one or two rocker arm stands, through a hole in the rocker arm shaft and to the rocker arms. It is a pressurized oil supply. This is different than the later Olds engines.
April 6th, 2019, 08:26 AM
... Let me know how this comes out it's been a while sense I had this problem but it comes up quite often when you aren't used to working on first generation Oldsmobile"s.... Tedd
