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**JoeHall** · 05-06-2016, 06:35 PM

Sounds like gasoline mixed with the oil. Most likely cause is NOT flooding, but rather a faulty fuel pump. Smell the oil on the dipstick for gasoline smell. With a faulty mechanical pump, it will continue to pump gas into the oil. I'd remove the mechanical fuel pump and install an electrical pump, at least for now.

I would not run it anymore than necessary till the problem is solved. Gas thins the oil and makes the pressure drop. It also destroys the lubrication properties of your oil. If there is gas in the oil, and your motor bearings are not shot, they soon will be, if you continue to run it that way.

**wdills** · 05-06-2016, 06:52 PM

The car has an electric pump. The flooding occurred several months ago and the oil was changed immediately when the gas was discovered in the oil. I should be clear that we could smell gas on the dip stick but there was no increase in oil level so it was not like we had a lot of gas in there.

If the gas did damage the bearings or if something else has damaged the bearings and they are failing shouldn't I be able to see some shiny stuff in the oil when I drain it tomorrow?

**StudeRich** · 05-06-2016, 07:53 PM

You would be more likely to see the metal particles inside of the Filter you removed. If you still have the Cartridge, you may have to cut it open.

All things considered I am leaning toward the cause was running with No Galley Plug, the "Mechanic's" fault. The Oil Pressure is now so low that I believe the Cam Bearings could be worn, also Rods and Mains.

I wonder if there is a chance there are more Plugs loose or missing? The only thing with that is, that I believe the Dist. Tower Plug is the Only internal Plug, so if there is No Oil leaking they must be good.

**JoeHall** · 05-07-2016, 02:52 AM

When you change the oil, put 20w50 in it. That will give you the highest oil pressure you are gonna get, and it is not going to hurt the motor, regardless of what anyone tells you. I used nothing but 20w50 for many years in Studes.

**joncon** · 05-07-2016, 03:15 AM

I use 20w50 in all my older vehicles. Never had any problem. It raised the oil pressure from 10 t0 20 at hot idle in my 33 Ford.

**jnormanh** · 05-07-2016, 03:39 AM

If the only symptom is low oil pressure, no bearing knocks, no blue exhaust smoke, there may be nothing seriously wrong.

Engines need oil to the bearings and rings, but it doesn't necessarily take a lot of pressure to get enough oil. For example, the Lotus V8 normal oil pressure is 5 psi. They marked the gauge L-N-H because they thought buyers would be upset if they knew the real oil pressure.

**jackb** · 05-07-2016, 06:22 AM

If you've seen that amount of oil pressure drop, I'd be thinking original rebuilding problems too. The pressure has now changed so dramatically, that engine failure is a possibility (probability). With all the other work you've done on the car, just driving around town now (that's all you can safely do), I'd open the engine up from underneath and at least see the bearing situation....

**Phatfenders** · 05-07-2016, 08:35 AM

I recently experienced a similar low oil pressure. To rule out a gauge problem with my electronic oil pressure gauge. I plumbed in a mechanical oil pressure gauge and went for a long drive. There was about 12 psi difference between the gauges. My hot idle pressure showed 20 psi with the mechanical gauge and appears to be less than 10 psi with the electronic gauge.

**colt45sa** · 05-07-2016, 09:24 AM

Originally posted by wdills View Post

Took my 61 Hawk out for its first shakedown cruise today after completing the restoration. The 289 partial flow was rebuilt about 3 years ago. The engine was run after the rebuild. The shop left the plug in the distributor tower out after the rebuild. Folks here on the forum guided me through the installation of the plug. After the plug was in the car had very good oil pressure with straight SAE 30. If I remember right it was about 50 psi cold and 20 psi at hot idle. Once the mechanicals were all taken care of I took the car apart and did the cosmetic work. Everything was painted and put back together. The engine has only been run occassionaly since is was put back in the car. During the early running after the car was going back together I got a piece of trash in the needle valve. Took a while to identify and resolve the problem. The engine was run quite a bit with the needle valve stuck and the engine flooding. During this time I discovered gas in the oil from the flooding. Changed the oil immediately and re-filled with 10W30. Since then the car has only been run a little when I would move it in and out of the shop.

Cold oil pressure is now about 25 psi and it drops to about 6 or 7 when idling at full temp. I didn't think much about it because I knew the manual only gave a 40mph oil pressure and I had no idea what that RPM would be.

Driving it today at full temp gave me about 12 psi at 40mph which was about 1500 RPM. At 60 mph and 2500 RPM I was getting about 15 psi.

I pulled the relief valve and it was nice and clean and I was able to slide it right out. I also disconnected the oil filter line and plugged the port in the block. I added a bottle of STP to the oil. Nothing made any difference. Finally I checked my gauge with a test gauge to verify it was reading correctly.

The only thing I can think of is to try going back to SAE 30, but I can't believe this would make much difference.

How long will these things last with such low oil pressure?

Any suggestions on other things to look for?

Wayne

My brother's first car was a '53 Starliner. The engine never had more than 10lbs of oil pressure. He drove it everywhere for several years and it never gave him any problems. Smokey Yunick says you need 10 lbs of oil pressure for every 1000 rpms.

**rstrasser** · 05-07-2016, 10:11 AM

Wdills;
I don't understand how just by sitting a engine could go from 50 LB oil pressure to about 12.
If the plug in the block by the distributor is not leaking; I would install a new oil pressure relief valve and spring in case the spring is too weak or the relief hole is too big.
The book says not to shim it.
20W50 oil is a good test but not a cure all. The engine should produce 40 LBs oil pressure at 40 or 50 MPH in high gear.
Ron

**wdills** · 05-07-2016, 03:39 PM

Well I think the question is answered. Today while doing some checks it developed a rattle / knock out of the bottom end when I increased the rpm and then let it drop suddenly back to idle. Guess the engine is coming back out.

**JoeHall** · 05-07-2016, 03:42 PM

Originally posted by wdills View Post

Well I think the question is answered. Today while doing some checks it developed a rattle / knock out of the bottom end when I increased the rpm and then let it drop suddenly back to idle. Guess the engine is coming back out.

That's a kick in the nads. It may or may not be due to the oil plug fiasco. It may be due to something else he goofed up during reassembly.

**Warren Webb** · 05-07-2016, 05:17 PM

When I first started reading this thread I thought of the oil pressure relief valve too. But if your hearing rattling/knocking noise too now I think you've found the problem. Sorry.

**StudeRich** · 05-07-2016, 08:28 PM

Originally posted by colt45sa View Post

My brother's first car was a '53 Starliner. The engine never had more than 10lbs of oil pressure. He drove it everywhere for several years and it never gave him any problems. Smokey Yunick says you need 10 lbs of oil pressure for every 1000 rpms.

That is great for an old Car with a lot of miles, but a fresh Rebuild, no Way.

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