Oil Pressure

I have a 64 Daytona with a 259 automatic. Last summer we got cought in stop and go traffic for about an hour. The car did not get hot thanks to the new radiator I put in it. Towards the end of the traffic jamb, the oil pressure dropped about 15 lbs. I have since changed the oil to 10w30 and cleaned the oil pressure releave piston and spring. The pressure has not come up. Should I replace the srping and piston with a rebuild kit from Stude Inter.? Any help would be welcome. Frank Smith, Napa CA

Frank Smith, Napa, CA

[StudeRich]

I don't want to make you overly concerned ie: (scared to death)! [:0] But...the truth is, I have found from experience that you need to carefully watch that pressure, if it always ran 40 to 70 PSI like most '63-'64 full flow engines and suddenly lost that much AT THE SAME TEMPERATURES (IMPORTANT)! Or if it continues dropping. Then depending on how low it is, I would be worried about the cam bearings if you do not know that at the last overhaul they were changed or it was professionally REBUILT or the engine has less than about 60,000 miles etc. In hot country like yours and if you have a worn engine, I would try 20W-50, but of course if you read the no zinc oil posts, I guess now-days you would have to use Chevron Delo 400 15W-40 or Shell Rotella "T" Diesel oil for a flat tappet cammed engine. [^]

StudeRich
Studebakers Northwest
Ferndale, WA

[Roscomacaw]

[Mike]

On the full flow blocks, there are relief and bypass valves, in the oil filter adaptor, in addition to the oil pressure control valve at the front of the block. The valves in the adaptor can leak badly; and sometimes even come loose. The relief valve is effectivly on the output of the oil pump; and dumps oil directly back into the pan through a 1/2" hole in the block. They probably cause a lot of low oil pressure troubles.
You might want to unbolt yours from the block and check it out. Buy a new gasket for the adaptor. Check to make sure the bolts don't bottom out in the block with the washers and gasket you use.
Mike

[stuvw2mny]

Whenever the dash oil pressure guage shows a drop most Stude owners go almost into panic, fearing their engine is about to come apart. Mike's advice (previous post) is very good and definitely worth following. If original, the items he is talking about are 40 years old.

Also, I would remember that the dash guage is also 40 years old and automobile guages are, and always were, extremely inaccurate. In mechanical guages a small piece of carbon or ? might get loose in the engine and plug the guage. Since my newest Stude is only a 1962 I don't know if Studebaker finally in 1964 went to an electrical sender for the guage. If so, that sender needs checking. Before yanking the engine out for an overhaul or other drastic action (I wonder how many owners have done that because of inaccurate guage readings) I would get another oil pressure guage and connect it directly to the engine. There should be a 1/8" pipe plug fitting easily acccessible at the front of the left head for such a direct connection.

In 40 plus years of Studebakering and Porsche-pushing I have seen almost no instance of different oils having much effect on oil pressure. This includes the addition of STP which Studebaker Corp recommended in the 1960's - partly because they owned STP. Yes, there are sometimes some short-lived improvements. In the early days the recommended oil for Studebaker engines, after the break-in period, was 30 weight oil. The move to multi-viscosity oils was a benefit for year-round driving, but considering the age of most Stude engines, I would be looking for no less than a 20W-40 oil. Do not use 10W-40 or 20W-50 oils because SAE tests have shown too much viscosity-improver can promote sludge. The operative word there is CAN. If the car is driven only in the summer, 30 weight oil might be better.

[Flat Ernie]

My dash-mounted gauge seems to be intermittently erratic (how's that for redundant?) - I think the gears in the mechanism are dirty, but sometimes it wants to stick at a low pressure reading, but if I tap on the gauge, it moves up. I put a direct-reading mechanical gauge right on the engine to give me a bit of peace of mind for when I want numbers instead of graduated lines on the gauge...

The point is, the guages are also old & rarely (if ever) rebuilt/renewed (because it's too darn expensive), so they can be sticking, sluggish, or plugged...

Daddy always said, if yer gonna be dumb, you gotta be tough & I'm one tough sumbitch!

[Roscomacaw]

[John Kirchhoff]

I once had a guy in the know say the main reason they stopped putting actual numbers on dash instruments was because invariably someone would get all worried because his temp guage said 160 when in actuality the temperature of coolant was right but the guage was wrong. With just lines and no numbers, the driver could tell if something suddenly changed but not have the opportunity to go bonkers over an actual number display. He said it sure saved a lot of warranty work in checking and replacing guages.

[stuvw2mny]

John, you're absolutely correct about guages/warranty costs. The next step was warning lights, appropriately called idiot lights. I think all of us appreciate guages on our Studebakers.
There were 2 books written at nearly the same time in the 1960's. One was titled "The Incompetent American Driver" and the other was "Unsafe at Any Speed". One pointed a finger at the driver and the other pointed a finger at the car. Need I say which one was forgotten and which one became famous? Sorry for the digression.

[raprice]

A few years ago, there was an excellent discussion on oil pressure in the Cooperator section of Turning Wheels.
One of the answers to lower oil pressure was to switch to a heavier oil such as 20W-50. I had the same problem of oil pressure dropping to 20psi and I had difficulty getting the pressure back up to 40 when driving and the engine was hot.
I followed the advice of switching to 20W-50 and that seemed to do the trick.
Of course, if you have bad rings, that's another story.
Idling at 20psi is fine.
Rog

'59 Lark VI Regal Hardtop

[StudeRich]

I believe you may be wrong about the 20W-50, I recall that article saying it's only the 10W-40 thats a problem. And I don't know anywhere you can find that rare combo 20W-40 ?

The bottom line is, that none of this matters because it's all 2005-6 info. In 2007 none of the above oils will work in our cars, only Redline Oil, Zinc additives or Shell Rotella "T" 15W-40, or Chevron Delo 400 15W-40 Diesel Oil.

quote:Originally posted by stuvw2mny

I would be looking for no less than a 20W-40 oil. Do not use 10W-40 or 20W-50 oils because SAE tests have shown too much viscosity-improver can promote sludge. The operative word there is CAN.

StudeRich
Studebakers Northwest
Ferndale, WA

[John Kirchhoff]

Stuvw2mny, I made a point to forgot "The Incompetant American Driver" book because it hit a little too close to home. Being the average American, "Unsafe At Any Speed" made me feel much better because it absolved me of any responsibility. Detect any sarcasm there???