Oil pressure loss in cornering

[Robert Dip]

Since I finally got the flatmotor running super, and in making some hard runs to test overall engine performance, I noticed that I lost oil pressure in hard cornering. It was not at any great speed, the oil level was reading normal, so I am questioning the pan baffles. On most of the oil pans I have, there are no baffles in them. I would appreciate any comments regarding this situation. Since I am pulling the engine out to replace leaky gaskets, maybe a pan mod would be in order. Thanks in advance. Robert

[Andy]

I had a 36 pan on my 59A .It would loose oil prssure when stopping or going down hill. I put a correct pan and oil pick up on it and no problems.

[David J]

Your oil is sloshing away from the pickup and your oil pump is sucking air . Old problem with racecars that turn sharp . Look at a custom pan for a road course car and you will see elaborate doors-baffles etc . The stock baffle in 33-34 pans works fine . PS air is a very poor lubricant so you may want to correct this problem .

[4dFord/SC]

Originally Posted by David J

PS air is a very poor lubricant....

Except in Washington

[Old Henry]

Originally Posted by 4dFord/SC

Except in Washington

D.C. that is.

[Kube]

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I have made this repair on early flatheads before. Those baffles are in the pans for a reason Many guys, when installing a high volume pump remove them.
Yep, you need to place the baffle back in place. If you have a later sump, modify the baffle to fit as close as possible to the sump.

[JWL]

The first thing to check is whether or not the oil level is correct in the pan. The dip-stick might not be telling the facts. The second thing to check is that the correct pick-up tube is installed, not defective, and properly attached and located at about 3/8" from bottom of sump. There are thousands of engines operating, without baffles, that do not experience pressure drop during moderate cornering.

[epw1949]

JWL your right on,I put a 34 oil pan on a 35 block,removed the 34 oil pan baffle and the fuel pump baffle,put a short 80 lb oil pump with a 8rt truck pickup tube,heated and bent tube so that it was about 1/2 inch off the bottom of the pan.I used the 34 oil pan gasket.I then went on the barn and asked how much oil is left in the oil pan when going down the road at 55mph? I was told 3 1/2 to 4 qts. So much for baffles and it vents like a 34 and runs fine.I also just had Walt Dupont rebuild a 35 engine for me with the same deal.EPW

[David J]

Now we should think oil pan baffles are a waste of time ? I am giving the person that STARTED this thread credit for being more intelligent than a turnip - do you think he put 2 quarts in and saw the stick reading F so he called it good ? Yes an improper or improperly positioned oil pickup will cause issues but he states all is fine until he corners hard . You can spin that all you want but it still means the oil is SLOSHING AWAY FROM THE PICKUP under hard cornering . That is and always was the PURPOSE of baffles in oil pans .

[296 V8]

Your tire stick to good

[flatjack9]

No one is questioning the value of baffles. That said, not all flathead pans have baffles and this is not a universal problem. He also said he was not doing any high speed tight turns which would be associated with racing. An improper pickup could easily perform properly in straight, level driving, but cause this problem when turning.

[Karl Wolf]

I put in a used engine that lost oil pressure when turned hard, found the cure... Pull down the oil pickup so that it was closer to the bottom of the pan... AND, I could do it through the oil drain hole.
Karl

[Kube]

Originally Posted by David J

Now we should think oil pan baffles are a waste of time ? I am giving the person that STARTED this thread credit for being more intelligent than a turnip - do you think he put 2 quarts in and saw the stick reading F so he called it good ? Yes an improper or improperly positioned oil pickup will cause issues but he states all is fine until he corners hard . You can spin that all you want but it still means the oil is SLOSHING AWAY FROM THE PICKUP under hard cornering . That is and always was the PURPOSE of baffles in oil pans .

Amen.

[JWL]

Sorry, but wrong again---the Ford installed baffles were an attempt to reduce kinetic oil level response during braking. The "G" forces involved in uncovering a proper pick-up, with proper oil level, are relatively high and not easily achieved with the average Flathead powered car, except, during braking.

As someone who has built and raced cars for more than 50 years I have a slightly better understanding of the design criteria than the average turnip. But, each individual should do what he feels is best for his situation. If common sense doesn't fit, ignore it.

[flatjack9]

Amen!

[Kube]

Originally Posted by JWL

Sorry, but wrong again---the Ford installed baffles were an attempt to reduce kinetic oil level response during braking. The "G" forces involved in uncovering a proper pick-up, with proper oil level, are relatively high and not easily achieved with the average Flathead powered car, except, during braking.

As someone who has built and raced cars for more than 50 years I have a slightly better understanding of the design criteria than the average turnip. But, each individual should do what he feels is best for his situation. If common sense doesn't fit, ignore it.

I have more than a little real world experience with these old flatheads as well. I have come to realize there is usually not a single defintive answer to any problem. However, first hand, on more than one occasion, I have repaired the problem the original post(er) is experiencing by simply placing the baffles back in place.

[David J]

I have MAAAANNYYY pictures like this of yours truly if that is to be the gauge of knowledge on such matters . I haven't driven since the mid 90's but am still very involved with a friends sons racing .The pic is from the Wisconsin state spectator drags championship at Lacrosse Fairgrounds speedway in 1988 . The car in the pic had a second design L-88 in it . That means a 427 with open chamber aluminum heads - 12-1 compression and 647 HP at 7,800 RPM . With the stock corvette pan it would hiccup the REAR oil pressure gauge under BRAKING & CORNERING . Not of course under acceleration as all the oil was by the pickup then . Adding 2 more baffles and 1 one way door was the cure as blowing up $10,000 motors is something we liked to avoid as much as possible . You state that Ford only put the baffles in for braking . Never researched that point but would you please explain the difference in the force applied to the oil between braking - cornering and acceleration ? Are you saying that if you go around a cloverleaf fast enough to start your tires sliding this is different than braking hard enough to get your tires to start sliding ? Accelleration with a stock 33 ford is a little shy of that but some hotter ones I would assume can accelerate at the point of slipping tires . You of course have the fact that the outside tires take more load in a hard corner BUT under hard braking the front tires also take more of the load and under hard acceleration the rear tires take more load = wash on that one .Doesn't this kinda end up as a factor of the contact patch of the tires ? Yes I am aware that oil pickup placement is a big factor [ that's why the super late model has a swiveling pickup ] and yes I am aware of different oil pan-baffle configurations on flatheads . Do you think that the huge design change from 34 to 35 in oil pans may have had something to do with controlling the movement of the oil under BRAKING , ACCELERATION & CORNERING ? On the common sense thing again please explain the difference in the force applied to the oil under these different actions . Also please explain the DISADVANTAGES of properly installed baffles .

Originally Posted by JWL

Sorry, but wrong again---the Ford installed baffles were an attempt to reduce kinetic oil level response during braking. The "G" forces involved in uncovering a proper pick-up, with proper oil level, are relatively high and not easily achieved with the average Flathead powered car, except, during braking.

As someone who has built and raced cars for more than 50 years I have a slightly better understanding of the design criteria than the average turnip. But, each individual should do what he feels is best for his situation. If common sense doesn't fit, ignore it.

[Robert Dip]

Thanks David J, for opening up this discussion in a manner that most of us like to see.
I decided not to give comment until I pulled the pan from the engine….who knows what would be discovered. Well, everything is in good order, or even better than I thought. Since this is from a car built in the late 50’s, early 60’s, I couldn’t wait to see the innards.
My smile appeared when the crank # read 1CM, 29A rods, piston bore still has the crosshatched honing marks, so engine is fairly new. Pistons seem to be cast with heavy lower wall thickness…unknown type to me. I did not want to remove the old Navarro heads for fear of damaging them in the process, so my only observations at the moment are from the bottom end. The idea of removing the pan was to replace old dried up leaky gaskets and to replace the original ’39 flywheel that can only accommodate a 9” clutch. With the engine running really well and pulling hard in high gear, the clutch began to slip…..not enough oil on the disc to create this problem, so, as I am there, I may as well replace with a 10” setup. ( using the wider disc as I had questioned on a prior post )

Back to the oil pressure drop….well, as seen on the photo, the baffle is definitely there, and yes, since it is perpendicular to the direction of travel, it seem that for braking or acceleration would do the trick. I never thought that a flathead powered coupe could either brake or accelerated that fast! The oil pick-up, screened can was quite low in the pan, as can be felt when removing the oil dump plug….so I can safely report that it was not up high to catch air. Now getting back to the original problem….it’s still there with everything in its proper place, so what can be causing this and what is the solution???

If anyone has built & tested better baffles for a flathead, it would be interesting to find out. …….still baffled..( no pun intended )…..Robert

[flatjack9]

What oil pump and pickup are in the engine?

[Robert Dip]

Flatjack9...good question....see attached photos...the can is bolted directly to the pump casting....which places the pick-up at the pan bottom. Maybe this older design has flaws ?? although hard to believe it would prevent proper oil pick-up. Robert

[Mart]

Check carefully for hairline fatigue cracks around the top of the pickup can. FWIW the only time I have witnessed loss of oil pressure on cornering was when the oil level was too low. It must be worth checking that the dipstick gives a correct reading when the correct amount of oil has been put in.

Mart.

[Robert Dip]

Mart, I checked carefully as you mentioned for hairline cracks and found none. The metal can is 'unmolested' and in 'as-new'condition. As for the oil in the pan, I'll have to do a test by filling it on the bench and comparing the quantity with the dipstick. FYI, I drained 4 quarts out of the pan before removing it. When I made the oil change, including filling the Ford remote filter, I needed a little more than 5 quarts.

[Mart]

Hard to say then. Those are the most obvious things to check, once ruled out, it's difficult to think what it may be.

Here's a long shot - was it very cold when you noticed the problem? Are you using "thick" oil? Was the engine still cold?

Probably not but you never know.

Good luck.

Mart.

[OLD...BILL]

Lets do a "dip-stick" test, put the dip-stick tube in place, and how much oil dose it take to show full on the stick, looking at the pan where the pickup screen sat in the pan, make me wonder how clean is the screen, can you see light through it ?? With a very limed amount of oil through the screen, and any movement of oil in the pan, would stop flow..... just think may be, not a baffle problem after all ?? ....OLD....BILL ( rank of second turnip )

[Tom Walker]

The problem is the lack of a baffle. The only kind of baffle that works is a horizontal one. All these doors and verticle walls are utterly useless, in fact they often make the situation worse by preventing the oil from returning to the pump pick up.

If you fill a cake tin with water and turn it on its side, a lid will stop the water coming out, verticle "baffles" wont.

[JWL]

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The screen housing canister, where it attaches to the pump casting, needs to be sealed perfectly. Check for possible gasket failure. Also, check the distance from the screen housing(not the screen) to the bottom of the sump.

The M-19 style pump, which has already been mentioned and pictured, is a good upgrade in design. And, as previously mentioned, the pick=up tube would have to be changed.

[Cecil/WV]

Since the pan is long and fairly narrow, it seems to me that the oil is far more likely to get away from the pickup tube upon braking than it is on corners.

[David J]

Was this accelerating or decelerating ? If you let off the gas as you did this it looks to me that your oil could easily surge towards the front and side briefly starving the pump . Post 27 makes a good point about the complete lack of a horizontal baffle to control this and your existing baffle will actually impede the recovery . I am heading to a friends that messes with newer stuff and will take some pics of more modern ways of dealing with this problem . Remember the surge of the oil is rarely straight sideways unless you are maintaining constant speed through a perfectly uniform curve . How often does that actually happen . Interesting problem !!!!!! The pics are of a 33-34 baffle and you can see there was effort put into controlling oil surges in ALL directions .

Originally Posted by Robert Dip

I noticed that I lost oil pressure in hard cornering. It was not at any great speed, the oil level was reading normal, Robert

[Robert Dip]

When do I lose oil pressure…..ok…..normal day, not to cold….I have an industrial building where my cars are kept and stored ( with all of the equipment to work on my cars…so I am fortunate to have this ) and I go for a test drive down the road….not too much traffic…so test runs are easy. I come out of the drive, hang a hard left while accelerating….and notice the oil pressure drop to zero. I have not noticed if this happens in either directions. I use Castrol 20W50 in the engine, but that should not make a big difference….it’s thick enough. The existing baffle is directly in front of the ‘can’ and the screen bottom portion is deep in the pan, practically hitting the bottom….which does not seem right to me….as someone mentioned, there should be a gap ( 3/8th inch was mentioned ) to allow the oil to flow from the bottom into the ‘can’. However, with this design of pump and sump….that’s the way it is….no adjustments in height are possible. The oil level in the pan, in relation to the sump becomes important, and possibly having a baffle parallel to the crank is in order, since there is one already across the sump to take care of stop & go factor. Tomorrow, I shall make this my priority…..there has to be something here that needs improvement.

[flatjack9]

What pressure gauge are you using?

[Kahuna]

IM Very HO, you have the best pump to use. It places the pickup almost center rear of the Pan.
WHen I built my engine, I made a plate (my pan had NO baffles in it) that sits horizontally and above the depression or sump in the pan. It allows oil to move about as it should, but slows it's movement from either moving up the back pan wall, or moving away from the pickup on decelleration.
To me, if you have a cornering issue with pressure, it must be lack of oil (clearly it's not), or an issue with the pump or screen pickup housing.
The plate sits directly below the crank screen in this mockup (may be a bit difficult to see, but it's the only picture I could find).

[Mart]

Could it be a completely different problem??

like a wiring problem - something shorting the sender wire or a bad connection that loses feed to the gauge on left handers?

Clutching at straws here, maybe a mech gauge hooked up temporarily would take any doubt away.

Mart.

[Robert Dip]

Oil pressure guage is a Mallory mechanical, not electrical. Pressure begins at 60 with a cold engine and varies between 20 & 45 in normal use, if my memory serves me right.
Kahuna, I like the screen baffle that you made...how is that working out?

[Cecil/WV]

You might add extra oil and see what happens.

[Kahuna]

Robert
As far as I know it's fine. I haven't had the pan off since I built the engine.

[Robert Dip]

Checking the pan dimensions and the can/screen on the block: After cleaning the pan, I mounted it on the table and gave it a 2-3 degree incline towards the rear to simulate engine in the car, even though the coupe has a forward rake with a dropped axle and lower spring. A few degrees here or there should not be a big deal. I installed the very same dipstick setup and filled the pan with 1 US gallon of Varsol to simulate the oil. As seen on the photo, the dipstick is showing ‘full’. ( full being at the bottom of the arrow ).
The depth of liquid was just slightly over 2 ½”. I also measured the screened can and it measures approx. 2 ¼”. Since it sits at the bottom, and the actual can measures 2”, it leaves this space for the protruding screen and the pan bottom. It would be safe to say that the can is submerged and leaving ¼” on top of it…..providing the car is at a standstill. With a running engine, how much oil is still left in the pan, and is it enough to lower the level to cause a problem….should not, as the engine was designed this way.
The mystery continues……does one add an extra ½ quart of oil to compensate…..make an additional baffle….?? Robert

[Mart]

Don't forget that the volume of the oil pump and pickup will be submerged in that oil. In other words, if you put the 1 US gallon in with the pump in there it would read above full on the dipstick.

I'd be tempted to run with the oil level carefully set to a small amount above the full mark, and monitor for increased leakage. If no problems from leakage, just keep the oil at the full mark or above.

I seem to remember someone having a similar problem and they traced it to the bolts that held the pickup to the pump being slightly too long and not clamping the pickup to the pump properly, allowing air to be drawn in.

Mart.

[cmbrucew]

Robert
You could get a spare pan plug, drill and tap it 1/4" ips, install a male hose adaptor and clear tubing long enough to anchor above the engine. Then you can see the oil level with engine running.

Bruce

Works good
Lasts long time

[OLD...BILL]

How about some large holes on the side of the "CAN" 1/2"-3/4"- or 1" dia. this would give oil aces to pass through the screen and on in to the pump. If the screen is too close the pan to pick-up, and oil moves away on a turn, it should flood the side of the can ??...I looked at five pans in my shop, three have baffles, fixed to the sides with 1/4" X 1" opening at each end at the bottom, and one opening in the center. Another pan has a baffle fixed at the side, with opening in the baffle, one inch away from the side, and is open all the way across the bottom. two others NO baffle, one is a two piece ( truck ) pan
QUESTION How clean was the screen as you took it out ?? ..and how is the baffle in your pan fixed in the pan ??
NOTE: I would stay with your oil pump, as it makes good oil pressure, ..long been a rule here on the Barn " 30 lbs at 30 MPH " life is good. At this point I would pull the intake and clean the lifter valley, from the crud that was in you pan, the valley needs cleaning
Also I think you oil pump is "A DEMOCRAT " can't turn left and keep working ....OLD....BILL

[OLD...BILL]

How about some large holes on the side of the "CAN" 1/2"-3/4"- or 1" dia. this would give oil aces to pass through the screen and on in to the pump. If the screen is too close the pan to pick-up, and oil moves away on a turn, it should flood the side of the can ??...I looked at five pans in my shop, three have baffles, fixed to the sides with 1/4" X 1" opening at each end at the bottom, and one opening in the center. Another pan has a baffle fixed at the side, with opening in the baffle, one inch away from the side, and is open all the way across the bottom. two others NO baffle, one is a two piece ( truck ) pan
QUESTION How clean was the screen as you took it out ?? ..and how is the baffle in your pan fixed in the pan ??
NOTE: I would stay with your oil pump, as it makes good oil pressure, ..long been a rule here on the Barn " 30 lbs at 30 MPH " life is good. At this point I would pull the intake and clean the lifter valley, from the crud that was in you pan, the valley needs cleaning
Also I think you oil pump is "A DEMOCRAT " can't turn left and keep working ....OLD....BILL

[Robert Dip]

OLD….BILL……thanks for the interesting comments. Here are the photos of my oil pan showing the baffle configuration. Could it be that the oil pump sucks up all of the existing oil in the ‘can’, and not enough can refill it in tight turns…interesting theory. Maybe making longer elongated slots on the lower portion of the ‘can’ could be the trick…..keeping the slots on the lower side to prevent picking up air….Great food for thought…..in fact, I may just do that. On the sludge factor, the valley at the lifters is pretty well clean, lots of black oil, but no sludge. There was a bit of sludge in the deep part of the pan, but not enough to cause this problem. The screen had no blocked areas…just dirty oil. This engine has low mileage as seen from the cylinder bores, but the car was a garage find stored for a great many years, around the mid 60’s, and black oil in a flathead seems to be common. ( please possibly correct me on this one ). It may also have been caused by the rich mixture that I originally had and now corrected. ( no gas in the oil, for those who would comment….as I changed the oil more times than I actually drove the car ) Since the intake and pan are now removed, cleaning it well may give me light brown oil as a reward.

[Mart]

Put it back together, keep the oil level up and make sure you NEVER look at the gauge when cornering. That's it - just keep your eyes glued to the road.

Next!

LOL

Mart.

[Robert Dip]

Mart.....I am there.....right on......can't loose any more sleep at night over this...I got a race to prepare for...a highboy Flathead Deuce Roadster to beat..at the 1/4 mile back road, and it's a straight run. A case of beer is at stake....big time...teenage girl with a bright red scarf is the 'flag girl' ....after all, this is the 50's, isn’t it.....right?

[Robert Dip]

Just a word of thanks for all help in this matter. I'll slot the lower portion of the can, see if 1/2 quart helps, and when I take the car out in the spring, I let you know how it works out. A lot of times, it's a little unseen thing that causes problems....we'll see.

Much appreciated....Robert