Losing Oil Pressure

[JSeery]

The oil pressure should never drop to zero. Whatever it is at idle is the lowest it should drop. There is a pick-up problem somewhere if this only occurs with stopping or turning. I know you have checked it out, but something is being overlooked somewhere. Good Luck.

Edit: Think about the guys racing these engines on a dirt track, with this type of issue they would never have oil pressure!

[TomT/Williamsburg]

It is not unusual for a warm 59AB engine with a stock oil pump to go to zero oil pressure when coming to a stop and go to idle after a good run. If I am wrong others will chime in but I have had several other engines do the same thing. Never an 8BA engine, or at least an 8BA oil pump engine, however .....

[BILL WZOREK]

Tom
What harm would come on putting 5 Qt's of oil in and run around block , never know stranger things have happen.

[TomT/Williamsburg]

Gotcha Bill - just trying to see where the engine is at in this situation. Taking baby steps sort-to-speak! LOL!

[Ol' Ron]

Our track engine had an extended pan under the starter with the pick up in it. Ran 2 oil filters as well so we had almost 7 qts of oil in the engine

[tubman]

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Ol' Ron,

OK, I'll play. I built a special pan for the 331 hemi in my dirt car. With 2 filters, it took 14 quarts. I used Mobil-1 20-50. An oil and filter change was north of $100!

[JSeery]

Yep, same here. Oversized pans and baffles, but I never considered "0" oil pressure normal.

[Mart]

Baby step another half quart in there, Tom. If you still have oil pressure dropping to zero then there is another problem. Oil pressure should not drop to zero under any circumstances.
Do you have mega powerful brakes?
Does your pan have the crosswise baffle?

Mart.

[trainguy]

Tom,How about the bypass valve under the intake .On my 46 I my oil pressure dropped and was 0 at idle but went to 5 lbs at 30 mph.Suspecting the bypass to be the culprit I disassembled it cleaned it and reassembled.Problem solved!Did,t find anything,must have been stuck open,or something held the ball off the seat.

[chuck stevens]

Tom, I have had an oil pressure problem with the 40 I just finished. It's a 8BA, has good oil pressure when cold but after fully warmed drops to zero at idle. I droped the pan and pulled the pump out to look over the check valve. It all looks fine. It has a NEW Schenider cam, and NEW cam bearings, as well as rods and mains. I'm at a lost!!It will get driven with 20-50 Brad Penn oil in the spring, come h--- or high water. Maybe I could raise the idle to 1200, Chuck S.

PS It has the high volume pump too.

[TomT/Williamsburg]

Hmmmmm - don't know as yet what what my problem is if anything but I did not have this problem before. Can't begin to think why we are not getting oil pressure. I have not had good luck with high volume oil pumps - I just use the stock ones and from what I understand the stock 8BA pump is a higher volume pump than the stock 59AB unit. What I do know is that I did not prime my pump this time around so perhaps it has lost its prime. Regardless, if I can keep 4.5-5 qts of oil in it and the pressure stays up and no other issues, then that is what I will do. I really do not want to pull this engine apart from underneath. I would rather install the hot 59AB flattie I have coming together in it than mess with this one and it has an 8ba oil pump with a modified pan for the pickup.

Let's keep checking in with one another and maybe between the two of us we can figure this out.

[Andy]

My son was loosing oil pressure in his daily. It was the gauge.

[TomT/Williamsburg]

OK - took her out again today after adding another 1/2 quart of oil. She ran well, did not miss a beat but the gauge did register zero oil pressure a couple times. I am now suspecting the gauge. I have another and will swap it out hopefully this weekend.

I hope that is it - if not, I will have to go to Plan B as I will have exhausted all of the "non pan removal" options.

[hotcoupe]

tom and others, i pulled wrenches for four years while in the service and one thing that i learned real quick when trying to trouble shoot a problem - always try the easiest things FIRST! i have a fresh 239 in my truck and i experienced low oil pressure at hot idle. my first thought was the pump, but i decided to pull the intake and block the by-pass valve. BINGO! the engine has 20 lbs. at hot idle now. sure beats laying under the truck pulling the pan, and then trying to get everything sealed back up.
tom

[sidevalve8ba]

Tom,
I hope you get this problem sorted. Let us all know what you find is the problem or what cures it.

[TomT/Williamsburg]

Just an update - changed oil pressure gauges and got more of the same result. Will start removing the intake tomorrow ......

[Willit Stop]

I had a similar problem because someone in the past assembled the oil pump wrong.At higher RPM's or driving up a hill,the pressure would drop.You might try parking the car on a steep uphill,check the gauge,then turn it around to a steep downhill and check it again.If there is a change in pressure,your pump is drawing more air than oil when the oil is mostly in the front of the pan and there is a leak on or around the pump. Hope this helps.Good luck.

[TomT/Williamsburg]

OK - finally got warm enough to remove the intake and see what's up. I can see nothing really bad in the lifter valley. Everything looks normal. I removed the baffles for the return holes and they had some residue on them. I cleaned them up, cleaned around the return holes as best I can as well. I did notice that the baffles have an "F" on them. I am assuming that means front and both baffles had the "F" on the back side. They are now installed with the "F" towards the front. I do not know if that could make a difference as they look the same either way?

I have removed the relief valve and the ball at the end seems to have a flat spot in it. I do not know if that is normal? There was also some oil residue where the ball seats. I've cleaned that up and I will check my other engine to see if that ball has the same flat spot.

I will post some pics as soon as I can ....

[hotcoupe]

All relief valves that i have come across had the flat spot that you referenced.
tom

[TomT/Williamsburg]

Thanks Hotcoupe - I did pop the one out from another engine and it had the flat spot as well.

BUT - what I did find when I removed the other valve and spring is that it is much heavier and longer than what I had in my car. The pic has the one that was on my car with the oil pressure problems on the left, the one I took out of my "hot rod" engine on the right. The spring on the right is both physically longer and a heavier spring but it did have an 8BA oil pump installed which is of a higher volume that the 59 engines.

Were there different springs for the higher volume oil pump in the 59ABs? 8BAs do not have this setup, correct?

To me, the lighter the spring the faster/easier the ball can be moved off its seat, lowering the oil pressure. Maybe I should be using the heavier spring?