Oil pressure dropping on right turns

The holes are something to think about if I ever have the engine apart again. I would think it would be a job to get all the chips out if I tried to do it in place. I am going to have to talk with the builder and find out exactly what he did in there - or pull the side cover off and look.
 
Years ago,I built up an"A"block with a 33 C crank fitted with 1-11/16" mains & heavy steel front & centre main caps.I used a special oil pump with 8BA gears& pressure relief valve.It ran about 50#oil pressure with a drilled C S.I had also drilled several 5/8"holes in bottom of valve chamber.I used NO dipper tray & it ran great & did not drop oil pressure when making RH turns.I was also running an original 2-port Riley & large zenith updraft on it.Wish I had kept it as it was around 80 HP.
 
I know this post is a little late, however, I just finished making a trap door baffled oil pan. I put it in about two weeks ago. There is no dipper tray as the engine has a full pressure system. I am using the Stipe oil pump. I got the starting ideas for this from Jim Brierley's book.
On the trip to Hellertown last Saturday, I could not see any drop in pressure no matter how hard I went around right corners or the highway exit ramps.
Thanks to all who have posted suggestions to me.
Thanks
Dick
 

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No worries ! ...... All race tracks, in the USA are, "Go Fast - Turn Left, Go Fast - Turn Left.......".
It's different, overseas, you would be in trouble !
MIKE :) (mikeburch)
 
Hey Dick,
Thanks for the great follow up and pic , better late than never...they say :) ! Yeah, I agree that Jim B book has done a lot to help people in this 'hobby' !
I'm wondering, after reading entire thread, never said whether you had a dipper tray or not ? It you did not have a dipper tray when problem existed, I could easily see why problem. When pressurized , dipper tray can be left and inch sized holes drilled in tray to allow quick draining of oil to bottom of pan..then no problem. That's what I did successfully, without trap door system necessary. I would use trap doors if racing tho..
There are also adventages to leaving original tray with inch holes drilled.

BTW...I bought one of original stipe oil pumps for my B...pricey, but GOOD :D ! Pay for quality !!
 
Hardtimes:
It had the dipper tray when I first had the engine built and yes, the problem did exist. Ora at Schwalms put 1/2" holes around the edges of the tray. With the trap door baffles I had to remove it. When I was racing my Lotus, I not only had to run a baffled pan but also had to run it 1 qt. over full. So, when I built this, I went all the way this time. The dippers on the rods were effectivly plugged with the full width insert bearings.
 
bettlesr said:
Hardtimes:
It had the dipper tray when I first had the engine built and yes, the problem did exist. Ora at Schwalms put 1/2" holes around the edges of the tray. With the trap door baffles I had to remove it. When I was racing my Lotus, I not only had to run a baffled pan but also had to run it 1 qt. over full. So, when I built this, I went all the way this time. The dippers on the rods were effectivly plugged with the full width insert bearings.
Click to expand...

Thanks for this helpful info and again for the picture of your solution ! I'm in the stage of deciding what to do for oil pan work at this time, so very timely:) !
I'm going to use modified V8 flathead pump this time. I'm thinking of making sump pickup device CLOSE to pan bottom with screen. I've seen other 'varieties' for A/B pan baffle systems. Yours looks a bit different, but nice work ! Maybe copy it,eh :D
 
hardtimes:
If you need them, I have the cad drawings of the pieces I made. They required some trimming to fit the exact shape of the pan but they are close. I used 3" long pieces of 3" ss piano hinges. There is about .050 clearance below the doors so the pan drains properly when changing the oil. I also removed the hinge pin and replaced it with a thinner piece of ss wire bent it the ends to limit the hinge to swing a max of 45°.
 
MikeK said:
Yes! That would permit oil mist from the crankcase to flood the chamber. Something that is NOT happening on an A that has been converted to pressure. Adding those large holes would be an excellent idea.
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Right Mike, look at a Model T, 2 1/2" holes and no pump to begin with. There has to be some oil in the chamber or the guides will soon wear out and the valves will be really noisy. I fixed one for Pete on here that was done exactly as you describe and the guides were all worn with 2 worn our .070. Talk about some noise :eek:.
 
bettlesr said:
hardtimes:
If you need them, I have the cad drawings of the pieces I made. They required some trimming to fit the exact shape of the pan but they are close. I used 3" long pieces of 3" ss piano hinges. There is about .050 clearance below the doors so the pan drains properly when changing the oil. I also removed the hinge pin and replaced it with a thinner piece of ss wire bent it the ends to limit the hinge to swing a max of 45°.
Click to expand...

That would really be nice of you and appreciated, as I'm not much of a fabricator:) ! That way, I could be working my B pan while the man bores for 4" pistons ! I'll send you PM !
 
My A does exactly the same thing. When cold, the low pressure lasts MUCH longer than when the engine is hot. My theory is that the pump is filling the valve chamber and the thicker oil (15W-40) takes longer to run through the overflow tube and back to the pan so the effective level at the pump is lower. When the engine is hot, it lasts only a few seconds. When cold, it can last a minute or so after a significant turn. I TRY to let the engine warm a bit before driving off... or take it VERY easy on right turns until it's warmed.

SD
 
I have found that the dipper tray stops the oil from surging away from the pump better than anything, because there is nowhere for the oil to "go", as long as you keep the oil level topped up properly, and keep your dipper tray in, you should have no problem.
I built a strong Model B engine with Miller OHV head, Dan Price pump, drilled crank, and ran it at 50psi with an adjustable blow-off valve. Had real headache with oil pressure cutting out on bends, specially when cold. I had tried to get clever with swinging doors and baffles. An oldtimer persuaded me to put dipper tray back in with a half inch hole drilled in each dipper groove for oil drain-back, and I never had another problem.
IMO the extra volume pumps will pump alot of oil out of the pan on start up, specially when cold, and the oil sits up in the block. Why do you wait an minute to check the dip stick when you ve just run the engine?
So oil level must be kept up to the top mark!
Tom.
 
The drop in pressure was noticed mostly when the car had been run for over 1/2 hour and was totally warmed up. As mentioned before, there were 1/2" holes around the tray.
The notch around the oil pump opening was for the pressure relief valve on the Stipe pump
 

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bettlesr said:
The drop in pressure was noticed mostly when the car had been run for over 1/2 hour and was totally warmed up. As mentioned before, there were 1/2" holes around the tray.
The notch around the oil pump opening was for the pressure relief valve on the Stipe pump
Click to expand...

Hey Dick,
Hm, thanks for this picture. Those 'holes' are not what I was talking when mentioned previously. One inch holes in 'bottom' of each dip area is what I was saying. That drops all oil quickly to bottom as opposed to what is there. It worked for me on the present B in my '30 with stipe pump. Unless I'm missing something, do not see how those small holes in those locations...will help.
 
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hardtimes:
As I had the problem with them there, NO, they didn't help.
The original pan on my old engine had 1/4" holes in the dipper area with a stock oiling system. They really didn't help. Got about 5 highway miles before the babbit parted company with the rods and mains. Should have dropped the pan before we ran it on the street! Interesting thing, when I put it back together, I used plastigauge to check the clearances and found the plastigauge had dented the babbit more then the plastigauge was squished. I guess it was a soft alloy. That engine had been rebuilt pre-1950. Last registration was 1952.
 
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