too much oil pressure - 2 liter

J

Joe Craven

New member
I just put my motor together again, new oil pump, bearings, reground crank etc. It's a Pinto 2 liter style SOHC motor and it's in my 71 ITB Capri.

I have 60psi oil pressure at idle and over 100psi when really revved with a warm motor. Bearings are properly clearanced, .002 to .0025 mains and rods. It sounds like the pressure relief valve on the oil pump is stuck and I just do not want to take this motor apart again. I've put in 10-30 oil and I'll see if the pressures come down.

Anybody have any easy ideas? I've been having too much oil pressure for some time with this setup but with the new oil pump, it is much worse. If I enlarge the oil holes for the spray bar that oils the OHC, will that lower my pressures but create too much oil to the top end?
 
I always had the opposite problem with the two liter Ford. My clearances were a little larger than yours, however, about 0.003in. My pressure was about 80 psi cold, then about 35-45 psi hot. I always ran that way, and reved to about 8500RPM. I never lost a motor with this setup. Incidentally, the motor was for a BS car of the '70's. Contrary to your thoughts, I RESTRICTED the oil spray bar with a drilled socket set screw. Philosophy was that the original spray bar was intended for adaquate supply at idle...I was way beyond that. This restriction was intended to leave as much oil in the pan as possible. Remember, that the return drains of the head in the two liter are barely adaquate (two). I ran a stock pump ('70s), shimmed relief spring, baffled stock pan.

Stock engines were known for having a swimming pool of oil in the cover at speed.

I never lost a motor, and with careful startup proceedures, never lost a racing cam. Compression was in the 10.75 to one range with flat top pistons, reduced waterpump speed (Capri pulleys), DCOE45. Webers.

Good racing.

Bill
 
Joe!
What ever you do, don't put more oil in to the valve cover. I ran a B/S (GT-3) Pinto for 20 years at 60 psi hot and never had any trouble. It sounds like the bearing on the shaft that runs the oil pump and distributor is turned wrong and the oil hole is not open. Pull the shaft out and use a bent wire to poke into the oil hole to see if its lined up. As for as more oil to the valve cover, well I once had the spray bar break its mounting tab and then the oil pressure would push the spray bar away from the head. Filled the valve cover and puke tank up with oil. My dash mounted red lite got me stoped before I hurt anything.Thats what too much oil can do. Red lites are great items to have.Hope this helps. DICK
 
Thanks guys, I'll leave the head oiling alone. My last motor ran about 45psi hot, ran great for two years before excessive blowby due to ring wear.

Dick, I think I installed the bearing you described myself.... I'll look tonight, hope I installed it wrong!

Thanks -Joe
 
Bearing is installed correctly. I took the car to the track today, refilled it with 3 quarts 10-30 and 2 quarts 5-50 Castrol Synthetic oil since that is what I had.

Cold oil pressure ~80psi
oil pressure spiked a bit over 100psi but I kept the revs down on the first lap.

At about the 25 minute point, oil pressure was 80 to 90psi. Odd thing is that the pressure fluctuated when the revs got over 6500rpm (I was pulling 7000 in 4th on the two straights) with the pressure measuring 82, 84psi etc.I'm not sure if it was the vibration or oil foaming? I run a baffled pan with a crankshaft scraper which should help keep oil in the pan. Any ideas?

Hot oil pressure @ 1000rpm idle was about 38psi.
Joe

[This message has been edited by Joe Craven (edited March 16, 2004).]
 
Joe!
I had nearly the same thing happen with a 427 in a cobra 35 years ago. I never did find what was wrong. It just started doing this after the engine had many hours on it. I finaly took out the hi-po oil pump that Ford said to run and replaced it with a plane-jane 390 pump. Fixed it on the spot. You just never know. You should have no more than 10 psi per 1000 rpm. I always like to be on the low side of this. If it starts putting oil into the puke tank, you better drop the pan.Low oil pressure is safer than very hi pressure.
 
Joe On the 2.3l it runs about 48psi max and when warm it runs 35-40psi all day long> We run a Meling hi volume pump and 20w50 Valvoline oil. Later Glenn
 
Thanks guys, I've been thinking and I suspect that the motor is starving for oil at the end of the long straights due to the excessive pressure which is forcing too much oil into the valve cover. I'm going to install my trusty old Ford OEM pump which was in the motor before.
 
Joe!
One thing I always do is to run a no bypass filter on all the fords I build. I use the AC Chev racing filter. Jerry Walsh once told me he has run for hours at Daytona with no more than 35 psi of oil presure in a 2.3L. Too much presure cost you HP too.With a stock ford filter of any kind, the bypass is always opening and closeing, so what good is more presure? DICK
 
JOE,

My 2.3l ran 45-60 lbs cold at idle and 65-70 lbs hot 3000 rpm and above. No drop in pressure after the long straight at Thunderhill. My motor has about 40 weekends on it.

Barry
 
You do not need a hi-volume pump for a 2.0 Ford. I used to use them in IMSA and one of the Mellings hi-volume pumps started breaking bypass springs which let a lot of oil bypass. With the oil bypassing it heated the oil by an extra 100 degrees real fast. That told me that you should use a pump that has the volume to give you about 10 lbs. of pressure per 1000 rpms at speed and no more. Any excess oil pump volume has to be bled off and that just uses up horsepower and makes oil temp.
I have run these engines with as little as 35-40 lbs. at 7,000 rpm with no problems. Usually tried for 60 lbs. at 7,000
 
Joe!
One other idea came to mind, was I once used so much moly on a new cam in my 2.0 that the filter pluged up and the oil pressure and oil temp went sky high. Lucky I saw it at once and got it fixed. Thats what happens when your in a hurry to go race. Just another idea. DICK
 
I made it through the season opener @ Infineon, got a 3rd place with a close battle for 2nd with a 2002. I was less than a second from the lap record and beat my best by almost a second. I ran an old Ford pump that is worn beyond specs but was able to build pressure to 50psi.

I checked my oil and it appears to have flakes of bearing material in it. I'm going to pull my motor and I expect to find damaged rod bearings.

My question is what do I have to do to fix my new oil pump. I'm pretty sure it is the bypass valve but I don't see an easy way to get to it or replace it. I see what appears to be a staked cover which might have the spring behind it. If that is the cover, what do I do to look at or replace or ..?

Thanks guys.
 
JOE!
On my old GT-3 Pinto, I ran both the stock pump and the hi-vol pump with very little difference in oil pressure. 60 psi max both ways with 20/50 dino oil. What did make a difference was useing a #8 size breather to both the valve cover and the block below the intake. I also used #10 AN lines to the remolt oil filter (AC Chev Racing) and oil cooler. NEVER had any bearing trouble period!!!! Use to change them just because the motor was apart. They always looked good and re-useable. Chev filters with a Moroso adapter worked great. I even used a stock oil pan with no problems. RPM was always 7000/8000 range with either stock or roller rockers. Take a look at what oil your useing. Vavoline 20/50 Racing was what I used in those days. Hope some of this helps. DICK
 
Redline 30wt racing oil.

I took apart the new pump and compared to an old one. It is about 25 to 30% longer so it must be a high volume Melling unit. The pressure relief valve seems free and I think it was working fine. It might have moved, but the high volume pump overcame the relief bleed off and built the high pressures regardless. I have a standard size pump from my used parts pile that looks to be in good shape.

I'm planning to install a Moroso exhaust connected crankcase evacuation system in case blowby is keeping the oil in the top of the head. Any thoughts on these to keep a vacuum in the crankcase?
 
You may want to read section 17.26 (think its the same for 2004) in the GCR before hooking your engine breather into the exhaust system. This seems to prohibit what you want to do.
 
John--We are spoiling his fun...

You can get the same giggles with a replumped stock emissions air pump
evacuating your crankcase into the dump tank, except it weighs more than the prohibited exhaust check valve system.
 
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