ok,, I'm assuming coutangman is talking at a idle. Not sure how much he warmed the car up when it was still at 75lbs. 50 degrees and oil gets warm, if he has 75lbs at idle, yea I think it's a problem. Hopefully gauge, but it's his call. Sorta need more info
38 pounds hot at idle isn't the worst thing in the world. Sounds like someone put a high flow/ high pressure pump on there for no good reason. All those pumps normally are is a stocker with a heavy bypass spring. The modular enigne is a constant flow pump with no HP bypass, and will easily see 90 psi cold at idle. Just remember this one rule and you'll be golden. Pressure is the restriction to flow. Some bad parts of running excessively high pressure are: 1) Oil leaks (blown out seals) 2) Oil pump wear (running more power through the pump) 3) Extra parasitic power loss (using more power to turn the pump) 4) blockage in the oil system (could cause high pressure)
Sounds like the pressure relief valve is stuck. I`d run it and let it warm up completely,shut it off and let it cool completely. Do this a few times and more than likely it will work loose. Also do NOT use a Fram filter. Cut one open sometime and you`ll see why. 15-30lbs,at idle--- 45-65lbs,at 2000-3000rpm,totally warmed up is average for a stock 302 in the 70s era. It doesn`t sound like you have a major issue. I would only worry if after running around awhile,the oil filter starts to bulge. They actually have been known to split open,or worse,blow completely off. Good Luck with it,I believe you`ll be just fine!
I bet someone replace the pump with a heavy duty/high volume pump. I'm using a HD/HV pump...that is why I have high oil pressure. That is way to low with cold oil...even with hot oil it is still too low. The oil pump has a by-pass built in so it won't get over a certin amount of pressure before it bleeds off. About the only way to push oil out of the seals is a defected PCV not allowing the engine to breath. With 8 lbs of pressure the bearings are shot or the cam bearings have rolled over to block the oil passage...or defected gauge or sending unit if you have an electric gauge giving false reading. A regular stock oil pump should pump at 30-35 lbs.
Wow, let's tear scooper a new one I have always heard 10 psi for every 1000 rpms, as mentioned above. If true, then 8 psi at idle should follow those rules, but I have never seen it drop below around 20 at idle. Then 40-50 at cruising speeds. Anyway, I was saying 8 at idle was closer to normal than 80, not that 8 was correct.
Is that true, about it being a Chevy rule of thumb? Apparently I am not the only one to adhere to that rule, as many on here have stated it, and that is where I learned it. I would like to know what is true for Fords. Or IS there even a rule of thumb for Fords?
Ford 1970 manual says at 2,000 rpm oil-hot pressure should be 35-60lbs. When I was a diesel mechanic, early 80's they started to worry on fuel usage. Detroit Diesel cut their oil pressure down to save fuel. All our drivers complained,,, low oil pressure. DD rep came around an held meetings with the drivers and said ,, 10lb per 1,000 rpm. Who else spec's this I'm not sure. Back at the ranch,, coutangman may have a problem. Not sure if pressure was this way (sorta thinking no or this would never come up) Gauge would be first thing I check. Engine needs warmed up, (ever see a oil temp gauge, amazing how slow it warms up compared to water temp) pressure should be checked then with a known gauge and we'll know more then. I've had relief valves stick,,,, aint a pretty sight, but I was lucky on no engine damage
It's a physics thing. That is the oil pressure required to pump oil up the con rod to the wrist pin and overcome the force on the oil generated by the upward movement of the con rod. As far as I know both the Ford and Chevy pump use the exact same design.
80 isnt high if its cold heavy oil. Its should come down hot and I'm sure it will. Even a Standard Fram filter is rated to 250 pound burst pressure. The cheapy filters I have seen blow out with 100psi though. Pennzoil filters up here are very thin and cheap. Walmart uses them. Our Mopar filters take about 130 pounds to bulge them. Never seen one blow even with a bad pump running 140psi.
my maverick has a 302 that is wore out. It does have a new oil pump in it. I run 10w-40 in it. It will have arund 60 psi when it first cranks up, around 20-25 at hot idle and around 40-45 driving normally
My 18 year old motor in my stallion runs 60-70 when I start it. Once warm it stays in the 50-60 range. I wont get into what oil I run as not to derail the thread. My thinking is you are in fine shape.
