So I was just out to my lunch break and my oil pressure dropped. On the way to work this morning everything seemed fine but I can't guarantee that I looked at the oil psi this morning.

When I looked at it at lunch the psi was about 12 to 13 normal running is around 25 to 30 psi. Nothing has changed except yesterday I started having funny electric issues. My windows would only role down not up and my radio went out any ideas would help

 

My 65 390ci with 35000 miles is in being "reborn" and had the same symptoms. Looks like the cam that was used on the rebuild is now flat on one lobe. All those metal filings were swirling around inside. No loss of power but some loss of fuel mileage. I only noticed that when I came to a stop the oil pressure slowly went down to 10 lbs or less. Then back up to 40-50 on the highway. Looks like it will only cost $1800-2000 by the time I am finished with the machine shop. Hope yours is a cheaper and easier fix.

 

well I am wondering if it can be an electrical issue. So when I got home from work today the gauge was reading normal and my radio and windows where working. I need to re do the wiring anyways so maybe I will just do it soon than later to see if that fixes the problem.

Isn't there a manual way to check the pressure to see if its a faulty gauge. The engine has less than 20 k on it thats been cruising nothing extream at all.

 

These engines as with many will lose oil pressure a bit during idle when at operating temp...Mine drops to about 15 or so and the alt light flickers a bit...crack the throttle and all is well...if the oil pressure kicks back up immediately and the oil is clean I wouldnt think much of it...The electrical is a result of the alternator not spinning fast enough to kick out the juice needed for accessories...headlights dim too at night at idle..It is putting everything its making at those lower speeds into the battery to keep it happy...so to speak...
As to the engine noise...If the noise is consistent regardless of hot or cold or idling or at normal operating RPMs, you could have a dead lifter as they used hydraulics and low oil pressure at idle could be starving them a bit possibly. Lifter ticks arent uncommon...mine has a lazy tick that takes a bit to disappear...lazy lifter as the engine has been gone through once. If you are familiar with Chevrolet small blocks they are notorious for losing lobes...a flat cam is blatantly obvious...and is loud and the engine wont run worth beans...coughing bucking sputtering...and popping through the carb are all possible...I had a van with a flat cam....once upon a time...my 2nd venture with bowties...
One thing you could do if you suspect major engine component failure in the process of failing or already done is change the oil...use a nice clean pan and when its empty see if theres any kind of shiny metal flecks in the mix. You can also open up the filter in a clean pan also and see what, if any metal stuff is in there..or anything else that shouldnt be. A good quality filter is a great investment...WIX is good as it Motorcraft....


- cs65

 

You can pick up a manual oil pressure gauge and tubing at most auto parts stores and hook it up just to see what pressure you ''Really'' have? I have a manual pressure gauge
in my 65'' just don't trust the electric ones!...$10 bucks and piece of mind, lol...

 

I think I am going to go for the manuel one. I started the old truck last night and let it idle for a while and then drove it around the pressure was fine and so I decided to drive him to work this morning and all seems fine. I think the rough idle yesterday was do to human error. I think I pushed the chock in too far it was cold and I was in a hurry so I started the truck then went back inside for a bit to finish a few things. Who knows I will chang the oil to be on the safe side but I just changed it a few hundred miles ago. One day I swear I am just going to take a BFH to him. lol

 

All three of my trucks oil pressure drops at idle when they are warmed up. When they are cold with 10/30 oil they make upwards of 60 psi until the engine gets to around 100 degrees.When warm it will drop down to 10-15 at idle, 40-45 at driving speed. Many things can make a tick,lifters and fuel pumps are a few of the many along with exhaust leaks and headers. I almost tore apart the 390 in my 64 F-250 thinking I had a rod going away. It ended up being the fuel pump ticking loudly.
When it's cold and dark we're running our heater at full blast,driving with the lights on, the alt is being asked to do alot keeping up with all the elect. demand. So check and clean the battey post, the alt belt snug ( If you can turn the pulley by hand even a little you need to tighten the belt) and just as insurance make sure the nuts on the back side of the alt are snug too , just don't wrench hard and break them. When it gets cold all kinds of things that were fine and tight in warm weather seem to loosen up and cause gremlins to pop up

 

Back in the day when gas was gas and not mixed with other stuff. 110 octane was still avialable. I used to run my 352 with a summer and winter idle. In the winter after the truck has run and warmed up so it will maintain idle without the choke turn on all of the electrical equipment and then set your idle. Helps the alt keep up with the demand being placed on the battery in cold snowy and rainy weather. It may idle a little high on nice days but they are few and far between. At least on the east side of the mountains in Washington state. Then when summer rolls around and more daylight so less headlights and heater wipers are needed set the idle back.

 

jagergirll, Your oil pressure is OK. Don't fret over it, sounds pretty normal to me. It is more important with a FE to keep oil in it over the pressure it is running.

You might have a minor electrical issue.





John

 

Jowilker I think I am going to agree with you. I think if the pressure was low do to bad cams or lifters there would be noise and it would run rough. My alternator is dieing I checked it out last night and when I have heater lights and the radio on the volts on the battery are about 12.3 ish less than when the truck is turned off so I am re wiring "gramps" and I will change the alternator hopefully that will fix my electrical issues so my windows will role up not just down

 

jagergirll''
When your light's, radio, heater is on and you have 12.03 volts when running'' that is a
good sign that your Alt is working!..as long as you don't drop below 12 volts with all your
acc' on then your OK!..as far as the oil pressure gauge? I use a standard manual gauge!
Just ask for one at your local parts store!, they sometimes have the volts, oil, and temp
gauges all in one but you can get just the (oil pressure Gauge) by it's self! check out Jeg's online' they will have it if your parts store does not..

 

wow 12.3 volts seems low for just a couple things being on. My car jumps up a lot when its on.

 

I use a idiot light and a manual guage. I had a oil pump sieze on a 58 with a 352 and it had a idiot light but I knew right away I had no oil pressure. a simple tee fitting is all it takes to use both. Tom

 

I am concerned with my oil pressure, just rebuilt my 390, I have about 125 miles on it now, idle oil pressure is 25-30 psi, cruising 45-49psi, I am happy with this. My concern is at operating temp at a long light, psi drops to 4-10psi. I am using the factory guages psi reads just above low range normal. also using aftermarket autometer guage wich is the 4-10psi. Has no abnormal noises, runs great!!
Any ideas suggestions? going to change oil and filter when cllse to 200miles
thanks

 

Change you oil and filter as if you have used assembly lube ( I hope) it will restrict some passages and your filter as will all the metal that ends up in your oil pan after a new engine is run for its first 100 miles. Change your oil again after 1000 miles. At idle my trucks drop down around 10-15 psi at operating temp and run between 45/50 psi at cruising rpm