Low Oil Pressure

Bligaderski

Bligaderski

New Member
Jul 18, 2007
28
0
0
Tennessee
#1
I have an 89 LX the issue I am having is with oil pressure when warmed up. My Pressure is at 43 to 50 psi when started then when warmed up it goes down to 10 to 12 psi when stopped and 18 to 20 when moving. After a 25 mile drive the pressure stays lower than 18 and when i stop it goes down to 9-10 psi. I have an auto meter gauge and have checked to make sure the gauge is good. Does this sound like an oil pump problem or is it worse?
 
#2
Engine is usually nearing the end of it's career with what you describe.
Could be the heads, i wouldn't hold my breath though.
Doubt it's the oil pump.

Sounds like the bearings are probably done


How many miles are we talking about? If mileage is high, the engine really isn't worth any type of major surgery.
 
#3
Probably time for a rebuild. Sounds like typical bearing wear. For what it's worth, you can still run a very long time with oil pressure like that. The general rule is to have 10 psi of oil pressure for every 1,000 RPM. What weight of oil do you currently run?
 
#4
Ya, i drove mine with 7-12 at idle for like 2 years. Although it ate up about a quart every 400 miles.

But as soon as you know for sure, start considering what you are going to do, so when the engine lets go, and it will, you aren't caught with your pants down financially.

Get a magnetic oil plug, if when you change your oil and you see metal, you know you are in trouble.
 
#5
The car only has about 120,000 on it. I had a problem with a tapping noise on the top end, pulled the valve covers and ck the roller rockers i have for issues or if they are loose. It taps when its cold and stops when it warms up. I just pulled the upper and lower intake and replaced the lifters two weeks ago thinking that they were the problem it did fix it till this morning (its cold here below 30) and now the tap is coming from the other side of the motor (I kept the rockers on the same valves the came off from and I ck the push rods for issues) I cant figure out what’s causing the tapping, i have a set of 1.6 roller rockers and a trick flow stage 1 cam. Any idea if these are connected or what the tapping is caused by besides lifters?:shrug:
 
#6
For some reason people like to think lifters are a problem on these cars, it's really very rare.

Did you shim the 1.6 rockers? If so did you use the right size shims?

What heads are on the car? If they are stock, i'm sure the stock valve springs aren't thrilled with the cam.

How bad is the tapping? With the hood open and your head in there, it's gonna do some tapping for sure.
 
#7
These are on the pedestal mount so there are no shims. The stock heads are on the car, its tapping loud enough to hear in the car and out with the hood closed. I does’ stop after a few minuets running and there is no sign of it even with the valve covers off listening to each valve. If you let it sit and get completly cold it will do it again and you can hear which side of the motor its coming from (pass Side)
 
#9
I understand the oil pressure issue, but what's causing the tapping, Ive never had a tapping that wasnt caused by a lifter or a rocker arm. The tapping moved from one side of the motor to the other after i replaced the lifters (i maintained rocker arms in the same place along with the pushrods) It also stopped for a few weeks after i replaced them. im stumped
 
#11
There is a tray that sits below the rocker arms and hold the two centered and a pedistil that has a curve for the center of the rocker to sit on that sits in the tray and a bolt with a allen wrench hole in it, there is know way to shim them, and if mine are tapping then you would need to lower the rocker not raise it. plus if you shimmed it, it would move it up and out of the track causing it to shift from side to side. not sure how you could shim them. The roller rockers and cam have been on the car for two years and the tapping just started a month ago. I dont have my factory rockers or i would put them back on just to see.
 
#14
Bligaderski said:
There is a tray that sits below the rocker arms and hold the two centered and a pedistil that has a curve for the center of the rocker to sit on that sits in the tray and a bolt with a allen wrench hole in it, there is know way to shim them, and if mine are tapping then you would need to lower the rocker not raise it. plus if you shimmed it, it would move it up and out of the track causing it to shift from side to side. not sure how you could shim them. The roller rockers and cam have been on the car for two years and the tapping just started a month ago. I dont have my factory rockers or i would put them back on just to see.
Click to expand...


incorrect. pedestal roller rockers require measurement and shimming. summit racing has the shims for like $10 or so. This is likely why you are tapping. Go to crane cams site, and download the instructions for adjusting these. Your setup is mostly stock right?? It's rare that you'd have to get a shorter pushrod..as you described above. It's nearly always the opposite....so pick up that shim kit.
 
#15
The only question I have to that is these have been on the car for two years and have never given me any problem before last month. It is relatively stock other that the cam (trick flow stage 1) GT40 upper and lower intake. This morning I started the car and the tapping began I popped the hood and listened, it sounded like all of the lifters were tapping coming from the valley/center of the motor and after a minuet it got quieter and then it sounded like it was just the pass side of the motor. I drove down the road about .5 miles and it stopped tapping. If the car sits longer than 4 hours it will tap when started if it only sits for a few hours it doesn’t tap. I know I have an oiling issue do you think this is a problem with the motor not keeping pre oiling pressure after sitting. Also when sitting or below 1800 rpm’s the oil pressure is about 9-10 psi on the gauge if I tach it up to 2500-4500 rpm’s it goes up to 18-22 psi. I have a tremac trans and 5th is putting me at 1800 at 65 mph so my driving oil pressure is about 9-10.
 
#16
This is just an uneducated guess, but with oil pressure that low, maybe your lifters aren't able to stay pumped up fully, creating a little slack in your valvetrain and making some noise? If it's not making 20 psi at 1800 rpm, its' days sound like they are numbered anyway.

Was the oil pressure that low before the cam swap? Occassionally, guys will lose oil pressure when installing a new cam, and not having fresh cam bearings.
 
#18
Maybe I missed it but how are you checking your oil pressure?

For reference my 1988 had oil pressure like yours, as it is not my daily driver I tore it down immediatley and every cam/rod/main bearing was shot, completely brass looking. I doubted my guage and borrowed a good tester to make sure I was getting a good reading.

Same motor after a good rebuild has @100 miles on it now, 65-70 cold, 50+ at idle fully warmed up.

Matt
 
#19
The oil pressure mentioned above (50+ at hot idle) is VERY high. People seem to have this conception that more is better. But i think ford specs minimum idle oil pressure at 10psi.

To the original poster....i would say your problem is normal of high mileage 5 oh's that have been beaten. I would start saving some cash for a rebuild...or start scouring the junk yards for an explorer motor, or low mileage 5.0 bottom end.
 
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