Changing out an oil pump
- Thread starter thechori
- Start date
most likely excessive wear on crank and bearings, not the oil pump if it is infact low.
What is your oil pressure @ idle?
What is it @ and above 3000RPM?
Also, what type of gauge are you using to check the pressure?
What is your oil pressure @ idle?
What is it @ and above 3000RPM?
Also, what type of gauge are you using to check the pressure?
-from memory, the pressure is maybe around 1/5-1/4 line on the gaugecjsupra90 said:
-i don't recall the oil pressure ever changing when driving.. could this mean that the gauge is just bad?
-i havent CHECKED the pressure myself, i had someone come by that wanted to buy the car and he said that i should change the pump b/c the pressure was low on the oil pressure gauge inside the car
First, I would fix that oil pressure gauge, get it working, then go from there. If it's still somewhat low, I'd say do an oil change yourself, I'd feel alot better doing it personally then having a gas station do it. Get a 5W-30 or 0W-30 motor oil, provides the best protection and you won't have too much oil pressure.
-Matt
-Matt
alright, i was wrong about the gauge not changing, i just never really noticed..
at idle the oil pressure is at 20 lbs/in^2, when i rev it up to about 3000 rpm, it gets up to around ~40 lbs/in^2, didn't wanna push it any further in my parking lot or i'd have complaining neighbors. but yea, i'm pretty sure it's not the sensor now
at idle the oil pressure is at 20 lbs/in^2, when i rev it up to about 3000 rpm, it gets up to around ~40 lbs/in^2, didn't wanna push it any further in my parking lot or i'd have complaining neighbors. but yea, i'm pretty sure it's not the sensor now
that pressure is perfectly normal. at idle, the gauge should read between 20/60 psi (from memory, owners manual) and driving it should be between 40 and 80 psi.
mine reads the exact same. trust your car, not someone who wants to buy it.
mine reads the exact same. trust your car, not someone who wants to buy it.
From the TRSM:
http://www.cygnusx1.net/supra/Library/TSRM/MK3/manual.aspx?Section=LU&Page=4
At operating temperature:
At Idle - 4.3 psi or more
At 3000 rpm - 36-71 psi
When the oil is cold, the gauge will show higher psi until it's warmed up; then it should fall into the above ranges. The Supra oil system is a low pressure, high volume system. Unless a mechanic is familar with the 7M, when he sees 5 psi at idle he will tell you it is low....it's really not
http://www.cygnusx1.net/supra/Library/TSRM/MK3/manual.aspx?Section=LU&Page=4
At operating temperature:
At Idle - 4.3 psi or more
At 3000 rpm - 36-71 psi
When the oil is cold, the gauge will show higher psi until it's warmed up; then it should fall into the above ranges. The Supra oil system is a low pressure, high volume system. Unless a mechanic is familar with the 7M, when he sees 5 psi at idle he will tell you it is low....it's really not
for further refrence whenever a "mechanic" tells you something, doesn't always mean their right, alot of mechanics rarely see supras and don't know alot about them, so don't always take them for granted. But if its anything to do with oil jdub is who you need to talk to...he'll never steer you wrong:icon_biggjdub said:From the TRSM:
http://www.cygnusx1.net/supra/Library/TSRM/MK3/manual.aspx?Section=LU&Page=4
At operating temperature:
At Idle - 4.3 psi or more
At 3000 rpm - 36-71 psi
When the oil is cold, the gauge will show higher psi until it's warmed up; then it should fall into the above ranges. The Supra oil system is a low pressure, high volume system. Unless a mechanic is familar with the 7M, when he sees 5 psi at idle he will tell you it is low....it's really not
^^^ and I would never use 0w-30 or 5w-30 oil in a 7M. Too thin. The bearing clearances in these engines are larger than the newer cars. 10w-30 or 10w-40 is the thinnest to use.
mrnickleye said:
No offense, but that is flat incorrect concerning oil viscosity
A 5W-30 is not thin as compared to 10W-30...at operating temps, the viscosity is the same assuming the same manufacturer, syn vs. mineral, and basestock. Let's take Valvoline for example...Durablend, a Group III basestock, synthetic blend oil:
http://www.valvoline.com/products/Durablend.pdf
Looking at this chart comparing 5W-30 to 10W-30 oil, the viscosity at 100 deg C (operating temp) for 5W-30 is 10.33 cSt, for 10W-30 it's 10.84 cSt...virtually identical. The difference is at 40 deg C; for 5W-30 the viscosity is 57.89 cSt, for 10W-30 it's 71.45 cSt...a significant difference.
This is the common fallacy people make when looking at oil...oil does not thicken when it gets warm. Instead, a 5W-? or 0W-? thickens less when it's cold. The upper number will tell you what the oil viscosity is at operating temperature...in this case a 30W. Both will behave as a 30W at engine operating temp and provide the same viscosity. The difference is viscosity when cold...the 5W-30 will flow better for that morning start, especially in colder climates. If the oil seems "thin" pouring it out of the bottle into your motor, that is a good thing if the grade meets the specs for your motor on the higher number.
You are half correct concerning bearing clearances. On a well used motor, a 10W-40 might be just what you need to keep oil pressure at TRSM specs. On a re-built motor, a 5W-30 is more appropriate to give you the pressure you need. More pressure is not necessarily a good thing.
One other point and I'll get off the soapbox. Make the same comparison I did above for the 30W oils for the 10W-40, 15W-40 and the 20W-50. Note the viscosity is a little higher at 100 deg C for all 3 oils, but the viscosity at 40 deg C is much higher than either 30W oil compared to the 40W oils and double for the 50W oil. That's why you'll never hear me recommend a ?W-50 oil...it's just too thick when cold to flow in your engine....that's also why pressure goes so high on a cold start with ?W-50 weight. IMO, a 10W-40 is the highest weight that should be used in a 7M and that's on a high mileage motor.
If you want a little more light reading, take a look at this thread x87supra87x started...a lot of info discussed in this one
http://www.supramania.com/forums/showthread.php?t=31789
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shoot, i noticed today that the pressure on the oil got REALLY low, around 5psi i think.. i'm not sure if it's b/c of the cold weather, or if it's been doin this the whole time (when the guy diagnosted it), but i'll be sure to keep an eye on the gauge.
when i'm out of gear and not on the gas, the car was idling around 10psi, still low.. not sure whats causing this and i don't really know what to do
EDIT
also, the car stalls out VERY easily when you don't give the car enough gas, could this be a result of the low oil pressure?
when i'm out of gear and not on the gas, the car was idling around 10psi, still low.. not sure whats causing this and i don't really know what to do
EDIT
also, the car stalls out VERY easily when you don't give the car enough gas, could this be a result of the low oil pressure?
thechori said:
car at idle cant drop below, 4.3 at idle, so your fine on idle...
at 3k should be around 36-71 psi if i remember right.
get a lil thicker oil if your worried about the oil pressure
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thechori said:
Ok - First of all, oil pressure will not cause the motor to stall. There are several things that can cause the motor to stall...pull the ECU codes before you do anything else. This page in the TRSM tells you how:
http://www.cygnusx1.net/supra/Library/TSRM/MK3/manual.aspx?Section=FI&Page=23
Second - please read what I posted above...post #12 and post #15. Your oil pressure is not low! (Assuming what you have told us is correct). You are saying oil pressure is between 5 and 10 psi at idle...that meets the TRSM spec.
To tell you more, I need these questions answered:
- Is the oil level as shown on the dipstick good? Half way up the marks or greater?
(this is the most important...you must have the correct amount of oil in this engine. A little high is better than it being low. You will lose the motor otherwise)
- What is the weight oil you are using? 10W-30, 10W-40, etc.
- What kind of filter?
- What is oil pressure at 3000 rpm?
- How many miles are on this motor?
A thicker weight oil may or may not be the answer...do not run a ?W-50 weight oil, especially in cold weather.
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alright, sorry but when i first stated my idle pressures, it was 20psi, so i thought that was the standard for the idle, then i was driving and i looked and saw the 5 psi was pretty shockedjdub said:
i ran a diagnostic a month ago (nothing in the car has changed since) and there were no codes, so the car is ok i guess, unless the supra in general is just easily stalled