crunch these numbers please

[Reg]

Hi everyone!

I took my car out for a ride tonite and took some notes in which I'd like opinions on.

This evening was beautiful and clear, about 6C

Ok at 70 mph in 5th, I was cruising at 3400 rpm riding on 205 60 15 tires on 15 x 6 fuchs. My oil temperature needle was riding on the top edge of 180 (so I am guessing 190) while the pressure guage needle sat just on top of the 60 mark.

My oil level guage seems to jump on acceleration which I guess is normal but at this speed it was riding at half way , 6 L. When the car is cold, the needle is at the lower level of the normal readings on the guage.

At idle (1100 rpm) the oil pressure drops to 20, temp. needle goes down to just under the 180 mark, and the oil level rises to between 7 and 8.

I know my idle is a tad high, but my hand throttle is broken and the car is not the easiest to start, and i do not want to be embarrased at a traffic light just yet!


One of the reasons I am asking is my oil light (the white light in the oil temp and pressure guage) is stuck on at all times! It dims and brightens at times as well and I am wondering whats up there. Also , the pressure guage was irratic in the fall sometimes riding way up at the top, just after changing the oil and not adding too much or too little oil.


Basically, are these numbers considered OK and within range of what a solid engine should be?

thanks for reading.

Reg

[jluetjen]

Reg;
You've got a lot of good data, the tricks is to just "decompose" it a little so that we understand exactly what it is saying.

First the Oil Level; this guage is only meaningful when the engine and oil are warm and the car is idling at the appropriate speed. At other times the data is meaningless since the oil is being pumped all over the engine and cooling system rather then sitting in the tank where the sender is. Unfortunately, you did not include what the oil level guage is reading under warm idle conditions, so I doubt anyone will be able to tell you anything about it. Since your idle is at 1100 RPM, I doubt that you're guage will ever be meaningful until you get the car to idle correctly.

I don't think that 180-190 degrees is out of line for the engine when the car is running at 70 mph. 911 engines are happiest when the oil is between 180 F to 220 F. If you were running near or above 220, the recommendation would be to upgrade your oil cooling system.

If you car is running about 60 (4 bar) psi of oil pressure when warm and less then 100-130 psi (7-9 bar), then that should be OK too. BA recommends the rule of thumb that a 911 at normal (warmed up) operating temperature should have 10 - 15 lbs (.6 - 1 bar) of oil pressure for every 1000 RPM of rev's. It doesn't sound like your car is violating that rule either.

As far as the white light on your dash board (2nd guage from left, top idiot light), I >>>think<<< that this is the brake light. Unfortunately I don't have an owners manual for my car, but according to my wiring diagram, that light is hooked up to the parking brake and brake system sensor. The ergonomics of that particular light are not great. Can someone with first-hand information confirm if I got this right?

[Reg]

Thanks John.

I know my wording could be clearer! sorry bout that one.

"At idle (1100 rpm) the oil pressure drops to 20, temp. needle goes down to just under the 180 mark, and the oil level rises to between 7 and 8. "

..so my oil level guage rides at or slightly above 7 when its at 1100 rpm. I should only take any reading from that as somewhat accurate when the car is idling and warm, and forget about it while the car is moving.

At one point last fall, my pressure guage went irratically high. I think it was a guage issue as the movement of the guage was normal , but it seemed as if the face of guage moved.

I have only driven some 600 miles in the car, so I have little experience with her.

Thanks!

[gregk1]

I have a 76s and my numbers are the same as yours but at idle about 750 on the tac oil pressure is less than yours maby 10. soon as you tuch the gas it jumps up right away And never had a problem They say as far as the tank level go with what your dip stick says not what the tank level says.And have the stick level at between min and max.My 74 didn't have a tank level so the stick is all I had to go with. These cars are SO much fun to drive It realy grabs you once you get in one and get the feel. I got my first one a little over two years ago and I have am on #nine now and still have six rather a NUT!! when it come to cars I guess So have fun and DRIVE ON!!!!