Porsche 911S 1977 overheating

I have been having problems with my oil level meter. I am unsure if I have too much oil or too little. Yesterday after I added 1 liter, the car started to overheat. I had never seen it go over 210 F. I stopped when it hit 250 F. I got it home by making frequent stops with the heater fan on. It was 25 C here in Finland, but the car has seen higher ambient temperature. It is a US/Cal model, so it has the front cooler. (Don't know if it was optional on the ROW Porsches)

I took it out of winter storage a few weeks ago. It backfired for the first time and it has been running lean ever since. After it warms up, if I release the gas pedal from over 3000 RPM, the engine stops. If I let it down slower, it idles as smoothly as usual and at exactly 900 RPM.

It had dropped some of its oil during storage. I am afraid of overfilling it. I've been adding 1-2 liters every week. When I drive it the station (engine over 170 F), the dip stick shows the min mark. After I add 1 liter and press the gas pedal for a few seconds, the dip stick shows no oil at all ??? After the second liter it shows the min mark again ??? When I leave the station or warm up the car, the level meter shows the red zone at first. When I accelerate it jumps to ½ and gradually exceeds 100% mark (which scares me). When I come to a traffic light, the meter stays at 100% until suddenly it drops to the upper red zone again.

My pressure meter is broken. I am assuming that the oil light is a too little oil pressure light. Therefore it would have warned it I have way too little oil. Right?

One last question. Is the official Porsche oil filter different than a generic filter of the same size? Does it have a different flow resistance or other properties? Or is it just a higher quality filter with small performance advantages?

Jippii, Summer is here! Porsche_beginner

Reply to
porsche_beginner
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the first thing that comes to mind is the oil pump.

Reply to
woody

First of all: The only way to use the oil tank gauge is:

Warm the car up and park on level ground. Let it idle for at least 30 sec. Check the oil on the dipstick. It's OK anywhere between the marks. On the '77...seems like it's @ 1.25 US quarts between marks. The inside meter is only reasonably accurate under the same circumstances. The oil cannot be checked with the car in motion or when revving the motor.

Now...your other problems sound like something to do with the ignition system (plugs, etc) and/or the CIS injection...but unrelated to the oil problem. Also...when was the last valve adjustment. Every 15K miles is a must...more often if you drive a lot at high speed.

Hope this helps....

Reply to
Weekend Guru

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