RG5

A few questions RE the 1985 Carrera I got recently.

I have been seeing some fluctuation in the engine oil level guage whilst the car is being driven, usually at standstill returning to the full position.

Is this normal? It doesnt do it all the time but often there is fluctuation in the needle to varying degrees.

I also get some intermitten knocking/pulsing noise every second or so revolutions, mainly heard when the car is idling.

The car is having a full comprehensive service next week and this may be related to the valve clearances, which I think need adjusting.

Car runs very well with around 160-170 psi per cylinder on the compression test I had done during the ppi. Acceleration is smooth and regular with no hesitation or flat spots in the power delivery.

Apart from these "issues" its been fine. I kind of expect a few issues with a 20yr old car.

Richard.

RG5

I should add that the engine oil pressure level is OK, around 4500-5000 when around 3500-4000 rpm

pjc

Being a dry sump engine the oil is held in a tank under the right hand rear wing. The oil level gauge is measuring the amount of oil in that tank. At rest, engine off, the oil is mostly in the tank with some residing in the sump. At start up the pump takes out most of the oil from the tank to circulate around the engine - thus the gauge will be probably be reading zero. As the engine warms up the system settles down and under normal driving conditions the gauge will fluctuate from zero (under acceleration) to maximum (at idle or cruise with almost no throttle). Between these two extremes the gauge will move around a little as the pump calls for more or less oil, dependent largely on throttle use. Your gauge is behaving normally.

Remember also that the gauge is not the most reliable source of oil content - this remains the dip-stick - always check the oil level with the engine at working temperature and on level ground. The difference between max and min on the gauge is about 1.5 to 2.0 ltrs so if you decide at some stage to do your own oil change be aware of this, also resist putting too much in to begin with; it is easy to overfill these engines.

PJC

jet911

I would not worry too much about the oil level gauge. The process works as PJC stated. The other thing to remember, everything must be checked when the car is warm at running temp. When the car is cold, the oil has not heated up and expanded and will registar low on the gauge. The only time I even look at the oil level gauge is when I've come to a stop when the car has warmed up. Then, the guage should read about the middle, but as soon as you take off, the gauge will drop to zero. Use the gauge as an indicator. The true measure is when the car is warmed up and on level ground, then you check the dip stick with the car running, the oil should be about halfway between the uppper and lower marks. A common error is to start adding oil when the car is not warmed up, then you have a mess....