924Board.org

patrick_924 · Joined: 22 Feb 2006 Posts: 7 Location: Newcastle UK

my otherwise superb 924 has (i think developed a fault). when i start the car the oil pressure gauge instantly reads 5 and then during the first few miles driving moves up to 6-7 and 5 at idle. when warm ( 10 mins or so of driving) idle drops to 3 bar and running at 4000 rpm about 5 bar.
Previosuly on start up and idle oil pressure read 2 and 5 bar whilst running at 4000 rpm. i dont want to cause any damage to my 924 which by the way is a uk spec 2.0 n/a
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1984 924 (Daily driver for 4 years)
1972 beetle 1302s (under construction!)

zwoodward · Joined: 07 Mar 2006 Posts: 58

Others will have to correct me if I'm wrong but I believe I read on this board that the spec for oil pressure is 6-8 bar at 2000 rpm

zwoodward · Joined: 07 Mar 2006 Posts: 58

I just checked my Hayne's manual and it says 5-7 bar at 2000 rpm with the engine warm

gohim · Joined: 02 Nov 2002 Posts: 4459 Location: Rialto, CA

Could be a problem with the oil pressure sensor, could be plugged holes in the camshaft oil supply tube, or could be the result of dirty oil, or a bad ground wire.

When I first got my 81 924, I suspect that the PO (previous owner did not change the oil as often as required based on the condition of the car. The oil pressure gauge would pin the needle on the high side when the engine was cold, and later drop down and work normally. I attributed this to a dirty oil pressure sensor. About two-three years later after numerous oil changes, the oil pressure guage stopped hammering the stop when the engine was cold, and has worked normally since then.

I suggest that you start with an oil change, if it has not been done recently. If the oil was changed recently, is that when you noticed the problem? If so, was the same oil filter used that you normally install? That could be your problem. How often do you change the oil. Many people have gone to ridiculously long change cycles, maybe your oil pressure sender/sensor is clogged up as mine was.

The cylinder head has a tube that runs along the top which is plugged into an oil gallery in the cylinder. This tube is used to supply lubricating oil to each of the eight lobes of the camshaft. Dirty buildup from dirty oil or debris not caught by the oil filter can close off these holes, and starve the camshaft lobes of oil, leading to accellerated camshaft and lifter wear and damage. A symptom of this problem would be increased oil pressure. The plastic elbow that connects the oil supply tube to the cylinder head ages, and shrinks, and sometimes breaks causing a drop in oil pressure. Either of these problems is a critical issue that needs to be attended to immediately to avoid costly damage to the engine.

I suggest that you remove the valve cover, remove the oil supply tube, clean and inspect it throughly (make sure all the holes are clean and clear (do not enlarge them) and the tube is not cracking (carefully check around the mounting brackets), then replace the plastic elbow (they only cost about $1), and adjust your valve clearances while you are in there.

patrick_924 · Joined: 22 Feb 2006 Posts: 7 Location: Newcastle UK

i change the oil about every 3 months or 5000 miles usually about the same. same type of oil and filter is always used. the problem began before the last oil change a few weeks ago. i shall follow your guide over the weekend and see what happens. Many thanks
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1984 924 (Daily driver for 4 years)
1972 beetle 1302s (under construction!)

seanski44 · Joined: 13 Mar 2006 Posts: 532 Location: Nottingham UK

gohim · Joined: 02 Nov 2002 Posts: 4459 Location: Rialto, CA

I don't know anything about the plastic elbow being discontinued.

This is a critical part of the oil supply system.

If the elbow is brittle or shunk and leaks, then it is not reusable. There is no way to repair this part, and your car should be parked unitl you can locate a new replacement part. I bought a bag full 15-20 years ago for less than $1 each, and replace the elbow on the car every time I adjust the valves. Recently, I bought another small quantity at the Pomona Fairgrounds Porsche/Corvette Swapmeet for less than $.25 each.

If your local Porsche Dealer, or Porsche in Germany has decided to not make this part available anymore you can always try to get them from Audi (who actually made the engine). If they are still available from Audi, and they are infact discontinued by Porsche, then it would make sense to buy a dozen just to ensure that you will have them when you need them for your car.

seanski44 · Joined: 13 Mar 2006 Posts: 532 Location: Nottingham UK

Dans931 · Joined: 20 Jan 2006 Posts: 45 Location: Baltimore

These oil gauges aren't always precise, especially after 25 years or so. Mine always read less when the lights were on. The gauge and sensor are all VW parts. With a warm engine at 200,000 miles, I had 3 bar at idle and 5 bar at 3,000 rpm.

Daniel

patrick_924 · Joined: 22 Feb 2006 Posts: 7 Location: Newcastle UK

well as promised i took the rocker cover off and adjusted my tappets whilst looking for any issues, all was well the small plastic elbow looked fine and the holes in the oil supply tube were also clear. the engine does not use any oil etc so i will ignore the gauge and continue to enjoy my car!!
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1984 924 (Daily driver for 4 years)
1972 beetle 1302s (under construction!)