[Main C900 Bulletin Board | BBFAQ | Prev by Date | Next by Date | Post Followup ] Member Login / Signup - Members see fewer ads. - Latest Member Gallery Photos Normal Like This Post: - Subscribe to Daily Digest for this Bulletin Board Posted by Ari [Email] (#2847) [Profile/Gallery] (more from Ari) on Wed, 19 Apr 2006 04:54:56 In Reply to: Dipstick, Jimmy from Mass, Tue, 18 Apr 2006 13:39:13 Alert me when someone posts in this thread: Members do not see ads below this line. - Help Keep This Site Online - Signup

The level is wrong because when the engine is running, the oil is being pumped around the engine - doing it's job. There is oil in the passages, it's pumping up the hydraulic lifters, and generally circulating. When the car is shut off, the oil drains down into the sump. That's why the car has to be off for a few minutes before you check the oil - the oil is still draining.

As to why it stalled - there is a hose from the valve cover to the intake manifold. This hose (with a PCV valve) sucks fumes from the crankcase and burns them. In the good old - pre-emissions days, they were just vented to the air. It has oil fumes, blow-by from rings, etc. Nasty stuff. Nowdays, all cars have some Positive Crankcase Ventilation (PCV) systems. The crankcase normally runs at a slight vacuum, being sucked on by the intake. When you pull out the dipstick, you probably heard a whistling sound. That's the sound of air being sucked in through the dipstick, into the crankcase, up through the oil passages, out the valve cover, and into the intake manifold.

OK, so why does the car stall? You just opened up a massive vacuum leak. A whole bunch of air is getting into the intake that did NOT go through the AMM. This is un-measured air the fuel control doesn't know about, so it doesn't add any fuel. The fuel-air mixture goes way lean, and the engine stalls.

That's why the gasket on the oil cap is important to keeping the engine running well. This is true of any car - even on an engine with a separate dipstick/ oil filler cap will do the same if you pull out the dipstick.

posted by 192.249....

• Dipstick, Jimmy from Mass, Tue, 18 Apr 2006 13:39:13
  • Normal, Ari , Wed, 19 Apr 2006 04:54:56 <-- Viewing This Message
    • 16 valve engine will still be running, Andrey, Wed, 19 Apr 2006 06:26:51
  • You can't get an accurate level with engine running, 72saabsonett , Tue, 18 Apr 2006 17:24:26
  • Yep - this is a Classic 900 quirk, Jonathan Scupin , Tue, 18 Apr 2006 14:42:57
  • Why are you checking oil on a running engine?, Ken , Tue, 18 Apr 2006 14:03:45
    • Re: Why are you checking oil on a running engine?, Jimmy from Mass, Tue, 18 Apr 2006 16:08:56
  • Re: Dipstick, george chiassion, Tue, 18 Apr 2006 13:52:21

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• Prev by Date: Hmmm?, SPG, Wed, 19 Apr 2006 03:56:48
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