Priming the oil system and gas pedal position?

The idea of this is not to prime the oil system. The idea of this is to remedy the flooding that has occured by failed previous starts. The engine could very well fire up on half of the amount of fuel, and then as soon as it does, if you hold your foot to the floor, it's definately going to rev to the sky.

The idea is, if the car is flooded, it's not going to run very well even if it does finally fire. Opening the throttle completely does two things. 1) the computer cuts fuel back to try to relieve the situation of too much gas.

2) the opened throttle plate allows more air flow, also allowing the engine to correct the air/fuel ratio.

You should not need to prime the oil system on a regularly driven car, given you use good oil and don't use an oil filter without an anti-drainback valve (Fram filters do not have this... most other good brands do... stick with the Motorcraft filter that your vehicle came equipped with). The only time that the oil system should need primed is if the car has sat for an extended period of time and all of the residual oil that would normally be clinging to the parts has finally made its way to the oil pan. In this case, you need to either cut the spark (pull the coil wire, or the coil pack signal wires) and use the starter to get things moving, or manually drive the oil pump (if you have a vehicle with a distributor, if not, you're SOL).

HTH

JS

You got it.... "clear flood" strategy is only in effect when engine rpm is below 600 rpm. In a motor not flooded, there is enough gasoline present to get the motor above this threshhold in very few cranks...

Where possible, I like to "prelube" filters to shorten up un the dry running time but over the life of the engine I haven't seen any tangible difference in engine life - there's just way too many factors deciding that....

Jim Warman snipped-for-privacy@telusplanet.net

I do the same... fill the filter up as much as possible and still get it on the car without making a huge mess everywhere. Like you said, it's hard to say how much it helps, but it feels better than hearing the knocking while it's waiting for oil..

JS

** It didn't seem to have the desired results. I put the pedal-to-the-metal, ** turned the key, and WHOOSH -- the engine raced to a very high rpm.

Sounds like another famous 'aw shit' moment. I may not have clarified why I did it, and under what circumstance the computer will cut fuel delivery.

Normally, the computer will cut fuel in half *if* the engine turns over less than 600 RPM *and* the throttle pedal is floored (TPS signal high). This will clear a fuel overload condition and keep the cats from overheating while you crank. Even though fuel delivery is cut, there is still more than enough to fire the engine, and as you've discovered, once it catches and that 600 RPM limit is exceeded, VAAARRROOOOOOOOOOMMMMMMMMMMM she goes!

The only reason I purposely cut fuel delivery using this method was to keep the cats from overheating while priming a new oil filter, and *only* after pulling the signal connectors from both coil packs to keep the ignition from firing the engine. Even though I fill the oil filter prior to installing, I must crank the engine 10-15 seconds before achieving >5 psi., and at that point, I plug the coil packs back in and start normally. 30 seconds later, I shut it down and double-check the oil level.

Even though I use a primed Motorcraft 820-S filter, I dislike firing the engine until the entire lubrication system is fully pressurized. After completing this little ritual, subsequent cold starts aren't a problem, as the silicone anti-drainback valve in the filter keeps the top-end full of oil after a shutdown. It's only after draining the oil that air pockets become a problem, and that engine WILL run without oil pressure for a few seconds if 'The Ritual' is not performed.

Yes, it's anal as hell and I know mechanics these days don't bother with crap like this; it is a harmless old habit of mine, taught to be by a well-meaning Grandfather who took very good care of his beloved '52 Chevy until he died in

1992. Few mechanics even bother to prime the filter before installing these days, and frankly these days, most people don't know the difference and probably wouldn't care even if they did.

So there you have it. Sorry for the misunderstanding.

pedal-to-the-metal,

Ahhh! Thanks for clearing this up. Fortunately, I did it on the Explorer and had already started it, so there was plenty of oil in the system. Of course, it scared the hell out of the cat who was sleeping on the intake manifold. ;-D

Bob '03 Cobra coupe