PCV test

[ScottA]

I have a newish to me Jeep. I have the engine running pretty good. My question has to do with a little smoke coming out the exhaust, as it may relate to the PCV system.

First some details. I am pulling 18.5 psi of vacuum. Compression is between 87 an 95 on all cylinders. Valves are ajdusted. The only vacuum leak I have is around the throttle shaft(minor leak).

At the 3/8 tube that connect the dipstick to the crossover tube, there is no noticeable vacuum. In fact i can feel a pulsing feeling.

I did remove and clean the pcv, it was surprisingly clean. Replaced it and it made no difference. Could this be the source of the light smoke? Can the spring in the pcv be replaced?

Thank You

[scoutpilot]

[size=12]What color is the smoke? Blue? Oil is burning, maybe worn rings. Black? This would be an overly rich fuel/air mix. White? This would indicate a crack in the head gasket or the head or the block. Does the smoke only appear when cold starting, then it goes away after a while or is constant? Is there coolant/water in the oil?[/size][/b]

[ScottA]

The Smoke seems to be more white than anything else. I will check the head to make certain the nuts are torqued correctly.

I am curious if the pcv at idle would create any measurable amount of vacuum?

[ScottA]

So I had some time to play with the Willys this afternoon. I did have the idle adjusted a little high (900 rpm). I turned the idle screw in a little bit and adjusted the throttle screw as well. not it idles at a consistent 650 rpm.

Doing that helped, the smoke is almost gone at idle. When you snap the throttle I get black smoke. The idle screw is adjusted 1 3/4 turns out.

Now the latest development is at an idle while warm I now have a puff puff every once in a while. This is accompanied by a .5 psi drop in the vacuum gauge. Which by the way is reading 20 pounds now (after fiddling the dist a little more). Looks like I will be doing a valve adjustment on Sunday.

Question, can the metering rod setting cause a rich mixture? Where is one able to order the carter guage? I made my own from some instructions I found online, I'm not sure I fully trust my work though, lol.

[scoutpilot]

[size=12]The PCV does not itself create vacuum. The vacuum is created in the cylinders. http://oldjeepcarbs.freeforums.net/thread/66/final-design-l134

�The only vacuum leak I have is around the throttle shaft(minor leak).� This is the reason you have black smoke. As the leak gets worse, you�ll find yourself enriching the mixture ever more to make up for the increased air infiltration around the shaft. Eventually, it won�t idle at all unless you apply some choke to curtail the air flow.

The numbers you have posted indicate the motor and carb are getting tired.[/size][/b]