Cylinder Leakage, PCV valve, Manifold Vacuum

I used the lift outside the main indoor area. These lifts were a bit strange. There was a center column and 4 movable arms. At the end of each lift arm was an adjustable metal pad. These pads can be adjusted so that there is a slight upward angle to keep the car's underbody from impacting the lift's arms.

Cylinder Leakdown Test

21mm crankshaft bolt

Measured 12%, 24%, 14%, 6% for cyls 1,2,3,4


Firing order 1-3-4-2

The nice feature on the Mazda is that there is already a hole in the wheel well cover to access the crankshaft bolt. I turned the bolt until the timing mark lined up with the TDC marking for cyl 1. The timing mark is found on a ring between the two concentric crankshaft pulleys.

To put the next cylinder in the firing order at TDC, I turned the bolt 180 deg. (720/# cylinders). Putting a long screwdriver down the spark plug hole helps indicate when TDC is reached. It's hard to estimate if I've turned the bolt 180 deg because of the limited room to turn the rachet.

As for the leakage, I couldn't feel or hear any air from the exhaust, oil filler hole or dipstick tube. I also didn't see any bubbles in the coolant at the radiator cap. I didn't take off the air filter (intake valves) because it's too troublesome to remove the air box cover. So I don't know the source of the leakage. The only hissing air sound was from the spark plug well where the air hose was plugged in. What's that from? Was it from the other cylinders since I had removed all the spark plugs at the same time?

Manifold Vacuum

Use PCV vacuum source

20" vacuum

Needle varies between 20-21". Needle steady for about 0.5 secs, then vibrates for 1-2 secs, and repeats the entire cycle. Applying pressure to the vacuum fitting could make needle steady at 20".

PCV Valve Check

PCV valve check. It's OK.
Why does air come out of the oil filler hole?