Make sure ALL crankcase pressure is forced through the meter.

2.     Plumb meter with ˝” or larger heater hose.  (Bottom hole is inlet.)

The fewer bends in the hose, the better.

3.     Discharging plumbing is not necessary.  (Leave top hole open.)

4.     Mount meter in vertical position.

5.     Be sure to disconnect and plug Vacu-Pan for testing.

A reading of 7 (at any steady RPM) indicates excessive crankcase pressure which indicates improper ring seal or extreme turbulence in the crankcase caused by improper pan, scraper, return, etc.

We have done a lot of dyno testing with Blow By Meters and feel that they are a very useful tool for indicating crankcase pressure.  Below are a few interesting observations we have found during testing.

On a very competitive Can-Am Chevrolet motor, the meter would read no higher than 1-2 on the scale until 6,500 RPM.  Then it would “jump” to 5 and gradually settle to about 3.  (This could be ring flutter.)

The meter was installed on the same motor with a stock oil pan with no windage tray or scraper.  At 4,000 RPM it blew the ball out of sight.  This is not because all the rings went out.  

I mention the above observations to make you aware of the fact that the meter measures flow very accurately – but all flow is not necessarily ring blow by.

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