Oil seal vacuum tolerance
Oil seal vacuum tolerance
(OP)
We are installing a postive crankcase ventilation system on an old engine. The pcv valve creates a vacuum in the crankcase of about 7 inches of water. We are concerned about the effect of vacuum on seal performance, and if this vacuum is enough to draw dirt into the engine. The catalogs I have only specify the maximum positive pressure. Can anyone help?
Thanks,
John Woodward
Thanks,
John Woodward





RE: Oil seal vacuum tolerance
7 inches of water can be absolute or relative. Relative this under-pressure does not produce a big force.
However 7 inches water absolute nearly produces the full force : 100 kg/m^2.
Finally: if the seala leaks due to a vacuum load it "definitely" will take in dirt (or whatever else is available for mass transport).