How to find an engine oil leak using crankcase pressure

This is how the pros find motor leaks without dye oil. Quickly.
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[@spelunkerd]

This is very similar to the test recommended by Chrysler to verify a plenum pan leak in the early ('98 and on) Rams. Cap off PCV, dipstick and breather, run engine and watch to see if manifold vacuum appears in the crankcase. As you show, normal response with PCV etc capped is a tiny positive pressure from blowby. Interesting to see another application.

[@CHIBA280CRV]

That was a clever and informative video thanks 👍

[@yusuihang]

Very interesting that pressure was still so low with vents plugged. I was thinking of using this method (putting guage on oil tube) to test PVC system is venting properly.

[@reillyfox1989]

Perhaps pressurizing the crank case as you have done and then use soapy water the same way you test for an air leak? if oil can escape air sure can, seems it would be faster.

[@RustBeltAuto]

The trick is to devise a way to do it with low enough pressure to not blow a seal. Smoke machines work too. Soapy water also does not work very well on really large leaks. This is a very old way to find a leak. Most people who do this have died of old age.