How much blow-by is too much?

SPoole · Post by **SPoole** » Thu Oct 16, 2008 2:07 pm

I am new to Hondas so I am not sure but my car has quite a bit of crank case pressure. At idle I have a steady stream of light bluish smoke coming from my 2 valve cover vent hose. Is that a sign of badness happening inside? I have checked plugs and all 4 are extremely consistent so I would think that it would not be a single bad cyl, and I had the head off recently and everything looked great inside plus I put the head back on completely rebuilt.

Post by **Gaskleppie** » Thu Oct 16, 2008 2:26 pm

If you want to expand your engine life, make a crank ventilation system that is big enough. Like mine:

the can is not ready yet and its upside down. It works very good. I lowered the oil use of my old stock B16 on trackdays with almost half! I use a plastic old oil can at this moment.

SPoole · Post by **SPoole** » Thu Oct 16, 2008 2:33 pm

So the blow-by I am seeing isnt a sign of a problem?

shogun · Post by **shogun** » Thu Oct 16, 2008 2:57 pm

very good idea. The goal is limitation of crank oil pressuree?

Post by **Gaskleppie** » Thu Oct 16, 2008 4:12 pm

So the blow-by I am seeing isnt a sign of a problem?

Its always better when you have no blow-by but when you have it, its better to let it out the easiest way possible. the big advantage of this system are the oversized hoses. Thick hoses reduce the air/oil speed inside the hoses and it gives the oil a better chance to drain back to the engine instead of blowing away.

HiProfile · Post by **HiProfile** » Fri Oct 17, 2008 9:54 pm

Tired dohc vtec motors are known to burn oil, since it sucks oil through the rings, burns it, and some in turn is pushed back through the rings as smoke. Although Honda uses low tension rings, that amount of blowby is somewhat excessive. My D15B2 beater blows a good deal of air from the breather at idle (no smoke though), and still gets 40mpg and burns no oil. Catch cans will help, and in more than one way. The PCV valve could start feeding that messy air to the motor, which will clog up valves, and possibly cause detonation in severe conditions.

SPoole · Post by **SPoole** » Mon Oct 20, 2008 1:16 am

It is an H22 with all aftermarket internals, and I do not have PCV hooked up. I have just been venting the 2 valve cover hoses. I have been considering hooking my vents up to a siphon that I will set up in my wastegate dump. Should I have the PCV hooked up or does it matter.