[bagdnbdrpt]

i have got a chevy 355. a couple years ago i switched from a low rise valve cover to a tall high rise valve cover, after i did this i get smoke coming out of my breather, constantly.. as soon as i start to turn the engine over and when it starts running it smokes out of the breather, i then pulled the motor from the truck it was in and put it in my blazer, well i finally got the engine in and running and now i remember about this smoking problem. anyone have any idea what it could be?... i figure it has something to do do with the valves or rockers or something.. not much of an internal engine guy?

 

[jameskirk1]

You need to rig up a PCV system. If the "mist" coming out is at a slow rate it is normal. If it is actually smoke, you've got problems!

 

[bagdnbdrpt]

umm it is just like vapor, or i dunno how to explain it... its almost like when you drop oil or some fluid on your exaust and it burns off and gives off that light smoke.. its not smoking like a black smoke or thick smoke its just annoying.. and i have a pcv valve on the other valve cover.. i also dont have any of the vaccum hoses hooked up yet?

 

[monzadood]

it could be blow-by. which translates to a very high-mileage engine.

 

[bagdnbdrpt]

this engine was fully rebuilt a few years ago and probably has maybe 30,000 since it was rebuilt?

 

[RedGT]

I had the same problem with my 355. The problem was I dident have a PCV system hooked up like jameskirk1 suggested. When you went with the tall valve covers did you reinstall a PCV system or did you just install breathers. If you just have breathers it could damage your engine. (It blew all the oil gaskets out on my motor).

 

[bdazgmc]

what your seeing is probably just a little blow by hook up your pcv valve if its not that bad you should be ok

 

[results]

for sure hook up the pvc system or at least breathers in the covers so the motor can get air

 

[Danny350]

That's not what they're for at all^

"pcv" stands for positive crankcase ventilation.

There's always gonna be a bit of pressure in the crankcase from combustion gases leaking by the rings, the pcv system re-burns them for environmental purposes. Back in the day the just had hoses running behind the engine and the shit would just leak out on the ground.

 

[RedGT]

That's not what they're for at all^

"pcv" stands for positive crankcase ventilation.

There's always gonna be a bit of pressure in the crankcase from combustion gases leaking by the rings, the pcv system re-burns them for environmental purposes. Back in the day the just had hoses running behind the engine and the shit would just leak out on the ground.

The PCV system actually creates a vacuum in the crankcase that evacuates excess pressure.

 

[bagdnbdrpt]

so how do you correctly hook up a pcv system?

 

[T Man 383]

Pass side valve cover put a pcv valve in, run a hose "T'eed" into the brake booster line (which runs into the big vacuum hole in the carb)

 

[jameskirk1]

You also need a breather on the drivers side valve cover to make the above work properly. That keeps fresh air circulating through the crankcase...

The advantages to a non-emissions car are longer intervals to oil change and no oily mess in engine compartment. I ran an "open" setup (non-PCV) on my old 305 with some circle track valve covers and some open element breathers. The entire underhood area would be coated in a thin dirty covering of oil in no time at all...Switched to PCV setup and all that went away...