I recently had my LS/Vtec rebuilt and now I am having smoke come out of the breather on the valve cover. It is worse immediatly on startup but will also happen when driving around.

Is this oil getting by the rings and being burnt??

I am still running ND30 oil for break in.

 

most of the time my rebuilds smoke for a while. Its usually normal assuming its not smoking to much. after a few hundred miles or so it should go away. Takes some time befor the new rings get seated correctly. you can always go back and ask the shop you got the rebuild at if the amount of smoke you have it normal for the time being.

 

I expected to have smoke coming from the exhaust because of the rings having to get seated, but I did not expect smoke to come from the valve cover breather.

 

possibly a small amount of blow by ?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by supabang &raquo;</TD></TR><TR><TD CLASS="quote">possibly a small amount of blow by ?</TD></TR></TABLE>thats alot of blow by

 

when i had this problem on one of my LSvtecS it was caused because of a clog in the pvc system (the black box on the back) it caused a lot of smoke to come out of the breather

 

I believe the LS doesnt have that black box? Any other ideas?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by b18psi &raquo;</TD></TR><TR><TD CLASS="quote">I believe the LS doesnt have that black box? Any other ideas?</TD></TR></TABLE>Early LS has the box, later LS has that functionality built into the underside of the valve cover.

If you have a later LS block (without the box),
together with a GSR head/valvecover (which requires the box)...
Then you have to figure out how to achieve the proper crankcase venting.

How exactly is your PCV system set up?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by JimBlake &raquo;</TD></TR><TR><TD CLASS="quote">Early LS has the box, later LS has that functionality built into the underside of the valve cover.

If you have a later LS block (without the box),
together with a GSR head/valvecover (which requires the box)...
Then you have to figure out how to achieve the proper crankcase venting.

How exactly is your PCV system set up?</TD></TR></TABLE>

I think you are right about this, I need some kind of venting. I have a filter on the valve cover breather and the smoke is coming out of it. The car is also running bad (on 3 cylinders) and kept fouling plugs. I hope I havent damaged the rings or anything.

So becausr their is no ventilation all the pressure is coming out of the valve cover breather? What can I do to give some ventilation to the bottom end of the block?

 

I don't know how much work is to install a breather box on the block? Maybe that's the BEST solution.

You need a PCV valve coming from somewhere, going to the intake manifold.

I guess you could put a tee in your existing breather line. One side of the tee connects thru a PCV valve, then from there to the IM. Other side goes to the intake duct or your breather filter.

Normally, there will be enough vacuum thru the PCV valve to suck out that smoke. That's what happens in a stock setup. The oily crankcase vapor gets sucked into the IM so you don't realize it's there...

Maybe use a catch can to separate as much oil as possible from that air. That breather box does the same job as a catch can, it separates much of the oil out of the air, & lets the oil drain back to the crankcase.

Just for yuks, you realize it's illegal to vent that to the air... That's why the PCV and the breather line BOTH go to the intake.

 

My car has been fouling plugs and now it will only run on 3 cylinders. I think this ventilation problem could be the cause of that. Anyone agree?

I cant drill out the factory GSR location on the LS block beacuse it will get metal shavings inside the block. Anyone know of any possible ports I could use for a oil seperation system to be installed?

 

Try a catch can first, to see whether it solves the problem.

Put the can on the valvecover connection. Then branch the tube from there, one going to the intake (or breather filter) and the other going thru a PCV valve to the intake manifold.

I worry that it may not fix the misfiring. Right now, the baffles under the GSR valvecover don't do a thorough job separating the oil. But it isn't going into the intake, it's just making a mess in the engine bay... When the oil fouls up the breather filter, the crankcase pressure builds up. But that should cause other problems, not misfiring.

 

I am possibly blaming the misfiring on the complete lack of any ventilation on the bottom end of the block.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by b18psi &raquo;</TD></TR><TR><TD CLASS="quote">I am possibly blaming the misfiring on the complete lack of any ventilation on the bottom end of the block.</TD></TR></TABLE>
That's not going to cause a misfire. Reduced oil life, and sludge build-up are possible without a good pcv system.

Have you checked your compression? A lot of blowby combined with a running problem are usually related.