the background:
I have a 2000 c5 and it is using oil. a little over a liter every 5-6000 KM. I also had tiny spots/dots of (what I assume is) oil on the rear end of the car. as such I decided to add a catch can to try and stop the problem. at the same time I added and LS6 intake manifold (new gaskets also). when I did the install I broke the vacuum line to the HVAC controller (air from all vents and no ability to switch from floor, defrost, etc). I have run a new vacuum line so that will be fixed when I reinstall the manifold.

the problem:
the runners on the heads are black! see my horrible pics below. I dont have pics from last year when the intake was swapped but I am sure they were not black like they are now.




the catch can I installed is from ebay (ie cheap). I know some will say that is my problem but I know many on this site have had success with these. the oil on the rear was reduced all last summer but I really didn't see any in the catch can. there does not seem to be a lot of oil in the manifold...but I believe there is more in the new manifold than there was in the stocker when I removed it.

what do I do?
I am planning on ordering an 04 valley cover with the internal PCV. I was also planning on removing the catch can. is it possible I installed the catch can backwards? I will clean the heads as best I can (as they are not going to be removed).

any other suggestions, thoughts or ideas?

 

some one out there has an opinion...

 

week day bump...

 

That's interesting...my Y2K doesn't have nearly that much oil in the intake, and it has the factory PCV setup. Out of curiousity, what rpm range do you keep the motor in around town? I have no way to be sure, but I keep mine under 1700 almost all of the time, and think that it helps reduce the amount of cylinder vacuum that might un-seat the rings and cause blow-by. Could be completely foolish of me, but with ~100,000km on the clock and using ~1 liter every 20,000km, it seems to be working.

 

Not a big deal but this is why some use a Catch can. At higher RPM's there can be a lot of blowby on the LS engines. It generally gets sent back to the intake to get burned making the intake oily. You amount of oil consumption does not seem like a problem.

 

thanks guys glad to hear the consumption isn't that bad.

I normally drive in the lowest rpm I can however, I take most opportunities given to accelerate but the opportunities are only a few times a week.

I looked at my stock ls1 intake tonight which was on the car for 90k-ish km and the two are equally dirty...but the ls6 has only been on the car for 5-6k km and it was very clean when I put it on.

since I am sure the intake side of the engine is dirtier after 5k km than the stock system was after 90k km, should I remove the cheap ebay catch can?

I'm going to update the pcv system since its open.