Updated valve cover w/ PCV
Updated valve cover w/ PCV I've noticed that searching youtube and google produces information on using the updated valve cover (I think 2011 and up) for older engines to help with blue smoke on startups because of the updated pcv valve baffling. I can't seem to find info on this site, though. The part number for the new valve cover is GM# 12642655. Has anyone used this?
Thanks,
Brandon
Thanks,
Brandon
It has about 130,000 or so. I have read about the valve seals but a lot of other people report solving the issues with the newer style valve cover/pcv, as apparently the design that I have was known to suck oil and cause issues on startup as well.
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I would first ascertain that you don't have worn seals/valve guides.
I’ve heard that the later (Gen IV I guess) motors had a revised crankcase vent system to minimize pulling oil into the intake. Mine has the small orifice’s in the valve cover make-up air nipples - to restrict how hard the motor (vacuum) can “pull” on the crankcase.
In the day, the valve guide/seal test was, put in first gear, and with some one following in another car accelerate hard up to 5500 rpm or so, then abruptly let off the gas. As the car decelerates, have the person following look for blue oil smoke. High vacuum in the cylinder on deceleration pulls oil under the valve cover past worn seals/guides.
In the day, the valve guide/seal test was, put in first gear, and with some one following in another car accelerate hard up to 5500 rpm or so, then abruptly let off the gas. As the car decelerates, have the person following look for blue oil smoke. High vacuum in the cylinder on deceleration pulls oil under the valve cover past worn seals/guides.
I have solved oil consumption on several DoD trucks with the change up valve cover. The new valve cover has a PCV baffle that extends below the rocker arms between cylinders #5 & #7 . But give parts guy the last 8 digits of your vin to get the latest part number.
PCV pullover or an overactive lifter can cause oil to be pulled through the PCV system even at low vehicle mileage. A correctly functioning PCV system will only leave a film of oil in the intake manifold. Inspect the intake manifold to see if there is any oil puddling in the bottom. If there is you will need to replace the left valve cover. Two new left rocker arm covers have been released for trucks and vans. Technicians should replace the left rocker arm cover with GMP/N 12570427 for 2007-2008 or GMP/N 12642655 for 2009-2011. This rocker arm cover has a relocated PCV drain hole that prevents oil from entering the intake manifold.
Russ Kemp
PCV pullover or an overactive lifter can cause oil to be pulled through the PCV system even at low vehicle mileage. A correctly functioning PCV system will only leave a film of oil in the intake manifold. Inspect the intake manifold to see if there is any oil puddling in the bottom. If there is you will need to replace the left valve cover. Two new left rocker arm covers have been released for trucks and vans. Technicians should replace the left rocker arm cover with GMP/N 12570427 for 2007-2008 or GMP/N 12642655 for 2009-2011. This rocker arm cover has a relocated PCV drain hole that prevents oil from entering the intake manifold.
Russ Kemp
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If you haven't already, I suggest asking in the Gen III/IV External Engine forums, as that will give you a wider audience than just folks who have done an LS swap.
I finally was able to find this info in case it may be helpful:
This is GM's third attempt to mitigate the oil consumption issues plaguing LS1 engines and 1999-2013 LS engine trucks. For some reason the engine eats oil through the PCV setup and people who run catch cans catch a significant amount of oil. For millions of engines that don't it pools up in the intake. I was surprised when I pulled the intake manifold on my truck to see oil weeping out of the intake runner outlets.
New GM valve cover. Includes new gasket and grommets. Part number 12570427 for 2009-prior LS engines which has the hose connector barb for the PCV tubing. 12642655 is for 2010-2013 LS engines which uses a push on fitting connector.
This is GM's third attempt to mitigate the oil consumption issues plaguing LS1 engines and 1999-2013 LS engine trucks. For some reason the engine eats oil through the PCV setup and people who run catch cans catch a significant amount of oil. For millions of engines that don't it pools up in the intake. I was surprised when I pulled the intake manifold on my truck to see oil weeping out of the intake runner outlets.
New GM valve cover. Includes new gasket and grommets. Part number 12570427 for 2009-prior LS engines which has the hose connector barb for the PCV tubing. 12642655 is for 2010-2013 LS engines which uses a push on fitting connector.
I can't remember where exactly I found it. I believe it was on a website someone made documenting the problems they'd had and information on how they fixed it, which included picture. I'm not sure about LSA motors.