oily intake runners
#1
8 Second Club
Thread Starter
iTrader: (76)
Join Date: Jun 2004
Location: Goshen NY
Posts: 2,902
Likes: 0
Received 0 Likes
on
0 Posts
![](https://ls1tech.com/forums/images/ranks/ls1tech10year.png)
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
i took the fast intake off my car and now the intake runners are like oil coated and if u shine a lite down the runner u can see oil sitting on top of the intake valve. i also had the one line that goes from the valve cover to the tb pluged off and when i took the oil cap of it had about 10psi of crank case presure so i hooked that line back on.
#4
8 Second Club
Thread Starter
iTrader: (76)
Join Date: Jun 2004
Location: Goshen NY
Posts: 2,902
Likes: 0
Received 0 Likes
on
0 Posts
![](https://ls1tech.com/forums/images/ranks/ls1tech10year.png)
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
Originally Posted by oange ss
that would be the fresh air supply for the pcv system, which needs to hooked up
#5
8 Second Club
Thread Starter
iTrader: (76)
Join Date: Jun 2004
Location: Goshen NY
Posts: 2,902
Likes: 0
Received 0 Likes
on
0 Posts
![](https://ls1tech.com/forums/images/ranks/ls1tech10year.png)
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
i also read with the fast 90mm setup that u deff need the catch can setup on 98s
ive also have been runign the clear fuel filter inthe pcv line and it does nothing.
ive also have been runign the clear fuel filter inthe pcv line and it does nothing.
Last edited by SSPerformance; 08-11-2005 at 08:18 PM.
Trending Topics
#10
TECH Enthusiast
Join Date: Dec 2002
Location: Chattanooga,TN
Posts: 736
Likes: 0
Received 0 Likes
on
0 Posts
![](https://ls1tech.com/forums/images/ranks/ls1tech10year.png)
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
Are your plugs black? Did you put thread sealer on your rocker arm bolts? I have the same problem, but my plugs were fouled out and black as hell and intake runners had oil everywhere and I had a vaccum leak that I couldn't find. Well I takked to a mechanic friend of mine and he said that every ported head that he had installed he had to put silicone on the rocker arm bolts to keep them from leaking air and oil into the intake runners. Oil was dripping right on to my spark plugs.
#12
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
I don't see how a leak at the rocker could get oil into the intake.
And definintely DON'T plug the valve-cover-to-intake hose. This is essential to pull air through the engine when the vacuum side of the PCV system is operating, and even more essential to alow reverse-flow under high manifold pressure conditions.
10 psi of crankcase pressure will blow seals out (are things leaking already?). You might want to use the GM check to see if the crankcase is overpressurizing: Disconnect and plug the valve-cover-to-intake hose (for the test only!). Next, take out the oil dipstick and attach a vacuum/pressure gauge to the dipstick tube. Run the engine at idle for a couple of minutes, then increase the speed to about 1800 to 2000 rpm for about 20 or 30 seconds. At no point in this test should you see pressure on the gauge. And generally, you should see some vacuum at idle. If the test shows you're pressurizing the crankcase, run a compression or leakdown test and try to figure out where it's coming from.
Sometimes, if it's just a little extra pressure, you can get one of the orifice-type PCV "valves" and open up the orifice a bit so that you can draw more air through the system.
Of course, some of you guys with racing engines running 12.5:1 compression will tend to pressurize the crankcase often, in which case you're probably running a scavenging vacuum pump to avoid pressure build-up.
And definintely DON'T plug the valve-cover-to-intake hose. This is essential to pull air through the engine when the vacuum side of the PCV system is operating, and even more essential to alow reverse-flow under high manifold pressure conditions.
10 psi of crankcase pressure will blow seals out (are things leaking already?). You might want to use the GM check to see if the crankcase is overpressurizing: Disconnect and plug the valve-cover-to-intake hose (for the test only!). Next, take out the oil dipstick and attach a vacuum/pressure gauge to the dipstick tube. Run the engine at idle for a couple of minutes, then increase the speed to about 1800 to 2000 rpm for about 20 or 30 seconds. At no point in this test should you see pressure on the gauge. And generally, you should see some vacuum at idle. If the test shows you're pressurizing the crankcase, run a compression or leakdown test and try to figure out where it's coming from.
Sometimes, if it's just a little extra pressure, you can get one of the orifice-type PCV "valves" and open up the orifice a bit so that you can draw more air through the system.
Of course, some of you guys with racing engines running 12.5:1 compression will tend to pressurize the crankcase often, in which case you're probably running a scavenging vacuum pump to avoid pressure build-up.
#13
8 Second Club
Thread Starter
iTrader: (76)
Join Date: Jun 2004
Location: Goshen NY
Posts: 2,902
Likes: 0
Received 0 Likes
on
0 Posts
![](https://ls1tech.com/forums/images/ranks/ls1tech10year.png)
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
i think i may have found hte problem i changed to the 99 and up valve cover and i could not find a fitting to allow the house to fit in the gromet in the drive side valve cover so i found a pcv valve at work that had noting in it. so i used that and the side the sits down in valve cover only had a hole the size of a pen tip. maybee that whouldent allow enought vacume to pull the presure out of the crank case.
#16
TECH Enthusiast
Join Date: Apr 2003
Location: silver Spring MD
Posts: 561
Likes: 0
Received 0 Likes
on
0 Posts
![](https://ls1tech.com/forums/images/ranks/ls1tech10year.png)
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
Hi Folks
I think that is typical for LS1 and I had the same issue with 3000 miles on the car. A Catch Can will help but may not totally eliminate the problem but it does help.
Thanks
Bill
PS: the only thing I did not like was the oil ring on the head around cylinder # 3 – like it was not sealing correctly
I think that is typical for LS1 and I had the same issue with 3000 miles on the car. A Catch Can will help but may not totally eliminate the problem but it does help.
Thanks
Bill
![The Patriot !!](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_patriot.gif)
PS: the only thing I did not like was the oil ring on the head around cylinder # 3 – like it was not sealing correctly
#17
TECH Enthusiast
Join Date: Dec 2002
Location: Chattanooga,TN
Posts: 736
Likes: 0
Received 0 Likes
on
0 Posts
![](https://ls1tech.com/forums/images/ranks/ls1tech10year.png)
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
Originally Posted by 30th droptop
I don't see how a leak at the rocker could get oil into the intake.
#18
8 Second Club
Thread Starter
iTrader: (76)
Join Date: Jun 2004
Location: Goshen NY
Posts: 2,902
Likes: 0
Received 0 Likes
on
0 Posts
![](https://ls1tech.com/forums/images/ranks/ls1tech10year.png)
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
Originally Posted by 1ORANGEWS6
Are your plugs black? Did you put thread sealer on your rocker arm bolts? I have the same problem, but my plugs were fouled out and black as hell and intake runners had oil everywhere and I had a vaccum leak that I couldn't find. Well I takked to a mechanic friend of mine and he said that every ported head that he had installed he had to put silicone on the rocker arm bolts to keep them from leaking air and oil into the intake runners. Oil was dripping right on to my spark plugs.
#19
8 Second Club
Thread Starter
iTrader: (76)
Join Date: Jun 2004
Location: Goshen NY
Posts: 2,902
Likes: 0
Received 0 Likes
on
0 Posts
![](https://ls1tech.com/forums/images/ranks/ls1tech10year.png)
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
Originally Posted by Bill's 02 Z-28 SS
Hi Folks
I think that is typical for LS1 and I had the same issue with 3000 miles on the car. A Catch Can will help but may not totally eliminate the problem but it does help.
Thanks
Bill
PS: the only thing I did not like was the oil ring on the head around cylinder # 3 – like it was not sealing correctly
I think that is typical for LS1 and I had the same issue with 3000 miles on the car. A Catch Can will help but may not totally eliminate the problem but it does help.
Thanks
Bill
![The Patriot !!](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_patriot.gif)
PS: the only thing I did not like was the oil ring on the head around cylinder # 3 – like it was not sealing correctly