Too Much Vacuum? need answers from PRO'S
01-19-2008, 12:05 PM
#1
Launching!
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Too Much Vacuum? need help from anyone, PLZ hello everyone,
well let me fisrt state what i have underthe hood before i get to the problem.
i have a 346ci built by FMS 4 years ago with custom pistons, 6.125 eagle rods with all high performance bearings and a LS6 heads heavly ported with 2.055/1.6 and 59cc. the valvetrain is all solid roller from lifters, cam and rockers, toped with wegner carb intake and 90mm TB and kooks step hearders.
ok, here is goes. 3 days ago, i noticed the engine is Weaseling sound while driving , as if i have a turbo under the hood. well i opened the hood, everything was normal, i tried to open the oil cap and i couldnt open it, as if something sucking the cap. by force i pulled it and the engine is sucking air like a vacuum cleaner. it was sol load it sounded like a blow-off from a turbo system. i removed all PCV lines and still both sides of the heads are suck air madly that the oil started to get inside the combustion chamber and burn the oil. that car is smoking (white and black color) asif on fire when on full throttle.
if the car at idle , still white smoke is coming out and the vacuum is to strong as if there is a pump inside the oil pan
any thoughts or ideas
Hussain
well let me fisrt state what i have underthe hood before i get to the problem.
i have a 346ci built by FMS 4 years ago with custom pistons, 6.125 eagle rods with all high performance bearings and a LS6 heads heavly ported with 2.055/1.6 and 59cc. the valvetrain is all solid roller from lifters, cam and rockers, toped with wegner carb intake and 90mm TB and kooks step hearders.
ok, here is goes. 3 days ago, i noticed the engine is Weaseling sound while driving , as if i have a turbo under the hood. well i opened the hood, everything was normal, i tried to open the oil cap and i couldnt open it, as if something sucking the cap. by force i pulled it and the engine is sucking air like a vacuum cleaner. it was sol load it sounded like a blow-off from a turbo system. i removed all PCV lines and still both sides of the heads are suck air madly that the oil started to get inside the combustion chamber and burn the oil. that car is smoking (white and black color) asif on fire when on full throttle.
if the car at idle , still white smoke is coming out and the vacuum is to strong as if there is a pump inside the oil pan
any thoughts or ideas
Hussain
Last edited by Solid346; 01-19-2008 at 12:25 PM.
01-20-2008, 08:22 AM
#7
try disconnecting the pcv where it attaches to the throttle boddy and plugging it at the throttle body. If that eliminates the problem then it's as the others have said a PCV valve that is stuck open allowing full intake vacumn to pull the crank case vapors.
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01-20-2008, 09:47 AM
#10
Vacuum Issue I agree with what Ed says. 
Typically, in a ported cathedral head, the portion of the casting covering the rocker stud hole is removed as part of the process, and if the studs are not properly sealed, the intake ports will pull oil and air through the threads around the stud.
If you were not the assembler of the heads, you need to remove one of the studs and check for sealant on the threads. It's also possible that the wrong type of sealant could have been used, causing it to dissolve/deteriorate with exposure to heat and petroleum products.
Typically, in a ported cathedral head, the portion of the casting covering the rocker stud hole is removed as part of the process, and if the studs are not properly sealed, the intake ports will pull oil and air through the threads around the stud.
If you were not the assembler of the heads, you need to remove one of the studs and check for sealant on the threads. It's also possible that the wrong type of sealant could have been used, causing it to dissolve/deteriorate with exposure to heat and petroleum products.
01-20-2008, 03:29 PM
#11
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well there is a pcv line goes straight to the elbow, and when i removed it that line still sucks air mad. also removed all pcv lines and it keeps sucking air. i think i have to remove the heads or valve covers to see the T&D rockers if they are not sealed, like Scatillac and Ed pointed. but i hope there is no crack in the heads that csuing the air suction 
04-29-2008, 06:46 PM
#12
Talk about bringing it back from the DEAD!
I would appreciate your HELP guyz, I have fouled 2 sets of spark plugs and 1 o2 sensor from the passenger side only!
I too am blowing smoke!
I am also pulling a **** load of air through the PCV hoses leading back to the intake, I also have a catch can and if I squeeze any of those hoses that lead to the catch can, the car boggs down alot but doesnt shut off.
If I put my hand over the oil fill tube I can feel it sucking my skin down.
If I pull the dip stick out and put my finger to cover the tube it also wants to pull my skin down from my finger.
If I squeeze the hose that leads to the valve cover from the top of the UMI 90mm TB (opposite of the IAC motor) the car also wants to bogg down.
All this after a Harland Sharp 1.8 RR and a patriot gold spring kit install!!!
Should a sealer been used to bolt the rockers down? because I have stock 241's
I would really appreciate any help!
Thanks in advance
Zeke
I would appreciate your HELP guyz, I have fouled 2 sets of spark plugs and 1 o2 sensor from the passenger side only!
I too am blowing smoke!
I am also pulling a **** load of air through the PCV hoses leading back to the intake, I also have a catch can and if I squeeze any of those hoses that lead to the catch can, the car boggs down alot but doesnt shut off.
If I put my hand over the oil fill tube I can feel it sucking my skin down.
If I pull the dip stick out and put my finger to cover the tube it also wants to pull my skin down from my finger.
If I squeeze the hose that leads to the valve cover from the top of the UMI 90mm TB (opposite of the IAC motor) the car also wants to bogg down.
All this after a Harland Sharp 1.8 RR and a patriot gold spring kit install!!!
Should a sealer been used to bolt the rockers down? because I have stock 241's
I would really appreciate any help!
Thanks in advance
Zeke
Last edited by litle88; 04-30-2008 at 03:52 AM.
04-30-2008, 07:44 AM
#14
forget to take a rag out of the throttle body or something?
post a pic of how you have the pcv routed now... i have a feeling the line from the passenger front valvecover to the top of the throttlebody is blocked or they are swapped between that one and the other one that goes to the side of the intake.
post a pic of how you have the pcv routed now... i have a feeling the line from the passenger front valvecover to the top of the throttlebody is blocked or they are swapped between that one and the other one that goes to the side of the intake.
05-01-2008, 05:55 PM
#18
That would be my guess. One iteration of my PCV setup I ran just the valley pan/PCV line and capped both vents to see what would happen. It was exactly as you are describing. Vacuum on teh oil fill and the same noise. I only ran for about 30 seconds before I changed that.