too much crankcase pressure? popped pcv out
04-27-2014, 08:48 PM
#1
too much crankcase pressure? popped pcv out Recently got done swapping my 317 heads with the ls6 heads from a buddy of mine. also installed a ported tb from the truck engine where theres no vac hose(i'll get into soon) and i was able to drive it home last week. havent been able to drive it until today and this whole issue started to happen.
so currently my PCV setup is pcv sitting in on the drivers sdie and a hose that goes to a catch can and then goes into the LS6 intake manifold. since the truck tb doesnt have a vac port, the passenger side valve cover vac was capped. so today with the motor running i heard a squeeky sound that resembles a loose belt but it wasnt coming from the belt/idler pulley. i narroed it down to the pcv and i decided to go get a new one and install it in. once the new one was installed the squeeky sound was gone, so i thought. took the car out for a drive and got on it a few times. on the last one when i left off on the top of 3rd gear i heard a baning sound like some metal broke and then i looked behind my rearview mirrow and blue smoke was coming from under the car. the cabin slowly was filling up with blue smoke.
i pulled into a nearby sonics where the locals hang out and pooped the hood. oil was everywhere and i noticed the pcv was out from the valve cover and oil spewed out and everywhere. oil level and pressure's all fine after i cleaned as much of the oil around the engine bay as possible. i have heard ppl blowing piston rings from over-ventilation in the crankcase and that leads to major rebuilds and such? my question is, how bad is this? i just orderd a metco valve cover breather as my buddy suggested i get it and just remove the pcv system, but i dont know if the damage's already been done?
so currently my PCV setup is pcv sitting in on the drivers sdie and a hose that goes to a catch can and then goes into the LS6 intake manifold. since the truck tb doesnt have a vac port, the passenger side valve cover vac was capped. so today with the motor running i heard a squeeky sound that resembles a loose belt but it wasnt coming from the belt/idler pulley. i narroed it down to the pcv and i decided to go get a new one and install it in. once the new one was installed the squeeky sound was gone, so i thought. took the car out for a drive and got on it a few times. on the last one when i left off on the top of 3rd gear i heard a baning sound like some metal broke and then i looked behind my rearview mirrow and blue smoke was coming from under the car. the cabin slowly was filling up with blue smoke.
i pulled into a nearby sonics where the locals hang out and pooped the hood. oil was everywhere and i noticed the pcv was out from the valve cover and oil spewed out and everywhere. oil level and pressure's all fine after i cleaned as much of the oil around the engine bay as possible. i have heard ppl blowing piston rings from over-ventilation in the crankcase and that leads to major rebuilds and such? my question is, how bad is this? i just orderd a metco valve cover breather as my buddy suggested i get it and just remove the pcv system, but i dont know if the damage's already been done?
04-28-2014, 06:17 AM
#6
i'm just hoping it didnt crack a ringland..... but i think i did. havent done a compression test or leakdown test yet but i want to try and diagnose everything else before i do that (or have my buddy do it). i just dont understand how there's too much crankcase pressure even even with the pcv setup im using 
edit-and i noticed when i pooped the hood the dipstick popped up a bit too unfortunately. cant recall if any oil was on it or not or if the oil erupted from only the pcv port on drivers' side.
but i think i did. havent done a compression test or leakdown test yet but i want to try and diagnose everything else before i do that (or have my buddy do it). i just dont understand how there's too much crankcase pressure even even with the pcv setup im using edit-and i noticed when i pooped the hood the dipstick popped up a bit too unfortunately. cant recall if any oil was on it or not or if the oil erupted from only the pcv port on drivers' side.
Last edited by fst100; 04-28-2014 at 07:46 AM.
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04-28-2014, 01:19 PM
#11
currently at work but its pretty simple:
PCV valve sitting in on drivers side. cant recall the ID of the hose but its whatever that fits over the PCV (5/8"?), from there goes to a homemade oil seperator catch can (there was a DIY link that you can get the oil/water separator at Lowes) and from there goes into the intake manifold. since the TB i have is a truck style 5.3 that has no vacuum port, the one port off the passenger valve cover was covere with a rubber cap. thats basically it.
PCV valve sitting in on drivers side. cant recall the ID of the hose but its whatever that fits over the PCV (5/8"?), from there goes to a homemade oil seperator catch can (there was a DIY link that you can get the oil/water separator at Lowes) and from there goes into the intake manifold. since the TB i have is a truck style 5.3 that has no vacuum port, the one port off the passenger valve cover was covere with a rubber cap. thats basically it.
04-28-2014, 01:57 PM
#13
no, its on the passenger side. the hose goes from pcv on driver's side going behind the intake mani and on passenger side. the catch can's just hovering on that side (actually resting on the main wiring harness) and form the other end of the catch can into the side of the intake mani. there's no check valve in the oil/water separator, just whatever residue oil gets filled up in the canister and whatever gets shot back into the intake mani.
04-28-2014, 02:23 PM
#15
few more info on if it may be something else. currently running ~10.8:1CR and my AFR was between 12.7-13.0(hit 13.0 for a couple seconds at the start but stayed around the 12.7 range majority of time), timing at 28-29* and virtually no KR (have a portable scanner that reads KR) on 93oct. would any of that have an effect on whats going on or is it mainly overpressure in the crankcase?
04-28-2014, 03:05 PM
#16
thinking back a bit, would only having one side of the engine to relief the pressure be enough or create a bottleneck(in this case driver side)? whereas before the throttlebody swap the original one had a vac port to help relieve the pressure on the passenger valve cover port?
04-28-2014, 05:35 PM
#17
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i'm just hoping it didnt crack a ringland..... but i think i did. havent done a compression test or leakdown test yet but i want to try and diagnose everything else before i do that (or have my buddy do it). i just dont understand how there's too much crankcase pressure even even with the pcv setup im using
edit-and i noticed when i pooped the hood the dipstick popped up a bit too unfortunately. cant recall if any oil was on it or not or if the oil erupted from only the pcv port on drivers' side.
but i think i did. havent done a compression test or leakdown test yet but i want to try and diagnose everything else before i do that (or have my buddy do it). i just dont understand how there's too much crankcase pressure even even with the pcv setup im using edit-and i noticed when i pooped the hood the dipstick popped up a bit too unfortunately. cant recall if any oil was on it or not or if the oil erupted from only the pcv port on drivers' side.
long story short I stroked and forged it...
Hope your outcome is better...
04-28-2014, 07:29 PM
#19
If the PCV is the only engine vent, it will blow the PCV out during high rpms everytime. You need to have some sort of breather on that thing! You might start pushing the front and rear seal out if you keep driving it. At least take the cap off of your other valve cover and let it just vent with a hose going in a loop. Best thing would be to connect it back to the intake tube.
