Home to the frozen chosen, where the current temp is -10. GM has had an issue with their 2.4 Eco Tec engines pcv system. Instead of an actual valve, they have a small, 1/16" hole in the intake manifold which is used to regulate crankcase ventilation. The problem is if condensation builds up in the upper air box and this 1/16" hole gets plugged off, pressure build up in the crankcase and in many cases causes the rear main seal to leak, sometimes a little, sometimes - if it blows out - catastrophic oil loss.
My question is if we plug off the pcv system, won't this cause the crankcase to pressurize and create oil leaks, some little, some big! I know I had this problem years ago and had to unplug the pcv system for a customer due to a newly created oil leak. Once I unplugged the pcv, the oil leak stopped.
Open up the diameter of the hole/hoses? If vapours cool and collect (freeze, no doubt in some cases) and block how pressures flow, maybe giving them more room to work with/through might help?
I opened up my 3/8 or 5/16” PCV to 3/4” (go big or go home, right?) and the buttery goo that used to collect in cooler weather under the oil fill cap of my ride all but disappeared.
Greg Kusiak
Most Active Member
Audiophile
The following user(s) said Thank You: Ron Hatton, CLAUDIO CORDOVA
All hoses in the PCV system reroute T, breather included.
In my case, the ports were able to accept a much larger ID hose/fitting easily.
My GM engine also doesn’t have a PCV valve, like the one Scott mentioned. It was simply an orifice on the manifold with that plastic/nylon hose and a right angle fitting (That right angle fitting is still used for the MAP sensor relocation) with the other end connected to a barb on the nearest valve cover. The port on the other valve cover, the back of the engine near the firewall (V6) accepted a right angle fitting for the breather (the factory fitting always seemed to pop out).
I don’t know the engine Scott has mentioned, but if the intake manifold is plastic (as many are of late), it seems to me an easy fix would be to remove it, enlarge the orifice on both it and the air box, and use a larger diameter hose when reconnecting them.
Maybe I’m missing something: Scott, you’re saying there’s a connection between the air box and the intake manifold AROUND the TB? A massive factory vacuum leak?
IScott- does this engine have a crankcase breather hose/fitting for the crankcase? Point is, if the manifold vac. source- the small hole- is blocked off, then can't the crankcase vent any pressure thru the breather hose.? There HAS to be a breather setup to allow fresh makeup air in. Or did GM do something real weird on this one?
Tracy
Tracy Gallaway
Founder and Constant Aide to Gadgetman
Gadgetman Reno, NV
This thread dovetails nicely with the door Ron kicked open this morning with his newsletter about crankcase vapours in the cold in relation to our Groove.
by defeating the factory PCV system on engines we groove, we expose ourselves to these potential situations, so we really should have a method to offset the negative potentials - and if we can turn them into positives, we look more like stars/geniuses especially if it enhances the effect of the groove.and prevents any engine damage.
This time of year, the vapours/blowby condense quickly because what they travel through is cold, can get frozen/plugged and cause big problems like Scott describes at the beginning of this thread. If we can find a way to reduce the vapours, and reduce the amount they cool/condense, we may be able to avoid those big problems entirely.
I came across this video in my YouTube feed a while ago:
I found it particularly interesting that
1- by venting the steam into the passive side of the intake, vacuum increased, and
2- water vapour at the tailpipe seemed to disappear.
Putting these things together, it seems to me an engine runs better with some water vapour in the intake airstream, but we have to be concerned with TOO MUCH building up in the crankcase.
So here's my idea for discusssion:
add an air-oil seperator to our PCV re-route to get the water vapour and combustion crud out of the crankcase, and then use either heat from exhaust or engine coolant to turn that stuff into steam that gets re-introduced into the intake (for efficiency and/or enviromnental regulations) upstream of the TB, and not interfering with or reducing manifold vacuum. TracyG has found a BMW-made unit that worked brilliantly on my car to get the moisture to condense, but the issue I had was that the catch bottle I used filled up quickly...think a pint of liquid (500mL) every 600 miles (1000km). What I could've done is, rather than collecting the vapours, send them near/through an existing heat source (like extending the exit tube from the BMW cyclone unit with copper pipe wrapped around the exhaust manifold), and then vent the steam back into the intake between the MAF and TB. another option is to T-connect the output into the EGR system if possible, (which would help that valve from carboning up, make it work more effectively/longer).
What do y'all think?
Greg Kusiak
Most Active Member
Audiophile
The following user(s) said Thank You: CLAUDIO CORDOVA, Preston
Further, getting back to condensed blowby vapours, we have summertime operations to consider as well. perhaps what I suggested above will work when it's above freezing, but for those who don't have to contend with freezing weather (I envy you, equator dwellers!), you could collect the condensed blowby in a catchcan and then bubble it into your intake for water injection:
in one of that explorer/inventor/creator's videos (or the comments), he talks about having to mess with oxygen sensors. I've mentioned EFIEs before, and you should really google them. Ron hasn't posted anything lately about what he's got going on with OBD2 computer stuff, but until something comes of that, we have EFIEs and MAP enhancer circuitry...more weapons in our arsenal against big oil and global warming.
I remember seeing this venturi water introduction video years ago and tried it. Didnt work for me.
Also there are some of these videos in the archives and other members have tried it with no success.
Maybe its just some models it works on or maybe application is the key.
The steam intro I haven't seen before and would be great if this was successful.
Have seen other devices that introduced exhaust gas back into engine supposedly with success and was being marketed
but the exhaust gas was also fed into a metal box that rested on exhaust manifold in order to reheat.
Ron started an EGR thread...check into it and add your input please.
But more importantly, TRY some of these things and report back here. maybe someone knows how to make it work for YOU in/on YOUR application.
Greg,
Here is what I found in the archives on the venturi vapor application.
The site would not allow me to send the link in the post so just look up "water injection" in the search box and you should get the video you posted
from a post from December 2016. Hope this works.