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valve cover
https://www.slantsix.org/forum/viewtopic.php?t=12040		 Page 1 of 2
Author:  oibrownskin [ Wed Mar 02, 2005 12:36 pm ]
Post subject:  valve cover
I have a problem, and with some more cash (not substantial, but more) coming in I am looking to solve it. I recently converted my 1966 slant six 255ci to dual weber carbs. the problem is this:
My original stock setup had the closed loop crankcase ventilation. This meant that one hose ran from the valve cover to the base of the carb, and one hose ran from the oil breather/oil cap to the air cleaner on top of the carb. Now my setup, has the hose from the valve on the valve cover to the intake manifold (same function as the hose to base of carb in stock), but now the oil cap/breather cap is open to atmosphere. There is no setup to vent it directly to the air cleaner. I am getting TONS of oil mist when I drive, and it is getting all over everything, and getting my air cleaners VERY dirty to boot.

When I changed my valve cover gasket not too long ago, I noticed that the "baffle" had a LARGE gap between it and the top of the valve cover at the opening to the oil breather/cap inlet. I have noticed on other true baffled valve covers, that gap is very, very small and tight. I have read in articles (from mopar action) where in a rebuild they took valve covers and with a body hammer, gently tapped or beat the baffle closer the to top of the valve cover to reduce this gap.

I am tired of having oil mist everywhere (if it were smoke people would think my car is on fire). What are my options? I am leaning toward buying a new valve cover that was either designed for the open crankcase ventilation, or a new aftermarket valve cover from Clifford.

What to do?
Sorry for the length, and thanks for your time,
Caesar
Author:  Dennis Weaver [ Wed Mar 02, 2005 12:49 pm ]
Post subject: 
Sounds to me like your problem is pressure inthe crankcase, likely from worn rings. That is, if you have a functioning PCV as you say you do. Whether the oil breather is routed to the air cleaner or not is irrellevant to your oil mist problem.

D/W
Author:  DusterMunster [ Wed Mar 02, 2005 1:06 pm ]
Post subject: 
I have a similar problem, I mean it is more simple and different, but similar though... every time I stop the engine ('74), there is some kind of graysh smoke coming out of the air filter housing... I checked and it cames from the crankcase inlet filter through the hose; it keeps coming out slowly for over an hour after the engine is turned off. Sometimes when I start the engine and suddenly stalls by itself with some sort of explotion just after cranking, the engine bay gets filled (and no kidding, FILLED) with a very dense smoke coming out the same place... I keep cleaning the engine from oil mist, particularily in the surrounds of the PCV valve. I think it works, you can hear the rattle on it and there is vaccum in the line. This problem is making me change the air filter a lot, because it gets really dirty and oily pretty quick. What should be the problem?
Author:  Eric W [ Wed Mar 02, 2005 1:35 pm ]
Post subject: 
Welcome to the world of shot piston rings. The amount of blow-by over powers the pcv, so the gasses have to go someplace...and that is the breather cap (that is supposed to filter air coming into the crank when the pcv sucks it out). Been there, done that, put a lower mile engine in! :mrgreen:
Author:  DusterMunster [ Wed Mar 02, 2005 1:45 pm ]
Post subject: 
Thanks Eric... I was afraid that was the problem :cry:

Would it also has something to do with some valve problem?

Ed
Author:  Super6 [ Wed Mar 02, 2005 2:10 pm ]
Post subject: 
Non-environmentally friendly solution (temporary, the real cure is new rings/rebuild :( ) : Use a closed system style breather (one with teh nipple for a hose) and run the hose either (1) down low enough to expel the mist below the engine compartment or (2) run the hose to a container (like an empty oil-quart) packed with foam/cotton/etc. Be sure to cut a few vent holes in the container.

The packing will absorb most of the oil mist, and still allow the crankcase to breathe. The container/packing will need replacement every few weeks +/-, depending on the severity of the blow-by.

I did the container method (with a 1 liter plastic pepsi bottle) for ~6 months many years ago, when the slant was bone-stock. Saved me from having to buy a new aircleaner every 3 days. I ended up replacing the packing in the bottle about once a month. It's not pretty, but it works. :?

-S/6
Author:  DusterMunster [ Wed Mar 02, 2005 2:17 pm ]
Post subject: 
Thanks, will try the "Coke solution" (I hate Pepsi) temporarily. But I think I should start saving some $$$ for the overhaul.

Ed
Author:  LASwinger70 [ Wed Mar 02, 2005 6:50 pm ]
Post subject: 
Hmmm, I also have this problem, and honestly it did not start until after I put on my weber, I had to make my own pvc connection in my adapter and I wonder if I have too much vacuum going to my pvc. With my hose that went from the breather to the air cleaner, I just put some blue shop cloth in it to act as a filter (My breather has a second hose which attaches to a line which runs to the fuel tank).

My compression and oil pressure is very very strong, I do not believe I have a ring problem.

Oilbrown, please post what your solution is.
Author:  argentina-slantsixer [ Wed Mar 02, 2005 7:02 pm ]
Post subject: 
I had this very same problems with either too large PCV holes at carb or too small. I ended up puttin a resttrictive piece of lined delrin on my holley 1922 (argentina version of a 1920) ending up in 4.5mm internal bore at the carb end. Cured all my troubles. Another thing you may wanna try especially with webers is fixed PCV hole. according to some specs that I don't know where I got, it's .085mm per each 100cc so that will be like 1/8" hole at the PCV valvle end. You can build a fixed system permamently open with a 1/8" hose, that would do it. I've tried this solution with frankestein carbureted slants and seems to work just fine for me.
Author:  argentina-slantsixer [ Wed Mar 02, 2005 7:04 pm ]
Post subject: 
or simply remove the check ball on your PCV, fix the hole at 1/8" and run vacuum line inside the regular PCV hose.
Author:  74W100/6 [ Fri Mar 04, 2005 12:43 pm ]
Post subject:  Exhuast recirc valve
So if im gettin alot of smoke billowing out of my recirc valve thingy that hooks up to my air cleaner housing would you suggest i have blown rings?
Author:  Rust collector [ Fri Mar 04, 2005 12:48 pm ]
Post subject: 
Probably.
Some is normal, but a lot is bad
It is hard telling you how much normal is, from here...
Author:  argentina-slantsixer [ Fri Mar 04, 2005 1:23 pm ]
Post subject: 
if your carb is extremely bad jetted (way too rich) you could be experiencing rings wash out (I don't know if you guys call this way to excessively rich mixture "washing" the oild from the rings, increasing blowby, we call that this way down here) that would increase your blowby at first non permanently, but it ends with shot rings for sure.
Author:  SlantSixDan [ Fri Mar 04, 2005 1:42 pm ]
Post subject: 
Quote:
Now my setup, has the hose from the valve on the valve cover to the intake manifold
Just one question: Exactly where on the intake manifold is the PCV hose connected?
Author:  cranky265 [ Sun Mar 06, 2005 5:20 pm ]
Post subject:  PVC fix ...
I came across a similar problem on my Hemi 265 with an after market valve cover which had no internal baffle, which inturn led to my PCV dumping oil in the manifold. I magaged to fix it my installing an oil separator type breather before the PCV. The PVC valve was a aftermarket replacement which had a 90deg plastic elbow wich made it easy to remove the elbow and run it inline with the hosing. The only real modification was that the old PCV hole on the valve cover needed to be inlarged to accept the new breather.
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