Valve covers/ PCV

MMNineInchNails · #1 (**permalink**) 11-22-03, 06:35 PM

I got some chrome valve covers for the caddy, but they don't have extra holes for the PCV. Each valve cover has ONE hole for an oil cap, so how could I put these on and not screw up my engine by not having the PCV on there? I was reading up on PCV (positive crankcase ventilation) and you can really mess up your engine if you don't have it because the oil turns to sludge and such and it wears down everything faster.

DaveSmed · #2 (**permalink**) 11-22-03, 10:48 PM

Not just sludge, but with the blow-by gases, pressure builds up in the crankcase and blows all of your gaskets out. Anyway, You could look into a nice chrome breather assembly, or use a breather on one valve cover and reuse your old PCV valve and grommet on the other. Either way, it looks like some drilling is necessary. What size are the cutouts for the oil caps?

MMNineInchNails · #3 (**permalink**) 11-23-03, 02:23 AM

the diameter of the holes are about an inch and a half.

MMNineInchNails · #4 (**permalink**) 11-23-03, 02:25 AM

My friend said I'd be alright if i put one of those mini air filter looking things in one of the holes, and the other put the oil cap in. Would that work? There would be no hoses going to the carburetor though, it'd just come from out of the valve cover to the filter then no more connection to anything.
thanks for the help

davesdeville · #5 (**permalink**) 11-23-03, 04:29 AM

The PCV valve connects to the valve cover on the pass. side of the engine (in my 425 anyway, I assume yours is the same) and there's a hose that runs to the carb. Then there's a filter on the other valve cover. These both need to be there for the system to work.

hybrid2nr · #6 (**permalink**) 11-23-03, 02:27 PM

The carburetor idle and low speed power systems are designed and calibrated to work in conjunction with the PCV valve system hooked up correctly and in good working order.

If you consider the PCV valve as a calibrated vacuum "leak", you can see why the idle speed and mixture changes when you remove and plug the PCV valve with your fingertip. The crankcase filter in the air cleaner should be clean and is the inlet to the crankcase from which the PCV valve draws any gas and oil fumes, water vapor, and blowby gasses. Water vapor combines with oil to form sludge and blowby gasses are the primary contributor to the formation of acids.

The check valve within the PCV valve is merely a backfire check valve to prevent crankcase explosions. Many modern PCV systems no longer use a valve, but use an orifice without the check valve feature instead. Since they no longer use engine-mounted mechanical fuel pumps, the likelihood of raw gas leaking into the crankcase from ruptured fuel pump diaphrams no longer exists. On top of that, OBDII systems will shut off the fuel injector on dead cylinder(s) anyway.

MMNineInchNails · #7 (**permalink**) 11-23-03, 02:45 PM

Ok I'll explain this in more depth.

On my passenger side valve cover, there is the PCV valve out of the valve cover and the oil cap. On my Drivers side valve cover, there is just that hole that you plug that thing in that goes into the airfiter (I don' know what it's called). And that's all. So I don't have a filter on that side.

I'm also putting on an edelbrock 750cfm so The crapajet is off. I need to get an inlet so I can hook up the brake booster too.

My question was could I put a filter on one of the valve covers instead of the PCV valve and then have the oil cap on the other valve cover?

Basically is there a way to bypass the PCV and have it still take out that crap so the oil wont turn to sludge and not have to hook anything up to the carb and use my chrome valve covers?

100 · #8 (**permalink**) 11-23-03, 03:13 PM

Maybe you got 2 of same side covers by mistake??
(I know you should have the oil cap hole and PCV
on the same side cover though...)

DEEVEE8 · #9 (**permalink**) 03-12-04, 10:07 AM

Quote:

Originally Posted by MMNineInchNails

Ok I'll explain this in more depth.

On my passenger side valve cover, there is the PCV valve out of the valve cover and the oil cap. On my Drivers side valve cover, there is just that hole that you plug that thing in that goes into the airfiter (I don' know what it's called). And that's all. So I don't have a filter on that side.

I'm also putting on an edelbrock 750cfm so The crapajet is off. I need to get an inlet so I can hook up the brake booster too.

My question was could I put a filter on one of the valve covers instead of the PCV valve and then have the oil cap on the other valve cover?

Basically is there a way to bypass the PCV and have it still take out that crap so the oil wont turn to sludge and not have to hook anything up to the carb and use my chrome valve covers?

Your edelbrock should have a port for the brake booster, it may be on the opposite end however. Add more hose and an elbow or two.
Put your filter on one valve cover and the cap on the other. Change your oil when your supposed to. Live happy. (and occasionally wipe the area around the filter off, it will accumulate an oil film/rust preventative)

Or...

Leave the filter off. Use something creative to make a turn downward from the valve cover and then put a piece of tubing or rubber hose (like heater core hose or similar) on it and route it down towards the bottom of the car. Mine lays across the transmission and off the other side and points toward the road. This is called a "road draft tube", it was perhaps the first "emissions control" in the most primitive sense. The principle was that when the car is in motion the draft (suction) of air across the hose from underneath would evacuate the crankcase and prevent the formation of sludge. Works too. Only in the 60's did the treehuggers decide that we should put that stuff through the engine first before releasing it to the atmosphere.

DEEVEE8

DaveSmed · #10 (**permalink**) 03-16-04, 02:03 AM

Very old school emissions. Remember the brown stripe down the roadway from those things?

lux hauler · #11 (**permalink**) 03-16-04, 11:00 PM

PCV on one side and breather on the other side.......that's all you need. No need for a filler cap.

MMNineInchNails · #12 (**permalink**) 03-17-04, 12:37 AM

Yes yes i know i found out way back when i first posted this. Why are people still talking about it?

DEEVEE8 · #13 (**permalink**) 03-17-04, 04:49 PM

Quote:

Originally Posted by MMNineInchNails

Yes yes i know i found out way back when i first posted this. Why are people still talking about it?

Well, son, its like this. When you post a thread, you are throwing out a topic for discussion. It is being discussed - it's not just to answer your question. How's the transmission removal comin?

DEEVEE8

MMNineInchNails · #14 (**permalink**) 03-17-04, 09:07 PM

Quote:

Originally Posted by DEEVEE8

Well, son, its like this. When you post a thread, you are throwing out a topic for discussion. It is being discussed - it's not just to answer your question. How's the transmission removal comin?

DEEVEE8

shitty. No lab time. i have the old one out i have to put the new one in.