Valve cover breathers / PCV advice

You definitely want to keep the PCV function. You don't need to involve the air cleaner at all. Put a breather on one valve cover, and the PCV valve on the other.

As Dave said, you do not need to connect the breather to the air cleaner base. It can be vented to the atmosphere.

Manufacturers just connect them to the air cleaner base to use the air filter as a filter for the crankcase venting also. It is simpler and complies with EPA with no arguments.

So that is the simplest solution for emissions but all you need to have really is a oil fill cap that is vented to the atmosphere and has some type of a foam filter inside it to keep dust and debris from entering the valve cover.

That plumbing would work fine and if your PCV valve does not completely close at idle, most don't, then it is legal because you have a negative flow (suction into the engine) at both idle and when the throttle is open at any amount.

quote:

Originally posted by Andyuk:
I doubt it'll make any difference to your oil smoke though..... More likely you'll need to investigate valve stem seals/guides, or if you're lucky, intake leak path from the valley to the intake runner (though I'm more familiar with windsor - that may, or may not, be possible with a cleveland).

Kind regards

Andy

Funny you should mention that? As a matter of fact all cars with a pcv valve plumbed directly into the intake manifold for vacuum have the tendancy to siphon oil out of the valve cover.

Some manufacturers have relocated the pcv valves to other portions of the engine for that reason.

There is no other place to locate the valve on the Cleveland except into the valve cover.



My parents had a Granada with a 302 in it. That engine emptied the oil pan on a trip that they took. All 5 quarts.



What I would recommend is that you use some kind of an oil separator in line that has a sight glass in it.

Something like you would use on an air compressor.

That way you would be able to see what is going on at just a glance.



Certainly if you are going to "track" the car at high speed events and/or race it, and still leave the pcv valve connected to the intake manifold you MUST use the separator.

The Cleveland valve covers and head in particular retain about 3 inches of oil in the valve cover to cool the valve springs.

It raises the oil level high enough that even just the 6 inches of vacuum that the intake will pull through the crankcase at WOT will start a siphoning effect.

The glass bowl (see pictures v) creates a separator to break the continuous suction that would be created without it.


You can run open breathers (see picture below v) on the track with the required catch cans but the Cleveland is susceptible to high crankcase pressures and really needs to be positively vented.

Also consider that open breathers loose 25hp because the upper piston ring looses some of it sealing ability unless the crankcase has somewhere in the 6 to 10 inch NEGATIVE flow pressure.

quote:

MSD 8350

Another option is using a smaller / shorter distributor like the MSD 351W distributor, 8578 non-vacuum advance or the 8478 with vac advance. Your distributor 8350 is 8 15/16" and 8578/8478 is 7 7/8" tall. You need to change the gear, there are instructions on the MSD website. I use the 8578 with a 351c bronze gear and use a dropped base 14" round air filter with I think, a 4" tall KN filter and the stock engine cover fits nicely. If you have a different intake manifold it might be different.
A link to the MSD doc.. http://www.google.com/url?sa=t...vm=bv.85464276,d.eXY

Thanks guys, lots of good advice and experience there. I note the PCV of Dave's in on the right….so I may just swap to eliminate the PCV / oil carry over issue and see if the the small amount of smoke at start up transfers over to the other bank. If not, then it looks like possibly the seals… Mike Drew had a look before it was shipped and thought it may be oil carryover…but it only happened once with him and Gary Choate and does not happen on the open road.

My inlet manifold is taller than standard and the PCV is connected directly to it by cylinder 5/6. I will also look into new breathers as suggested and see how things progress.

Thanks again!

note in the pic above that the PCV vacuum source is from the base of the carb rather than an intake runner, this is important so that the crankcase evac air from the PCV hose gets distributed evenly to all cylinders via the intake plenum...

if the crankcase evac air gets directed to only certain cylinders, there's no way those cylinders can be getting the correct Air/Fuel mixture to run a long healthy life

any 3/8" vacuum tap at the carb base should be satisfactory

lean cylinders will run Hot & damage parts!

Good point,

I was wondering the same myself, it was only when I compared it with my friends later Pantera that a similar thought occurred to me… The Holley does indeed have a spare take off that was not used when the engine/fuel system was rebuilt (see picture), so I think I shall cap off the manifold connection and fit the new breather where the PCV used to be and re plumb the set up using the new breather and air filter.

Thanks again for the advice

My suggestion is to put the pcv valve in the right valve cover. Connect it to the back of the Holley. Put a clear in line "fuel filter" in line so you can see if it is siphoning oil through it.

You could also in leu of that plumb the line through an oil separator, then to the Holley. Here is a picture of the one I am going to use.

The "oil filler baffle" inside of the valve cover should be in place also. That reduces the splashing that the rocker arms throw against that area of the roof of the cover. It is a substantial amount.

Some of those "Detomaso" valve covers have been stripped internally of the baffles.

They were also originally intended for the Boss 302 and had internal drip fingers located directly over the rocker arms.

The original engineering on the car indicated they were necessary to aid in lubricating the rocker arms. I wonder how significant that is when I hear of "roller" rocker arm failures?

I'm using these. They are chromed billet aluminum. They are inexpensive and very compact and fit a Pantera pretty well or more precisely it is pretty easy to find a place to put them.

My pcv valve location works better for me on the left side of the engine with the port at the back.

I modified one valve cover for that and used a baffled grommet.

valve cover

grommet

In line fuel filter. You could put this in line for the simplest solution.

If you see oil in it there will be no more guessing as to where the engine smoke is coming from.

A closed catch can modified as a breather.

This is what the internal oil fill baffle and rocker arm drip tabs look like.

You at least NEED the baffle. I will argue in favor of the original Ford Boss drip tabs.

You can see the new baffled pcv valve grommet projecting into the valve cover. It is located in between the last two rocker arms.

This is what the outside of the cover looks like now with the original opening plugged.

It is up and out of the way near the firewall so it really doesn't need anymore detailing than this.

Here is a comparison of the 69 and 70 Boss 302 valve covers. They both have the internal drip tabs AND the oil fill baffles.

Performance Clevelands like the Boss 351 use the same set up.

The Detomaso valve cover is a Boss 302/351 valve cover with the DT logo dropped into it.

The molds are the same or nearly the same.

This quote by Pantera Doug, makes me question his "sanity"/"level of insanity" even MORE!

"The Cleveland valve covers and head in particular retain about 3 inches of oil in the valve cover to cool the valve springs".

So I wondered...How many quarts of oil would it take to fill a OEM 351 Cleveland valve cover up to a height of "3 inches"??!! & then subsequently HOW MANY quarts would be remaining in the oil pan?!

Once I get to my Top Secret, Highly Fortified, Miles beneath the surface Underground Testing lab, I will report back my undeniable, indisputable, beyond reproach test conclusions...Mark

quote:

Originally posted by 1Rocketship:
This quote by Pantera Doug, makes me question his "sanity"/"level of insanity" even MORE!

"The Cleveland valve covers and head in particular retain about 3 inches of oil in the valve cover to cool the valve springs".

So I wondered...How many quarts of oil would it take to fill a OEM 351 Cleveland valve cover up to a height of "3 inches"??!! & then subsequently HOW MANY quarts would be remaining in the oil pan?!

Once I get to my Top Secret, Highly Fortified, Miles beneath the surface Underground Testing lab, I will report back my undeniable, indisputable, beyond reproach test conclusions...Mark

This is why you check the oil level when the engine is NOT running. The oil level in the pan is designed with those considerations in mind.



Chronologically the Cleveland is after the 428cj, but not by much.

That entire engine series, the FE was introduced as a 352 in 1958. It was raced highly in NASCAR, road racing, and always was seriously drag raced so it IS a bit of a head scratcher that it took this long for Ford to realize there was an "issue"?

Some of my friends say that I am harsh. What do you call Chevy calling Ford the "numb nuts engineering department"?



Soon after the 428cj was introduced as a 1/2 year model in 1968 (model year), chronologically about late April 1968, Ford started to get complaints from dealers that they were replacing engines on warranty, because the engines had been run out of oil.

It seems that if you turn the engine over 6,000 rpm for sustained periods of time, the oil pan gets pumped dry.

That was with 4.5 qts in the pan and .5 in the filter.



There were a series of fixes. The first one was just to add an extra quart of oil in engines already in service.

Ford made a quick change in remarking or recalibrating the dipstick in production. They didn't change the part number, just remarked the stick. Still a C7AE

That was STILL problematic, i.e, owners were STILL ka-booming these things.

Next thing to do was issue a new part number dipstick to D0AE with a TWO QUART recalibration.

Now this created a little bit of a problem. They couldn't redesign the oil pan, it would be too deep, and with two extra quarts, the crankshaft was beginning to spin in the oil in the pan because of the higher level at low rpms.

This is the point at which they added a "windage tray" to the 70 and up 428cj's. It was to aid in this issue.

So if you had a pre-68 428, by this engineering change you were running the engine one quart low even though the dipstick said it was right. At one quart low, you were actually two quarts low. But wait, it gets better.

If you had a 68 or 69 428cj, the 1970 change said that engine was now 1 quart low even though it had a revised (remarked dipstick) saying it was right, and if you had a '67, like my 67 GT500 you were now TWO QUARTS low even though, yada, yada, yada, the dipstick said you were ok.

Got that?



So anyway, on all engines, you wind up with somewhere around two to three quarts of oil up in the valve covers when the engine is turning say 5,000 rpm?

Don't believe me? Put a set of clear plastic valve covers on the car and run it up to 5,000, and see where the oil is?

Now when NASCAR decided to attempt to slow the cars down, after the 429 "Shotgun" (Boss 429 in street terms) they went to the 5.7 liter displacement limits which if you were in the Ford camps meant at the time essentially a Boss 351 Cleveland.

Intitially those engines were dropping valves in competition. Running 500 miles at wide open throttle at over 7,500 rpm was showing issues with the valve train.

The fix turned out to be realively simple. Restrict the drain back holes into the oil pan and retain more oil, or more correctly just enough to submerge part of the valve spring in it, to provide a cooling effect on them. It worked.

Ford Engineering, being what it was saw this as a good idea and essentially incorporated that into production heads.

Actually all US production engines do it. It's really just how the drain backs are calibrated to the oil pan.



There is no secret at all that if you are going to run a Pantera hard, i.e., over 5,000 rpm for extended periods of time, maybe like you might see in Germany on the Autoban, a stock oil pan is suicidal.

Why? Go back and read the part about the 428cj's. If you can't remember it, write it down on your crip sheet, because it's going to be on the test.

I will allow that for you old acid head hippies that still when I say, "hey, how you doin'?", still go "huh, what Man?" Try and focus a little ok? That gets a little embarrassing?

...and Mark, where exactly did you read anywhere that I wrote, that I said I am not crazy?

I am. It's just manageable, until you bring up things like MM? Remember, just don't say, "Niagara Falls", ok?


Calling ME CRAZY is completely acceptable to me. I even agree. Just don't call me "normal", that will get me seriously pissed.

Quoting Mike Cook, ex-Pantera racer and Bonneville specialist, 'At 6000-up rpms, the valve covers of a 351-C are full. This leaves approximately 1 qt in a stock (5-quart) pan'. So I'd say each rocker holds about 2 quarts. Mike made a temporary-use plexiglas rocker cover ala Smokey Yunick for his drag race testing.

All this is because a stock pump delivers so much upstairs oil in the stock configuration, and the drainback ports in stock heads are small with two of the 4 being convoluted and often plugged with debris. Note that only some (or none) of this may apply to aftermarket heads and blocks with modified oiling systems.