MOTOR, Flathead PCV

[Petejoe]

I can remember some very good ideas given in past posts regarding installation of PCV valves on the flathead engine.
I thought I saved it but can't find it in any of my Hamb material or the Techomatic. Has anyone saved this?
It would be great to post it here so that we can techomatic it. I think it fell through the cracks a while back.

[Digger_Dave]

Petejoe, there WAS a great piece on PVC's for flatheads. (may have been more than one)

I lost it when I had a major computer "meltdown."

To help "jog" memories; the valve was mounted INSIDE the valve galley, on the underside of the manifold. (whoever posted it, supplied some excellent pictures)

The whole setup was out of sight.

[Fourdy]

Not saying this is the only way, but if interested you might check my webshots to see how I put the pvc under the manifold. Sorry, don't know how to post the pics here.

http://community.webshots.com/user/fourdy

Fourdy http://www.jalopyjournal.com/ubbthreads/images/graemlins/ooo.gif

[Digger_Dave]

Thanks Fourdy, THAT'S THE ONE!
How about a TECH artical on how you did it?

[Fourdy]

Thanks guys. I'll do my best at this. My block is a 49-53 with early heads and blocked intake manifold. (oil fill and road draft tube) I used the early oil fill tube at the back of the block.

Cut the tube that comes up from the floor of the valve valley shorter by about a 1/2" or so just to make sure it will fit under the intake. Weld on a cap. Drill the tube and fit a smaller tube about the size of the snout on the pcv. I made mine about 3" long so I wouldn't have to worry about the rubber tube coming off. Since these pics were taken, I replaced the 90 degree square fitting with a one piece 90 elbow with a short nipple connecting to the bottom of the intake to get it below the gasket. (Cut a hole in the gasket for the nipple to go through) The tubing is a high quality oil hose that you can find at your parts stores. The PCV is a Borg Warner PCV255. It has the proper directioned check valve.

I'll try some pics. Let me know if there is anything else I can help with and thanks for looking.

Fourdy http://www.jalopyjournal.com/ubbthreads/images/graemlins/grin.gif

[Fourdy]

another

[Fourdy]

another one

[Fourdy]

Last one. Hope these aren't too big or cause anyone any trouble.

Fourdy

[MattStrube]

So, does the fitting in the intake go into one of the runners and the rubber hose connects the pcv valve to the oil fill tube doohicky? matt

[Petejoe]

Thanks Fourdy! Thats a great techomatic job.
There also was others which had different installations.
Anyone have it stuff away?

[modernbeat]

I posted a couple shots of a killer pcv setup for a flathead. A quick search turned up this old post. (http://www.jalopyjournal.com/ubbthreads/showflat.php?Cat=&Board=UBB1&Number=100835&Forum=A ll_Forums&Words=valve&Match=Entire%20Phrase&Search page=0&Limit=25&Old=allposts&Main=99824&Search=tru e#Post100835)

[Petejoe]

Thanks Modernbeat!
I am going to copy that post onto this reply,
Trying to keep them together then may Ryan will put into the techomatic.

zonkola
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Breathers & virgin valve covers
#99824 - 06/30/03 10:43 PM Edit Reply Quote
I'm guessing I'm not the only guy here who'd rather not punch any breather holes in those nifty vintage valve covers. I could do either PCV or not, and I'm starting to have strange thoughts involving drilling holes in the intake manifold and maybe fabbing an oil fill tube/breather in place of the mechanical fuel pump block-off plate.

Short of going all the way back to draft tubes, what have you done that works?

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Re: Breathers & virgin valve covers
#99828 - 06/30/03 10:45 PM Edit
Zonkola
What kinda motor do you have?

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zonkola
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Re: Breathers & virgin valve covers
#99840 - 06/30/03 10:55 PM Edit Reply Quote
It's a Ford 289, but I figure most any creative breather trick that works on an OHV V8 could probably be made to work on a SBF as well...

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PakRat32
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Re: Breathers & virgin valve covers
#99844 - 06/30/03 11:00 PM Edit Reply Quote
I'm not sure what ford did for road draft tubes..
But on my 283 i used the stock breather they used under the intake for the tube, drilled a soft plug that fit the road draft tube hole for a grommit and stuck a pcv valve there.
It's right behind the dizzy so you can't even see it.
Now i know there's guy's that say trad cars didn't have pcv valves, but i have one with and one without.
Neither car has a hood and the one without just has the oil fill tube in front, well that acts as the damn draft tube and spits oil all over the firewall and cab of the truck when yer really rollin.
I have also seen a hole drilled in the rear of the intake, with a shield made as a baffle to block oil from being sucked up, tigged to the underside of the intake.It worked for my friend.
hope this helps a little.
Rat

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jaded42
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Re: Breathers & virgin valve covers
#99863 - 06/30/03 11:27 PM Edit Reply Quote
My brother runs a 302 Ford in his current hot rod. (1965 Mustang) He put on those Edelbrock valve covers with the fins and they had no breather holes. He put a set of aluminum valve cover spacers under the valve covers painted the same blue as the motor. He drilled holes and instaled some tubes for 5/16 fuel line hose. One hose runs to the bottom of the air cleaner and the other hangs down in back of the head with a small breather on the end out of sight. The spacers let him use the valve covers and the hoses arent that obvious. He has a four barrel Holley on it with a chrome round air cleaner. Looks good and works for him!
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zonkola
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Re: Breathers & virgin valve covers
#99883 - 06/30/03 11:49 PM Edit Reply Quote
PakRat - Your 283 PCV setup sounds familiar. Ford did a similar thing to the early SBFs when they moved away from draft tubes. Bolted up to the same fitting (on the intake manifold in this case) and everything. Drilling a hole in the rear of the intake (aftermarket Edelbrock) for a PCV valve fitting is one of the ideas I'm considering.

Jaded - I dig the valve cover spacer trick. Can't use it 'cause I won't be using spacers, but it's a nifty idea...

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jaded42
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Re: Breathers & virgin valve covers
#100075 - 07/01/03 10:00 AM Edit Reply Quote
Note: I called my brother last night and mentioned the valve cover spacer trick. He said to make sure if you do it to run the tube into the spacer and then upwards at a 90 degree angle and angled a little. He said this helps keep too much oil from trying to go through and that baffles would be a good idea too. I know you arent using spacers but I thought I would pass on this tip in case someone wants to try it!


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Threedeuce56
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Re: Breathers & virgin valve covers
#100193 - 07/01/03 01:13 PM Edit Reply Quote
I have seen some pretty creative ideas for running a pcv including drilling out the fuel pump block off plate,on a sbc,welding a piece of pipe out of the top side of the oil pan,with a pipe and pcv.hole in the front breather/filltube on early sbc,was actually factory on early corvettes with a pcv,hope this helps.
zonkola
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Re: Breathers & virgin valve covers
#100303 - 07/01/03 03:27 PM Edit Reply Quote
Threedeuce - Fabbing a special oil fill/breather tube where the fuel pump block off is (along with a fitting for a PCV valve plumbed into the intake) is one of the setups I'm considering. Clearances might be an issue, but I think it'd actually look kind of cool.

So, I have a PCV 101 question: Most older systems I've seen include a PCV valve and a breather -- either in a valve cover or a hose attached to the air cleaner -- the idea being that the fresh air would come in through the breather and the blowby gasses would be sucked out through the PCV valve into the intake. Pretty sure it's the same principle as cutting two holes in an oil can, one for pouring and one to let air in.

But is the breather strictly necessary for the PCV to work properly?

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Roothawg
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Re: Breathers & virgin valve covers
#100466 - 07/01/03 06:22 PM Edit Reply Quote
I asked this question pertaing to the 235 not long ago.

What I did on my 283 is I took the alum intake and drill the front(where the casting was for the original fill tube) and inserted a grommet, which was glued in, pop in a pcv vale with a hose going the base of the Carter afb. Easy money.

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modernbeat
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Re: Breathers & virgin valve covers
#100835 - 07/02/03 01:57 AM Attachment (18 downloads) Edit Reply Quote
I've seen a couple flatheads done this way. The PVC plumbing is hidden underneath the intake and plumbed into the intake from the bottom. A breather is adapted, or a stock breather is used. The system is completely hidden from view and looks period from the outside.
http://www.jalopyjournal.com/ubbthreads/image_uploads/100835-PVC1.jpg http://www.jalopyjournal.com/ubbthreads/image_uploads/100836-PVC2.jpg

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modernbeat
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zonkola
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autocol
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Re: Breathers & virgin valve covers
#100862 - 07/02/03 03:29 AM Edit Reply Quote

zonkola, yes, you do need the breather to allow air intake into the cases, otherwise you'll get very little of the "V" in PCV (positive crankcase ventilation)...

on my mullet-mobile driver, it has the breather on the right rocker cover, which has a little filter in it. unfortunately, given the fairly generous cam-overlap (she's a bit of an angry beast, my driver) there's three fifths of bugger all vaccuum in the intake, which means the brakes are a bit spongy, and the breather spits oily smoke out, making a mess of my engine bay.

I'd really like to solve that problem... I'm thinking just a road draft tube out to the bottom of the car somewhere, else a catch can of some sort...

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tommy
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Re: Breathers & virgin valve covers
#100916 - 07/02/03 08:07 AM Edit Reply Quote

Here is an inline PCV valve between the carb base and tapped into the bottom of the add on breather. This breather is epoxied shut above the PCV tap so the air is sucked from the valve cover. The breather on the other cover is normal allowing freash air to enter the motor getting cross flow ventilation. One of the important functions of a PCV is to remove moisture (condensation) from the crank case. You need air FLOW to do that.

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zonkola

Quote

Another nice setup!

Has anyone fabricated a breather that bolts in place of the mechanical fuel pump block-off plate? Picture a six inch tube in an L-shape with a breather on top, and welded to a block-off plate drilled for air flow on the bottom. Assuming appropriate baffling, is there any reason why this wouldn't work?

Lots of good info in this thread. Maybe worthy of Tech-O-Matic?

[Bruce Lancaster]

If there's anyone out there who thinks this isn't traditional, I finally located partial info on an original Ford PCV on a flathead--1940 Canadian wartime version.
I had known for a long time Ford used PCV on industrial and delivery type flathead installations, but this was the first real info on hardware I have turned up.
This was a normal installation much like OEM setups used on 1962-67 cars:
Vac hose from below carbs to inline PCV (which seems to be just like a normal modern one, except made to take apart and clean) and then to the front of the intake just ahead of actual runners.
This would be easy on a stock manifold--most have a hole or at least a boss for a vac port into both runners. On Stromberg era manifolds it is usually at the center over the two rear runners, on Holley/CG manifolds it is behind and just below carb boss below the rear mounting stud. I think this tapping into both sides of the manifold is a good idea. Multicarb manifolds obviously will require some thought, and the underneath solution seems a good one.
The Canadian wartime manifolds had a nice forward oil filling point because of deep engine compartments in Bren carriers and forward control trucks for the valley connection, but a simple tapped hole through the casting would do fine.
These rigs also got a very large and serious oil bath filter on the rear oil filler point in place of the standard brillo pad in a can.
Most of these Canadian WWII engines had full flow oil filters as well, connected to enlarged rear ports just like typical doityourself conversions done now.
PCV+good filter+OEM thermostats=no sludge.

[Fourdy]

uherkillinmesmalls --

Yes, the oil tube goes from the pcv to the draft tube. The pcv is tapped into the runners.

Fourdy http://www.jalopyjournal.com/ubbthreads/images/graemlins/laugh.gif http://www.jalopyjournal.com/ubbthreads/images/graemlins/laugh.gif

[Digger_Dave]

Petejoe, ya beat me to it!! I just finished bringing that thread BTTT!! (virgin valve covers)

Between you, Bruce and the rest, this thread is now turning up some really good information.

My solution (although NOT as pretty) was when I was running my SCoT blower which created even more crankcase pressure. The manifold for the blower had the oil filler tube and the road draft tube at the front of the manifold. The filler (with a K&N filler/filter cap) remained in the stock location. The road draft tube opening was fitted with a grommet (think it was for a Chev valve cover) with a PVC valve sticking out.

The hose from the PVC valve ran to the UNDERSIDE of the air cleaner. (remember, Under boost, the manifold didn't have vacumme, it had PRESSURE!)

The four barrel carb on the top of the blower ALWAYS had vacumme.

The setup seemed to work well, although there was the faint hint of ??? just inside the air cleaner inlet.

[Kevin Lee]

Would there be any disadvantage to just putting a breather right on the side of the oil pan? I've seen it done - but I've seen a lot of things done that weren't really the greatest idea.

[Bruce Lancaster]

Lots of racing flatheads were vented thus, I suspect because round cast pistons and wide rings don't like high revs and there was lots of blowby.
The old "Technical history of the racing Flathead" article showed early ventless ('32-34 block) engines with oil pans actually bulged from crankcase pressure.
I think a crankcase vent is actually visually necessary on your modified, but it should be bolted to an un-holed pan there and the real ventilation should be upstairs.

[Digger_Dave]

[ QUOTE ]
Would there be any disadvantage to just putting a breather right on the side of the oil pan? I've seen it done - but I've seen a lot of things done that weren't really the greatest idea.

[/ QUOTE ]

Grim, back to this thread. (suggested redirecting the other here)

The first time I had the blower on my engine I mounted an oil pan breather on the side of the oil pan. (this was before I rigged the PCV setup)
I'm not sure if it was because of the blower (creating more crank case pressure) or where it happened to be mounted, but it was always "dribbling" some oil out of the breather. It was a baffled breather but the "path" out of the breather didn't seem to have much effect. Looked good, but after driving on the highway for a while there would be streaks of of oil running back along the pan.

I took it off when I changed to to the PCV setup I described earlier so "filtered" air would be drawn into the crankcase. The rear filler/filter (on the fuel pump) was removed. (used a later fuel pump tower)

Standing on my "soapbox" for a second; Flatheads are NO different than new engines, there WILL be some blow by, AND condensation does form in the crankcase, so using some form of PCV (positive crankcase ventilation) WILL make your flathead live LONGER!!

The "trick" is to use a system no one can spot easily!!

The edit was to correct my "misuse" of PVC; should be PCV! Thanks to Paul for setting me straight!!

[Digger_Dave]

[ QUOTE ]
This would be easy on a stock manifold--most have a hole or at least a boss for a vac port into both runners. On Stromberg era manifolds it is usually at the center over the two rear runners, on Holley/CG manifolds it is behind and just below carb boss below the rear mounting stud. I think this tapping into both sides of the manifold is a good idea. Multicarb manifolds obviously will require some thought, and the underneath solution seems a good one.

[/ QUOTE ]

Bruce the subject of WHERE / HOW to connect a PVC to a multicarb setup, brings up a question.

Does the PVC valve need a "signal" from the whole engine, (more than one runner) or can it be just "tapped off" one of the manifold runners?

[Bruce Lancaster]

The OEM ones I've seen all seem to go into both sides of the manifold, so that's the way I'd go. There's lots to figure out here, and I'm not going to use the rig until engine is running right without it. First trial will be on stock manifold with truck vac port for power brakes used as the hookup. The dual may well be tapped into bottom of both runners near center.

[Petejoe]

Bttt. Ryan would you consider putting this in the techomatic?

[Kevin Lee]

I've been keeping a close watch on this thread - and it will go to the Tech-o. I just don't want to cut it short.

[Bruce Lancaster]

From Ford of Canada,from the "Instructions on Maintenance and Repair of Ford Trucks Supplied to the Defence Departments of the British Commonwealth", 1941.

I'll type in Ford's own explanation on the benefits of the PCV Monday--I just realized I brought in the wrong volume.
I evolved from seeing the PCV as a nasty and unnecessary government mandate in 1962 to seeing it as a blessing now. When PCV's arrived in general use, I was just beginning to wonder why all flatheads seemed to have a ton of sludge in them and how the heck sheet metal oil baffles that had spent the last several decades in a fog of oil spray could possibly be eaten away by corrosion. Then I finally realized that water and acids from combustion gases, mixed with dirt, carbon, and whatever, and allowed to stay there because someone had removed the thermostats and filtering was poor were the causes. Bingo--you need a thermostat to keep things hot enough to gas off, a PCV to remove the vapors before they condense and combine into acids, and a good filter. Duh. This is one area in which a bit of modernization can pay off in every aspect of performance.

[Mr 42]

Grimlock
The finesse by plumbing the crankcase ventilation into the manifold is as i understand it.

1: You get a better evacuation, even when standing still and idling

2: You wont get oilmist over the bottom of the engine.

3: Recirculation of the unburnt crankcase gases, is actually the biggest environment cleaning improvment after the catalytic converter.

4 All modern cars have it so it cant be all bad ;-)



My problem is that i dont want to have a rubber hose in the liftergallery, and i guess im a bit nervous about using coppertubing also. if its harden and become brittle and break.

[Bruce Lancaster]

Yes--I think an above the manifold setup is a bit safer as well as easier to service--but they're ugly little bastards. Mine may end up just being kept carefully tucked down low, hoses along edge of head and valve lurking in shadow of generator bracket.

[Digger_Dave]

[ QUOTE ]
My problem is that i dont want to have a rubber hose in the liftergallery, and i guess im a bit nervous about using coppertubing also. if its harden and become brittle and break.

[/ QUOTE ]

The possible problem(s) of running hose or copper tubing inside the lifter galley of a hidden PCV setup on a flathead made me nervous too. So last night I did some digging in a couple of hose (industrial) catalogs. The information I found would seem to indicate "flexable hydralic hose" would work without problems. "Hard Service" hose was rated at 250 deg C. It has a braided core and has an oil resistant exterior. The fact that it has a "burst" pressure of 15,000 kg is just icing on the cake.

[tommy]

My PCV system reverses the flow of the fresh air. One of the cool old details that I first noticed about the old flathead racers was they added aluminum breathers to the oil pan. The 59A pans have a small road draft type vent. I'm guessing the racers wanted more breathing. Flatheads seem to be the only motor that they were used on the pan.
http://fototime.com/{A464F701-960A-4A50-A952-AA27EF2D54A5}/picture.JPG
I'm using one of these for the fresh air intake. They have baffles but I added a dust filter made from strips of Scotch bright.

.
http://fototime.com/{D92D97E8-2792-477E-B809-FC4156DA13ED}/picture.JPG
Here's the business end. The PCV valve is from a 1994 Isuzu Trooper V6. It's a horizontal in line valve with hose nipples on each end. It fits into a grommet in the fuel pump block off plate. I cut the inlet hose nipple off.
http://fototime.com/{11D89F9D-3868-46E6-B114-FF48E335EF83}/picture.JPG
.
http://fototime.com/{E877696F-FE59-4F34-9DC1-A56850A39ED7}/picture.JPG

The breather/oil fill needs to be sealed on top of the stand or it will just suck air down the tube(path of least resistance) Now the fresh air enters the pan through the breather passes up through the lifter gallery and gets sucked out at the fuel pump block off bringing all the blow by with it.

This particular intake has the vacuum fitting in the runner to only one cylinder. I'm thinking of drilling a new one in the plenum so it doesn't lean out the one cylinder. This is just the initial mock up but I can live with it.

[av8]

With an alternator and converted Delco HEI scheduled for the new motor in the F-1, a PCV valve fitted to the road-draft port and connected to the back of the carburetor stand won't be that much amiss. And it's all in the interest of performance/service-life improvement. http://www.jalopyjournal.com/ubbthreads/images/graemlins/smile.gif

[286merc]

I dont particularly care for hiding it under the manifold; with my luck it will guarantee a problem.
With Tommy's pan breather and fill stand method Im thinking of drilling these spacers to spread out the oil mist. Since one side will take care of 4 cylinders do you think that is enough or should I plumb for all 8?

With the 286 I'm deliberately running a bit on the rich side anyway.

[Digger_Dave]

[ QUOTE ]
Since one side will take care of 4 cylinders do you think that is enough or should I plumb for all 8?

[/ QUOTE ]

Interesting; I tried asking that question back a while ago. (Spacers)

[Digger_Dave]

I guess at this point I need a review of what we are discussing in this thread.

PCV (positive crankcase ventilation) is a method of removing "blowby" and "condensation" that forms INSIDE an engine. (am I on track so far?) Flatheads NEED help, (the "crud" that forms inside flatheads is mostly due to condensation that forms and doesn't get "boiled off.")

The way I understand PCV is; as long as there is a "strong" vacumme "signal" (for lack of a better word) the valve is held OPEN and draws "fumes" (blowby) and "condensation" and is "reintroduced" back into the incoming air/fuel mixture that winds up being burned in the cylinder(s).

To allow air to flow through the crankcase and draw off the "crap", (blowby and condensation) there has to be a point of entry. That entry point should be well filtered otherwise the incoming air flow will just introduce dust and dirt into the engine. Reason would seem to indicate that the "point of entry" (fresh clean air) should be at the OTHER (well as far away as possible) end of the engine so the incoming air will sweep the "crud" away when the PCV valve is open. (am I still on "track" up to this point??)

Now for the "sticky" part. Any engine under hard acceleration will show a "drop" (reduction?) in vaccumme "signal." Without the "signal" the PCV would close. It's a known fact that at "cruise" with only partial throttle, the vaccumme is the strongest. Which means the PCV valve would (should) be open.

If we (or I) only tap into ONE vacumme source on the intake manifold, would the PVC function correctly without upsetting multi carb balance???

[tommy]

just my uneducated opinion but I think if it's plumbed from the base of one carb or the central plenum, the additional air would homogenize into the mixture. On the Eddie Meyer the controled vacuum leak is concentrated on one intake port right above the valve. You could tie the left front barrel to the right rear barrel with a tee in the middle going to the PCV valve. That should distribute any lean condition. When they ask... just tell them it's an early NOS prototype from the 50's.

[flatoz]

Digger Dave,

I have my PCV valve set up similar to Fourdy's and it works well. I do get some 'breathing' oil out back but not a heap compaired to other flatheads I see. I took mine off the rear carb underside runner on a 2x2.

I'm real happy with it. and plan on doind the same set up on the new motor when I build it soon.

Dont know if it needs to be plumbed into both carb bases or not.

[Bruce Lancaster]

Here's the Ford of Canada write up on flathead PCV from 1941:
"All vehicles (military) incorporate a directed flow sealed crankcase ventilating system. Its purpose is to prevent contamination of the engine oil. Oil dilution is minimized. The condensation of water vapors which help to form sludge, and freeze in cold weather, blocking the oil circulation, is also minimized. When water vapor is kept out of the engine oil, the formation of rust inside of the engine is materially reduced and one of the most frequent causes of engine wear is lessened. Crankcase ventilation also tends to eliminate the collection of corrosive acids. It maintains a higher lubricating value for the oil and helps to reduce the frequency of oil changes."
A lengthy description follows.
There is a schematized picture.

It seems to show the PCV hooked into an adaptor plate under the carb, which makes sense as the big fitting on the back was probably hooked to a brake booster on most of these military trucks. The PCV (which seems to be the same design as any common modern one) mounts right near there, and the hose then goes to the forward part of the manifold right over the vent tube from the crankcase. Presumably the old vent outlet at the front of the pan is sealed.
By the way, that vent down on the pan on most early flatheads is not a pan vent--it is isolated from the pan, and actually communicates with and draws from the tube that goes up into the valley. The vent is down there, just like the later draft tube, just to put it into moving air which supplies the pull on the non-PCV system. It is the outlet on the standard system, the filter on the oil filler tube being the inlet.

[Digger_Dave]

Bruce, any way you could post a picture of the drawing?

[Bruce Lancaster]

I don't have any suitable tech to post the picture, but will try to paint a picture in prose. Some is indefinite, because the picture is a schematized cutaway, not a picture of real components in their actual locations.
Here goes:
Fitting is tapped into front of carb riser on manifold (I see now this is NOT drawn as a separate plate. It isn't shown, but I would bet money this is tapped into both risers). PCV is mounted vertically right below the tap. It is diagrammed looking just like a modern one, except made to come apart for cleaning. From here, a hose goes forward to the area beneath the generator and right above the vertical vent pipe. Actual attachment is not shown, but Canadian wartime engines have an oil filler right here and presumably this is used.
Air enters the crankcase via the rear oil filler and travels down to the pan via the pipe mounted below that. The inlet carries an oil bath filter, just like a carb filter but smaller, in place of the civilian wire mesh filter. The air from the crankcase is then sucked up past the valley baffles into the pipe to the PCV at the front of the manifold. It is not mentioned, but presumably the civilian vent at the front of the pan area is blocked to seal the system. This is, in other words, what you would find on a typical 1962-1967 American car.
I have also read that PCV systems of some sort were commonly used back into the thirties on delivery trucks and taxis and such.
Now, surely some of you Canadians or Australians know of a derelict WWII Ford truck somewhere that might have the system intact??