installing a pcv in my flathead.

[claybill]

just read a suer article on temperature and moisture in the tech section of the forum...

pcv's are essential to a long lasting engine...

so, does anyone know how you install or convert the draft tube to a pcv ??

bill

[oldmopar]

I always thought the breather draft tube was the same concept. Not sure how you would do it but one of the reasons I like older vehicles is none of that antipollution junk, just something that was built well enough to last 60 + years

Ed

[Plymouthy Adams]

yes..but the car must be in forward motion in order to create a shiphon effect..

[Don Coatney]

claybill;

You did not read far enough. Go to the downloads section of the main web page supporting this forum.

http://www40.addr.com/~merc583/mopar/framesets/softwareframeset.html

[greg g]

A kit is available through Vintage Power wagons. the PCV set up had been standard on military vehicles long before it became available for civilian use.

[Norm's Coupe]

A kit is available through Vintage Power wagons. the PCV set up had been standard on military vehicles long before it became available for civilian use.

And we all know government and military standards are always the best and most economical. Just think government specs for hammers, toilet seats on military aircraft and coffee pots that must be able to withstand a crash. :D :D Can't have the crew go without coffee after a crash from 30,000 feet or higher. A good cup of coffee after a crash will be the first thing they go for.

[Plymouthy Adams]

I would think fresh underwear would be the first thing they would want...

[Norm's Coupe]

I would think fresh underwear would be the first thing they would want...

Nah, they wont' need fresh underwear. The planners at the top took care of that a long time ago. Military underwear use to be government issue white when I was in. Now it's camouflage so no need for a clean pair. :D

[Don Coatney]

What is underware?

[Norm's Coupe]

What is underware?

That's the cloths you wear under your outerwear. Sort of like the socks people wear, that you don't wear. If you don't have those, you need to open your wallet and let the moths out to buy some. At the same time pick up some napkins, for the next time you go out where they only have paper towels.

[Powerhouse]

jeeez...Is this about PCVs or BVDs...hahahha:p

[RALPHDEI]

Motion isn't needed for the vent to work there is presure in the crankcase look at the vent at idle. Air gets in at the filler cap. You will need to block the vent tube, modify a filler cap to receive 3/8 hose or a pvc grommet, find a suitable vacuum at the carb or intake manifold for a 3/8 hose connection.

[Don Coatney]

Motion isn't needed for the vent to work there is presure in the crankcase look at the vent at idle. Air gets in at the filler cap. You will need to block the vent tube, modify a filler cap to receive 3/8 hose or a pvc grommet, find a suitable vacuum at the carb or intake manifold for a 3/8 hose connection.

Actually motion is needed for the draft vent tube to work. In a healthy engine there is no pressure in the crankcase. The vent tube is cut at an angle and placed near the bottom of the oil pan. As air rushes past it there is a venturi effect creating a negative pressure in the crankcase. If you have anything coming out the vent tube with the car not at speed then your engine is in need of piston rings.

For a PCV system to work correctly the vent tube should not be blocked. Instead a PCV check valve should be installed on the vent tube and this valve should be connected to the air cleaner with a sutable tube. The oil fill cap should not be modified as it is vented from the factory to allow make up air to enter the crankcase.

[Don Coatney]

That's the cloths you wear under your outerwear. Sort of like the socks people wear' date=' that you don't wear. If you don't have those, you need to open your wallet and let the moths out to buy some. At the same time pick up some napkins, for the next time you go out where they only have paper towels.[/quote']

What are moths?

[Rodger S-11]

Gents

With the flat head 1953 military version they have an metal pipe line from the draft tube out-let to an treaded tube on the in-take manifold. The one that I have looks so crude that at first I thought it was an first year High School Shop Project.

In today's pricing, there may $5.00 from any place that sells tubing and joints at an higher than normal price.

Rodger & Gabby

S-11

[Norm's Coupe]

What are moths?

[Plymouthy Adams]

I am a MOTH.....been a MOTH for years.....Man Of The House

[greg g]

Hey Don, you got your renaesance men confused. Dhe draft tube works on one of Burnuli's principals of fluids, not Sn. Venturi. The cut in the tube causes an eddy flow of air which creates the low pressure zone behind the tube, that draws the contaminated air form the crankcase. Basicall creating the same flow that in an airplane wing induces a stall. So pressure changes caused by changes in shape of flow.

Venturi has to do with pressure changes due to speed of flow.

So Sr. Venturi is necessary for gettin air in out cars and Burnulli is incharge of getting air out and flowing around the car.

[Norm's Coupe]

I think some may also be overlooking one thing about the draft tube.

A few have said you need forward movement to get air to pass the draft tube to cause it to pull the air out of the engine. As mentioned, I didn't agree with that because before I rebuilt my engine, I could see the smoke bellowing out that tube even at idle.

Now, if you still believe you need forward movement of the car to get the air out of the engine. You do have it all the time, even at idle. That's because the fan is blowing air toward the back of the car when it's idling. So, anytime the engine is running the air flows, unless you don't have the fan on the engine. So, you do have the suction all the time some were saying you need.

[Don Coatney]

Hey Don, you got your renaesance men confused. Dhe draft tube works on one of Burnuli's principals of fluids, not Sn. Venturi. The cut in the tube causes an eddy flow of air which creates the low pressure zone behind the tube, that draws the contaminated air form the crankcase. Basicall creating the same flow that in an airplane wing induces a stall. So pressure changes caused by changes in shape of flow.

Venturi has to do with pressure changes due to speed of flow.

So Sr. Venturi is necessary for gettin air in out cars and Burnulli is incharge of getting air out and flowing around the car.

I stand corrected. That Eddy Burnulli dude sure knew his flow stuff:rolleyes:

[Don Coatney]

I am a MOTH.....been a MOTH for years.....Man Of The House

Yea right...Mister two wives.... :D

[grey beard]

The MoPar factory military PCV system on my B1B came from VPW, as outlined earlier in this thread. It fits in place of the road draft tube and connects via a cast adaptor and copper tubing to a brass pcv valve, and thence into the intake - there is a pipe plug dead center below the carb that serves as the vacuum source. Cost me $65 - money well spent.

Intake air is then pulled from the air cleaner into the oil fill tube via a piece of 5/8-inch heater hose and the oil fill has a sprint-loaded flap sort of cap. What this system will do for your engine is keep air constantly moving through the crankcase, keeping condensation from collecting and causing sludge to form. I believe a good working pcv system will do more to keep enginie oil clean than any part-time bypass filter ever designed. Mine works fine. JMHO

[Ken Bartz]

Okay, I'd like to get this straight. On a good engine there is no positive crankcase pressure. The draft tube is relying on the air passing over the end of the tube to create a vacuum thus pulling out the pollutants that become air born in the crankcase. The flow is then through the oil fill cap out the draft tube.

Now you install a PCV valve and connect it from the draft tube hole to the carburetor or the intake manifold. Then you are relying on the vacuum created the intake stroke of the pistons to remove the pollutants and thus are burned in the power stroke. The PVC valve allows flow in one direction only. The flow is still through the oil fill cap then into the intake manifold and the burned up when the piston fires AND the out through the tail pipe. Right?

[TodFitch]

Okay, I'd like to get this straight. On a good engine there is no positive crankcase pressure. The draft tube is relying on the air passing over the end of the tube to create a vacuum thus pulling out the pollutants that become air born in the crankcase. The flow is then through the oil fill cap out the draft tube.

Now you install a PCV valve and connect it from the draft tube hole to the carburetor or the intake manifold. Then you are relying on the vacuum created the intake stroke of the pistons to remove the pollutants and thus are burned in the power stroke. The PVC valve allows flow in one direction only. The flow is still through the oil fill cap then into the intake manifold and the burned up when the piston fires AND the out through the tail pipe. Right?

Yes.

And you get positive crankcase ventilation all the time. Not just when you are moving at highway speeds. Actually, as I understand it, the PVC valve is not a one-way valve but a spring loaded metering valve to control the flow based on engine vacuum. Otherwise you would have high flow at idle when you don't need it as much (most blow by is when the throttle is open allowing a larger charge of fuel/air into the cylinders).

[Niel Hoback]

Ken Bartz has posted a picture of exactly what I have done except that there was a 1/2" pipe thread hole just below the carb where the wiper hose connects. I put in a tee and use it for both the pcv and the wipers. It is a good idea to try and use a pcv valve for an engine of the same c.i. displacement as it does raise the idle speed somewhat. Oddly, my 97 Buick has a 3.8 in it which is comparable to the 230 in the Plymouth.