I've been thinking about how to get maximum ventilation from the crank area on my 59AB. I made this to fit the intake I'm going to use after break-in. First pic is with the the air supply****embled. Here is the intake baffle installed. It is a 1 3/4 dia. piece of exhaust pipe inserted into the block valley opening where the fuel pump pushrod is located. I turned down the bottom end of the pipe to 1.712" to fit into the opening in the valley and machined the length so that it's held in place against the gasket that seals the base of the fuel pump stand. Finished product. The air is pulled into the engine and goes through the crank area and comes back into the lifter valley through the oil drain holes above the cam. A PCV valve installed into the front of intake casting is connected to vacuum under the carb. Well; what do you think?
Just like Henry did it, except you left out the internal swirl baffles. Actually, the top had an edge that sat on the gasket too.
Does the Original system do it fine by drawing air in the oil fill cap and then out through the drain pan vent?
All I ever used on a 59AB was the stock style ventilation system. Seemed to work fine? I have done several 8BA motors with intakes built by Baxter Ford Parts that used a PCV setup.
I ran a pcv system. I plugged the pan vent with a freeze plug at the top of the tube. The Offy intake had a place open so I put a sbc valve in the hole with a grommet. It was plumbed to the wcfb base. I put a small paper filter on top of the fuel pump stand. I think it worked fine. No drips.
I think it did work well enough when there was enough air flow past the pan opening ( or tube for 8ba).I am hoping for a more continuous function.
You did a nice job, but get the real part so it fits and the flange seals the gasket surface. cheap and easy.
On a 59x style engine (any 24 stud for that matter and most 21 stud engines after the mid-30's), the fresh air supply was the back of the engine (through the fuel-pump stand). The air went DOWN into the crankcase (due to having the baffle I show up above), then the air could come back up into the valley area and was pulled out by a road-draft pan-vent on the front of the oil pan. I question how well these pan-vents actually worked . . . seems they were best for "chassis lubrication" - LOL. On factory 49-53 engines the fresh air supply was moved to the forward part of the intake and the newly added "road draft tube"*****ed the combustion gasses, water vapor, etc from the front pipe in the valley area. The biggest problem is that on MANY 59X engines, the rear baffle is missing (guys just threw them out when they put aftermarket manifolds on them). When the baffle is missing, the air is NOT being directed down into the crankcase.
Thanks@Bored&Stroked for the pictures. Do you think the tube,without the helical baffle, would work as well? I'm going to make another for the stock intake for break- in and until I can more than yard drive the truck.
I just had another thought; the baffle may be more to direct oil into the crankcase than air. (when changing or just adding oil).
I would think with all the cracked blocks around there would be some extra vent tubes in the world. I probably have one, I'll look if I get time today
The only thing the helical baffles accomplished was a way to capture oil vapor and for it to drip back into the crankcase. We've all seen plenty of flatheads (while idling) where you could see some blow-by coming out the breather tube. I can see no reason why your method shouldn't work well - especially if you had a PCV to put positive crankcase vacuum into the system - even while you're not going down the road.
Thanks for a good explanation of the function of the stock system. The humorous part of this, to me, is that since the baffle was missing in in my 59AB I****umed there wasn't anything there in the first place. I had looked at the blowup in my Green Book and there seemed to be only the fuel pump stand. The 6756 part is in the parts list, but not on the blowup page.
I would thing Fred at Southside Obsolete @barnfind08 would have an NOS or perfectly used one for sale as well.
Not sure he has one or is planning on one . . . though they are a good idea if you are up for a little fabrication (depending on the year of the block, manifold style, etc).
And now for the rest of the story. I called V8Bob to see if he had a baffle because he has a lot of flathead parts, but mostly 8ba. He had previously told me that military vehicles during WWII had PCV systems on their flatheads . He thought I was looking for that part. When I said that I was looking for just the baffle that went under the fuel pump stand, he said " I might have one". He did. No, I didn't think of them. I have one now. I have a valve. I got it from my local NAPA store. I think it is for a Chevy 262 v8 and/or 4.3 v6. I picked the 262 because similar size and relatively long stroke and small bore.
Just make sure that the particular PCV valve that you selected is designed to be mounted in the same orientation you plan to use.
I remove the oil pan vent and weld a flat plate with a pipe 1/2 coupling in place. pvc in the tube from the pipe to the intake. Works great and engine does not leak-negative crankcase pressure then. Newc
This is where I mounted mine. I also pushed a small piece of open cell foam into the draft opening at the front corner of the oil pan. Works very well with no oil misting from the rear air intake/oil fill tube. https://www.fordbarn.com/forum/showpost.php?p=1935882&postcount=105
Here is the PCV mounting on the stock manifold. I'm breaking in the engine with one carb. I may get more creative with the plumbing on the Super Dual.
Hi Joel, your system looks like it will work great. But since you asked the question I thought I would post up this section from my old build thread just for the sake of conversation. This system has been working fine in my coupe for a few thousand miles. The thread covers some of the stuff mentioned in comments on this thread so I hope it may helpful to others that are considering this modification. Sam Crankcase ventilation is today's subject. I wanted to change the ventilation system from the stock passive or draft tube style to a more modern PCV system. This is a kind of oversimplified drawing of the stock system used on the 59 series engines. Air was*****ed into the engine at the air breather at the back of the engine on the same pedestal the fuel pump was attached to. The crankcase blow by gases would then find there way out of the the cam gallery through a steel tube near the the front right corner of the block and pass through a cavity in the block and finally out to atmosphere through a hole in the oil pan. I wanted to use the more modern system as shown in this Overhead V8 drawing. So I modified my flathead's system by putting a plug in the cam gallery draft tube and installing a PCV in the front of the intake manifold. I also plugged the hole in the oil pan. I am using speedways four barrel intake manifold. I have had this intake for 4 years and have not seen one on a driven flathead yet..... I hope the darn thing works OK.I know it is not traditional but Uncle Mike wanted a four barrel carberator and this one looked like a better choice than the Edelbrock or Offenhauser intakes. The intake is a beautiful 2 piece casting. My main complaint about this manifold and possibly one of the reasons you don't see any of them is that they do not include the flanges needed for the openings at the front and rear of the intake for the breather and or PCV valve.I asked Speedway if they had any thing to fit the openings and they said no and after further questioning they said they did not have any plans to make any either. I mentioned that they had produced an incomplete product and that I didn't think most people would be willing to fabricate the flanges required to use the manifold. Well I guess it wasn't the tech guys problem.... I still don't see any flanges offered in their catalog. I had to make both flanges. I designed this part for the breather on the back.I cut it out 1/2" aluminum scrap and then attached it to the face plate on my old lathe for some machining. A trial fit of the breather. The finished part. This breather provides the intake air for crankcase. I can't resist polishing aluminum..... This is the lifter valley intake for the draft tube that vents the crankcase. You can see the plug press fit into the top of the tube. I left the whole pipe in there so oil would not run out of the crankcase into the cavity that leads to the outlet on the oil pan flange. I machined the plug out of 1/2 aluminum to a pressed fit A little ultra black silicone was applied to ensure a seal. This is the draft tube outlet in the oil pan. I made a steel plug for it too so moisture wont sneak up into the block. Probably was an unnecessary step. Tacked. Finished . Up front I had to make another plate to hold the PCV valve I used an aluminum type valve cover grommet to receive the PCV Valve. The PCV valve is plumbed to a vacuum source in the carburetor adapter plate on the intake manifold. So that's the crank case evacuation system. Once again let me say the engine has not been run yet so I don't know how well this system will work. I think it should work OK on this little engine if it works on the larger overhead engines of the 60's and 70's. I will be sure to post the results once I get the engine running.
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