Hi there folks. Happy Holidays and Happy New year. Have a question regarding my flathead. First here are the specs. 1950 Ford, 8BA Flathead with the draft tube removed, Edelbrock intake with holley 390 cfm 4 barrel carb. 12 volts with an alternator and where the tube went in to the intake manifold, there is a grommet and a PCV valve. Now from the valve there is a hose which Tee's off next to the carburetor . One hose goes into the side of the carb and the other goes thru the firewall and into the va***m wiper motor. Now the wipers worked fine before, or sort of, they ran slowest and slow with the turn of the knob on the dash. I was cleaning up the engine compartment of wires, etc.. and I decided to get a new PCV valve. Got a new one with a 90 degree elbow on it, then connected the hoses, shortening the hoses cause I could and it looks cleaner. So new PCV valve, nice 90 degree hose to go into the side of the carb, then shortened the hose that goes thru the wall to the va***m motor. I turned on the car and I hear a hissing sound coming from the va***m motor. I reach down there and pull the hose off and there is alot of va***m!. looks like the old PCV valve was either clogged or almost clogged. But now I turn on the wipers and the wipers go up all the way till they hit the center windshield divider and don't come down, even when I turn the knob all the way to the left and off, I have to get out and pull them down on my own. Is it too much now? Is there something stuck in the wiper mechanism or should it come down on it's own.? Thanks!! Ozzie
Ozzie, How's it going? Hope things are going well for you. You might have had a clogged PCV valve and/or the new one may be too big. Try disconnecting the PCV first - make sure your wipers work. Next, try your old PCV valve & see if they work. Just want to make sure none of the hoses got a slit in there causing a loss of vacuum. If the wipers work w/o the PCV hooked up and/or with the old PCV, you probably have too big of a PCV - I use one for a 4-cyl Ford - any late-model 2.3L engine. Let us know what's going on...
Might be a coincidence. The vacuum motor has a valve in it that reverses the direction of the "vacuum" when it sweeps all the way to each side. it might not be sweeping far enough to reverse the direction befor getting hung up on the center divider. To test, take the arm off and see if the crank sweeps properly without the arm.
I think they normally did. Or it was an option. without the dual action pump most flatties didn't have enough vacuum to work the wipers when they were accelerating or pulling a hill. I can remember letting off the gas in the 51 Merc to get the wipers to work when climbing a long hill in the rain.
you need a small valve going to the pcv so you can shut down a little of the vacuum going to it, get one from the hardware store like the ones used in a lawnmower to shut the fuel off, you only need a small amount of vacuum to the pcv and it will work fine as well as your wipers. if ya cant find one call me at 1-800-741-4687 i will send ya one free!!
If your (old) PCV were plugged, you would have more vacuum to the wipers. PCV kills vacuum by letting crankcase vapors in. I wouldn't use the same manifold connection for PCV and any vacuum users (wipers, heater controls, etc). Don't know if your 4-bbl manifold has multiple vac connections? I've got virtually the same set up on my 8BA, and am using a PCV for a 3.8L Buick; it's also a 90-degree model, Fram PCV # FV294. PCV's are sized pretty much based on the displacement of the engine, so this is a good match to an 8BA. The stock manifold (which I have) has restrictors in the holes into the manifold, in fact they are really quite small. I haven't had any problems, but may open them up to 1/8" (one into each throat of the manifold).
Do any know how to play valcuue windshielde wiper? If you guys don't know what I talking about you better ask a greybeard. It is very tradishal trust me.
Hi Folks, Sorry for the long delay, I've been working on the house. I will chnge the PCV valve to the Fram one that Albug was referring to tomorrow. But I did get the wipers to work great and here is what I did, but I think I have another issue to worry about now. I may be all wrong here but I have the PCV valve ith a 90 degree top connected via a rubber hose to a t coupler that sends one side to the side of the carburetor and the other to the inside of the car and that was connected to the wrong small ****** on the wiper motor. I connected it to the other side of the wiper motor and they now work fine.. Now It works, but I think this is basically ****ing Fumes into my p***enger compartment. I do not have a Dual action fuel pump. So I do't have any va***m being generated there. Where should I be getting the vac*** for the wipers from? My Holley 390 CFM carb has from what I can see 3 small tips. One is large like 3/8" OD and it's getting the T'd off PCV valve hose. The other is getting the va*** advance small diameter hose from the dizzy, and the other small one is capped. I connected a small diameter hose to the small tip on the forward pasenger side of the carb and it does not have enough to power the wipers. Anyone have the correct Va***m diagram for the 8BA? I also read on here of Va***m fittings on the 4bl manifold.. I don't know where those are? I may be blind. Maybe it's all the fumes!!. They're all shooting out of the cap top on the top of the filler tube. Can I install a br*** tip halfway up the tube and feed it back into the air cleaner? Ozzie
I am not familiar with the flatheads, but vacuum wipers use manifold vacuum to operate and a dual action fuel pump to help pull vacuum when there is low engine vacuum. If just using manifold vacuum, they will not operate at low vacuum as in pulling a grade. Manifold vacuum for the wipers (and all other vacuum accessories) should have a dedicated vacuum source (tap just a single runner) (to prevent possible flow reversion) whereas PCV vacuum source should be at the intake carb plenum to distribute the fumes evenly a**** all runners. You can get an accessory vacuum pump to help operate the wipers.
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