When you say wiper arms do you mean the arms that are shown in my diagram numbers 17526 and 17527 or the other arms 17553?
If your wiper motor is having a hard time moving your blades the modern arms that you are using may be putting too much pressure on the blades. I had that same problem when I tried to upgrade to modern arms and "wrist action" blades like you have. Had to return to the original to get them to work well. You can get them at Mac's or C&G.
What I did was to install a small vac. pump to run the wipers. Have constant vac. regardless of engine vac.I'm not sure a photo would be as helpful as this diagram
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but if you'd like a photo I'll take some and post them.
The number on my '47 motor is SSM 114. I believe that is the Trico part number - the manufacturer of the motor. The Ford part number is 51A 17508-C
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but it has a different switch than is shown in the diagram for the 46.
I know a vacuum reservoir tank for the windshield wipers sounds like a good idea and Ford even manufactured and sold one as an optional accessory for the 46-48. I thought it sounded like such a great idea that I bought one and installed it. I have since taken it back out. Why? Here's the rub: A reservoir tank sounds like a good idea, the "theory" being that it would "store" vacuum so that when you accelerated or were cllimbing a hill and lost the constant continuous vacuum from the engine that the reservoir would take over and run the wipers until you let up on the gas and restored the manifold vacuum, right? Well, yes. That part worked pretty cool. When I mashed the gas, for whatever reason, I'd get about 7 full swipes of the wiper blades on the vacuum stored in the reservoir before it was gone and the wipers stopped - about 7 seconds. Then, I let up on the gas to "refill" the vacuum reservoir to get them going again. Right? Wrong! Here's why: It takes the same amount of time to "refill" the vacuum tank as it did to empty it - about 7 seconds - during which time there are not only no wipers but no power because the gas pedal has to be clear up to refill it!So, what good did that do? None! All it did was make the wiper operation "sloppy" and out of control. I decided I'd rather go back to having total control of the wipers by feathering the gas pedal just enough to keep them going if that's what I wanted or let then stop if I didn't need them constantly then, when I needed them, I could get them started immediately again by letting up on the gas pedal just for an instant for a quick swipe of the wipers then back to feathering or none until I needed a quick swipe again. I can see why Ford did not install the vacuum tanks as standard equipment. Owners would have soon bypassed them and gone with the strictly "manual" vacuum control.
The only way I can see a vacuum reservoir working is if it was hooked up to some huge vacuum port that would have to be made in the intake manifold at least as big as a power brake port so that the tank could be "refilled" immediately with a quick lift of the gas pedal while the tank could run the wipers for 7 seconds while the engine vacuum was gone. The Ford tank actually came with a larger hose to run from the carburetor vacuum port to the tank than the standard size hose from the tank to the wiper motor. But it wasn't big enough to really work.
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I installed a small vac. pump to operate the wipers. get constant wiper vac regardless of engine vac. Also aftermarket arms can be "tweeked" by stretching the arm spring or replacing it with a lighter one.
Actually I did install electric wipers. They were a pain in the a**. Parked in wrong position, noisy, jerky, never could get both wipers to stroke the same am't. Installed NOS wiper towers and linkage with the same results. The elect. unit was from a reputable early ford dealer and I talked to their tech at a show in Knoxville,Tn and he never heard of such a problem. Surprise! Ditched them, installed a NOS vac wiper motor, vac pump and they work like a champ. Used a vac pump from an import SUV.What does your vacuum pump run on? Electricity? If so, why not just install electric wipers?
Just curious.![]()
Actually I did install electric wipers. They were a pain in the a**. Parked in wrong position, noisy, jerky, never could get both wipers to stroke the same am't. Installed NOS wiper towers and linkage with the same results. The elect. unit was from a reputable early ford dealer and I talked to their tech at a show in Knoxville,Tn and he never heard of such a problem. Surprise! Ditched them, installed a NOS vac wiper motor, vac pump and they work like a champ. Used a vac pump from an import SUV.
I'm running 12V alt. I have seen vac pumps on E-bay, I believe, that are 6V.Still curious. Assuming that your vacuum pump runs on electricity, what does it come from? 6 volt or 12 volt? Generator or alternator? Sounds like an idea but don't think my 6 volt generator would keep up.
I agree with the "genuine experience of driving a vintage auto" but if I'm going to travel all over the U.S. I'm going the attempt to be as safe as I can and that includes operating wipers, turn signals, 3rd. brake light and power brakes. From the outside no one can tell these items are on my car. My wife and I were going from N.Y. to Fla. and I happened to think, We're probably the only ones traveling down this road, at 75 MPH, without power brakes. Guess what went on our car that winter.When I drove my '47 Ford in high school (45 years ago) and the vacuum wipers were so annoying I wondered why in the world Ford didn't put electric wipers in like modern cars had. It wasn't until I restored it a few years ago after it sat for 31 years and realized how feeble the generator was that I finally figured it out. There is just no way the genrator could keep up with electric wipers (or electric vacuum pump for that matter) if anything else like the headlights, radio, or heater fan was on. Just part of the genuine authentic experience of driving a vintage automobile. Wouldn't change a thing.![]()
I have posted many a problem in regards to my 47 Ford 4dr, and Old Henry has always come thru on information, help, diagrams and usually a spot on answer, he knows the 46-48's for sure.
You're right, but also no one else had power brakes. Do you think your 40's car will stop as fast as a new car with power brakes? That's my point and that's why we don't have 40's style brakes. It may not be period correct but when I'm driving down a 4 lane highway and am basically "competing" with new car that have ABS power brakes, halogen headlights, quick lighting LED tail lights, rack and pinion steering, I want all the help I can get.I'm thinking that there was at least one other person back in the 40's that went from New York to Florida just fine without power brakes. Maybe even more.![]()