VACUUM WIPER MOTOR M151 in M38, (Some questions)

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JAM
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VACUUM WIPER MOTOR M151 in M38, (Some questions)

Post by JAM »

I have two vacuum wiper motor used in CJ3A, which completely disarmed to make them work even fabricated a new rubber seal on the piston, with a good result.
Later I bought the wiper arms of M38, which have a ribbed cone and I encountered the following problem:
The ends of the shafts of the motors are in poor condition,

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therefore the striated cone does not fit well in the tapered shaft. Obviously missing the nut that secures it, but if I did, I note that the clamping area would be insufficient to transmit the torque and could loosen the arm and rotate the axle.
I say this because the small grooves that has internal cone, fail to connect to the shaft itself

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I decided to buy two new engines for M151 on ebay, after reading this forum, someone bought them, and except for some minor adjustment to fix the windshield was satisfied with his performance.

After finding out and seeing the figure of a vacuum motor M151 manual, I realized that at the end of the shaft is a ribbed cone which fits the arm, similar to the arms that I have.
But my surprise was that the engines are not aware striatum bought, but is a cylinder, and also the passage of the grooves is less than the cone that brings the arm.

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How is the procedure to release the fluted cylinder, and replace the knurled cone brought the arm? Is this possible?
Apparently it is put under pressure, as the looming cap is smooth, and could not be with a screw.

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I have not tried it out, without really knowing how is armed and do not break it.

This problem has been ?..., someone has been solved? M151 arms are different, and I have to buy again?
If they are different, how they hold on the striated cylinder?

I have some ideas for using the parts I have, but I would not pass me until I get some answers to my questions

Jose Angel
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swat
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M151 wiper motor and M38a1 arms

Post by swat »

Jose, take your wiper motor over to your bench vise and slip the shaft between the jaws, with the knob resting on top of jaws. Take a punch and hammer and lightly strike the center of the shaft. the knurled knob will come right off. I use M38a1 wiper arms on my M151 wiper motors (the jeep is a M38). If you are installing the motors on a M38 you will need a 3/4 inch stand-off between the wiper mount and the windshield frame. I don't know about adjusting for a M38A1 windshield. Be careful and don't let the motor fall on the floor when the knob releases from the shaft.
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Post by JAM »

Thanks swat, by tomorrow I'll try.

No I have a M38A1, but a CJ3A I am restoring it as M38.
I think the windshield (the part that concerns the wiper motor) is equal to the M38, so I have to take into account what I advise.
I noticed when comparing the two engines, the CJ3 against the M151. In the latter, the shaft is longer, therefore I must put some spacers on the inside.

The last question: after I put the ribbed cone on the shaft, how to hold the arm so as not to leave?
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Wiper arms for M151 vacuum motors

Post by swat »

After you have the knob pressed off, you will see that the shaft of the arm is ribbed just like the outside of the knob. The mounting hole in the M38A1 wiper arm is ribbed to accept a ribbed shaft. A M38A1 wiper arm will press right onto the shaft with just a light tap from a hammer. Your Cj3A windshield frame is basically the same as the M38. use a 3/4 spacer betweem the windshield and motor mount.
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Post by boelcke »

will a m38 wiper arm work? also with a 3/4 spacer do you need to shorten the rotating arm?
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JAM
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Post by JAM »

I pulled the cylinder and pressure was actually on the end of the shaft, also striated. (Not very mild considering the diameter)
Now I upgraded to a 5.8 mm diameter of the hollow cone that I'm putting striatum, since he has, is smaller than needed.

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Thinking about the procedure to put it is hitting, or in press, I am concerned that by supporting the engine vacuum could damage the rear which backs it, or the plunger is integral with the shaft.
I dropped the small back cover to see if I could directly support the opposite end of the shaft on something solid, and I see no risk of damaging the mechanism of oscillation.
I think I'll take the decision to place hot
But what surprised me is that by simply loosening two screws around the small cap, rubber stamp size has increased significantly, exceeding the cap, and has come all the way around 8O ... it's inexplicable. :o

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It may be that the rubber is degraded by the type of lubricant used in the process?
Now I have to make a new rubber stamp that it becomes impossible to place the same. :roll:

Believe it or not! :D
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