The Stovebolt Site Forums The Shop Area General Truck Talk windshield wiper motor....

How do I get the wiper motor to operate to always park the wipers on the down stroke?? I know there is a switch designed into the gearbox but how does it work?? I'm guessing there is some wiring that I am lacking.

Carl

you may have the transmission arms attached wrong, or you may have put the blade arms on when it wasn't in the park position - electric or vacuum? the electric park switch can only work one way if the unit was put together right ... you'll find a bit of info on it in the shop manual

Bill

ok...found my problem. In case anyone else runs into this issue, when wiring in the wiper motor the ground is the wire that has to be "switched". With the hot wire "switched" the part of the motor that actuates the small switch that parks the wipers does not work. I discovered the correct wiring by accident when I was checking/removing the ground wire and the motor suddenly parked. I wired the hot direct and "switched" the ground and they now the wipers park correctly.
Will always amaze me how that blasted electricity knows where it is going and how it wants to get there.

Carl

Joe - don't you have the original style motor with the cable actuating the switch on the motor? there's only one wire off that OEM unit, the mounting supplies the ground, the case mounted switch controls power

Bill

Did you check your vacuum lines? What can I say, those new-fangled trucks confuse me ....

cjoe, I am trying to find info on an odd set of wipers i got from a '58 big window. It has a motor with a worm drive and a crank arm on either side of the motor. It has a two speed electric switch and everyone told me they were aftermarket. They look really factory with clutch head screws and such. Does this sound like yours? :confused:

red58...I thought it was the original. But maybe not. There is no cable. Two wires from motor, small rectangular electrical box (relay?) mounted on it, maybe is for 2-sp operation or activates the park switch??? I wired the hot wire direct, ground is "switched". Turning off switch activates a small switch that reads the position of the gearbox and stops wipers at bottom of stroke.

59patchy....what you have sure sounds like mine. Wiper crank arms are mounted on opposite sides of the gearbox and the gearbox drives both sides at once (driver's side is on top and passenger's side is on bottom). It's funny but maybe not important but the wiper motor I installed in the '59 is the one I took out of my '58. I had to steal the crank arms too because the ones from the '59 would not fit the wiper motor from the '58. Anyone else have any info on this??? Is this motor a replacement or something that actually came on the '58s.

cjoe, this is exactly what I have. The only other reference I have found so far is a replacement switch for sale on ebay. It was NOS and came with the original AC/delco package tube. The seller said he was selling it as a part for a '58 because he had looked it up in a reverse parts application book. I think this may have been a special order or a GM factory retrofit. If anyone has more info, it would be appreciated. Thanks :p

I don't have a picture of the only style that was used on the TF trucks handy, but will get one tomorrow - sounds like you have an aftermarket unit, or one adapted from the 60's, when they started using electrical switches rather than mechanical, especially with having to change the arms ... got any pics of these units?

Bill

I dont have any pics Bill. Mine is installed now and putting pics online is one of those many things I havent had time to figure out yet. I would like to see pics of an original because I aquired 2 wiper motors with the '59 but because they are the slider actuated type I didnt think they were the correct ones for the truck. Maybe I am sitting on gold and dont know it.
How 'bout it 59Patchy, can you post some pics of our mystery unit??? Question, do you have the correct crank arms? The angle of the bends is different because of the positioning of the pins they mount on (opposite sides of the gearbox instead of both on the same side). You may be able to redesign arms to fit but the ones I changed out were quite a bit different. I didnt think to look but does your unit have any part numbers on it??

Carl

Carl, I can't post pics right now as my wife is out of town with the digital camera. I did go out to the garage and brought in my motor/arms/pivots and switch. The switch is a Delco Remy with two terminals and three detented positions. The motor is a Delco Appliance and has the stamped date of Jun 13 1959 on the side of the box you mentioned before. The motor base has a cast in number of D 4903628. Both arms have a 90 deg twist and are completely unlike the ones I have from my '59 vacuum setup. The box you mentioned appears to be a parking switch as it has a plunger coming out of the other side and a cam on one of the crank arms moves the plunger. I think I still have the original harness, but could you tell me how to hook it up just in case? I'll post pics when I can.

hey guys. I think you got some mystery info I've been looking for that's needed for a tech tip - the repro vendors always say there's 2 possibilities for the 58/9, one electric motor [the same as the 55-57] that works for 58/9 that originally had vacuum wipers, and another for 58/9 trucks that originally had electric wipers - the one for the 58/9 that I've seen [wrongly purchased by a friend with a 56] wouldn't work on any of the 3 58's I've seen, but 2 of them had vacuum

the trucks I've seen that had OEM electric were all the same, 56, 57 and 58, and the transmission arms were the same .... but it may be that my 58 was converted some time in the past using the earlier arms, even tho it appeared to be a very original, unmodified truck ... maybe it was a dealer conversion from vacuum using the earlier unit they had on hand

it appear's from what you 2 have, that by sometime in 58 GM had redesigned the electric wiper to the style they used in the 60's, and that used different transmission arms

so patchy, if you can get me the pics of your parts, I'd be obliged, and it'll help folks in the future ... I've already made note of the part numbers listed here

Bill

red58....looking at your wiper pics I'm guessing that one side of the gearbox is removed and it has 2 studs where the wiper transmission arms go (both on the same side)?? This unit is definately NOT what I have. I see the slider control and this is the same as the one I removed from the '59 as I dont need it with the motor I have. I have my wiper motor connected to a large toggle switch for now with the plan to use either a rotary or push/pull switch with an original chrome knob attached. Please post some pics of a complete unit if you can as I would like to compare 2 other motors I have.

59Patchy...my transmission arms also have a 90 degree bend/twist to them. Also the passenger side arm has a large offset to it compared to my other set of arms. I have a feeling the motor without the arms or visa-versa would give a man gray hair attempting to make things work. I am going to file these numbers you gave and if I ever have to remove mine again I will compare.

Hi Guys, I have a little more information on this set-up. The part numbers for wiper arms on this set are 381 (Right) and 382 (Left). I disassembled my switch (don't try this at home kids as is very tough on the switch) and found that it connects one terminal at a time to ground. With the three open terminals on the motor, I presume that one is power, and the other two go to the switch. Both the motor and switch must be grounded. This appears to be a two speed set-up. I will hook it up and try it if I get time. Hope this helps. :rolleyes:

ok , I've got pics of the "early" electric motor, front and back - this is the only style OEM wiper I've seen, and the repro from the vendors for 55-7 has the same configuration, but different motor and drive [made by Newport Engineering, excellent replacement] - the one said to be for 58/9 has a slightly different mounting arrangement, but the drive looks the same

I couldn't find the transmission arms right off, hafta dig deeper into boxes, but I'll get to that - the 5-7 arms do have a "kink" and there is a definite right and left, but I guess they changed some - will be interesting to see how

so if you're looking for originals to replace vacuum units, this is what you want .... and I'll be hoping for some pictures from Patchy of the other unit

Bill