The Stovebolt Site Forums The Shop Area Paint and Body Shop Wiper Conversion

I ordered and installed a 12v wiper conversion from Classic Parts (https://classicparts.com/chevy-gmc/...ersion-12-volt#product.detail.attributes) back in 2022 and now that I am finally getting to the point of trying to get the wipers functional I can not find the instructions that were apparently with the kit.

As installed the wipers actuate but do not sweep very far (maybe a 30 degree arc) and depending on where the wiper arms are mounted try to initially rotate opposite of what I expected from the parked position.

I thought maybe I had the arm pivots that mount to the cowl inverted but there does not appear to be enough room between the cowl and the defrost duct for the pivot to be inverted (actuator arm above vs. below the pivot center).

Any insight regarding how to proceed would be appreciated.

Sounds like you need to install all the parts once the motor has been powered up and parked. If they go the wrong direction when starting, it wasn't in park.

Its fairly easy to find this Roger...Before you begin
Disconnect the battery: Ensure the battery is disconnected to prevent electrical shock and short circuits.
Gather tools: You will need basic hand tools like a wrench and socket set.
Obtain the kit: You will need a 12-volt electric wiper motor conversion kit for your specific vehicle, which includes the motor, wiring, and switch.
Test the system: Before full installation, test the system with a fully charged 12-volt battery to ensure it works correctly.
Installation steps
Remove old components: Disconnect the wiring, remove the old vacuum motor, and disconnect any associated linkages. Some kits may require you to remove the cowl panel to access the motor and its mounting points.
Mount the new motor:
Install the new electric motor in the stock location. Some kits may require minor modification, like grinding to fit the mounting bracket.
Secure the motor with screws, potentially using rubber mounts as provided with your kit.
Adjust the motor's position to ensure the linkage rod aligns with the stock wiper transmission.
Wire the new components:
Connect the wiring harness to the motor.
Connect the red wire to a fused, 5-amp power source.
Ground the intermittent switch to the chassis. The motor itself grounds to the body through its mounting.
Install the switch:
Mount the new switch in the original switch location. This may require some adaptation for the stock knob.
Ensure the switch is oriented correctly for the knob to function properly.
Final assembly and testing:
Reconnect the linkage and check for smooth operation.
Reinstall the cowl panel if it was removed.
Connect the battery and test the new 12-volt system with the new wiper arms and blades before fully reassembling.

Guitplayer - my truck did not have anything in place when I got it, the kit I received was installed about 2 years ago, long before I had everything else installed in the dash or windshields in place. Because the system was all new (wiper motor, linkage, wiper arm pivots, etc. and the kit came with the switch it seemed straight forward at the time. Now that I have glass and wiper arms I am finding that I need to probably change some of the assembly but it not nearly as accessable now with all the instrumentation, heater, defrost ducts, etc. in the way. I was hoping to be able to find an instruction sheet but so far no luck. I probably will contact Classic Parts to see if they can email me a copy.

thats for your motor. 1947-53 vehicle's wiper motor to 12-volt electric instructions.
IDT they'll have instructions for not having anything in place.

I installed a New Port motor on my 50 3100 and could not get it the work right even with the instructions. I called them and they suggested that the motor's control arm was not clocked right when it was assembled by them. They were right. I had a lot of monkeying around to do with that control arm before I had everything adjusted correctly.
If I were you, I would follow Guitplayer's instructions before you monkey with clocking the control arm on the motor.

Thank you 52Carl, the wiper project is on hold for the moment but will be tackled over the winter.

I took another look at the wiper linkage and it appears I may have had the two arms connected to the wrong pins on the actuator. The passenger side is easier to see and when the motor was activated the arm would travel part way before binding up. However, when I reversed the linkage connections I discovered that the motor to actuator spline connection must be stripped as the actuator only moves a small amount while I beleive the motor continues to rotate. I will need to remove the motor to get a clear picture of the problem and develop a solution.

For future reference can someone confirm with the acuator pins basically vertical (parked) does the link to the passenger side wiper connect to the upper or lower pin?

The extent of the wiper project just got a lot bigger so definitely something I will takle over the winter. There are a few other things I would like to get done before winter sets in but it is getting late in the season with predictions of our first snow coming this weekend.

If I'm looking at this film strip picture correctly (attached below), on the original vacuum motor the passenger side arm attaches to the upper pin and drivers side to the lower pin. I believe it's a view from the inside of the cab facing forward.

I believe you are correct, Dan. Upper pin to the passenger side and lower to the drivers. If the passenger side rod was connected to the lower pin, I believe it would interfere with the pivot linkage for the cowl vent.

Thank you both for the additional information. I originally had the passenger side connected to the bottom pin and while it cleared the cowl vent it wasn't by much. The problem was that with the links connected as I had them the links tried to push the pivot the wrong direction causing it to bind in the cowl which I did not realize until it was too late.

The wiper arm attachment to the motor shaft was not splined but two set screws so I was able to related the arm on the shaft without needing to replace any parts.

I got the wiper arms installed and was able to verify that they swipe without bottoming out either the under dash links or the wiper arms.

One step from the service manual that was helpful was to stop the wipers with the actuator arm (on the electric motor in my case) vertical and then install the wiper arms in the vertical position. That basically puts everything at a mid point in their respective travels.

The overall sweep of the wipers is not great, about 45 degrees so I am glad I am not planning on driving in the rain much if at all. I will probably add Rainex as an additional protection measure.