JackConnick
Senior Member
- Joined
- Aug 19, 2022
- Messages
- 288
- Location
- Seattle, WA
- Vessel Name
- Paradox
- Vessel Make
- 1991 Grand Banks 36 Classic
Notes on replacing repairing windshield wiper assemblies on Grand Banks 36 Classic.
This has been a way more complicated repair as there are so many variables and poor support available. I spent a frustrating time figuring this all out and decided to post this in hope of helping others. There wasn't a lot of info on various forums.
On my boat the motors are in “Unitized Assemblies” of the motor with a drive arm, linkage and pivot arm in a u-shaped carrier. Other newer boats may have something different in a sealed modular unit. Photos below are of the old unit.
Basically the motors all rotate 360°, and push-pull the linkage to the pivot arm to make the arm go back and forth.
Arm park is controlled by the position of the drive arm, when the motor is in park position. Blade Sweep (width) is controlled by the length of the pivot arm (there are 3 positions), as well as position of the drive arm on the motor shaft to a degree. To increase the sweep you shorten the linkage position on the pivot arm. Arm length can enter into it, but I just kept the same 20” arms.
Removing the assemblies wasn’t hard after I removed the outside parts. There’s just two screws on either side. The blade arm lifts straight up to release the spring, then pull off. But they usually are all corroded up, I just cut them off the pivot arm with a dremil.
Commonly, the pivot arm gets corroded and freezes up, or the motor burns out. The wiper switch will then click and shut off. Troubleshoot and test each part to see what’s going on.
Pivot Arm: The pivot arm bolts from the outside and the blade arm snaps on to it and in turn is bolted. The pivot arm is ordered by its length. On my boat it’s a 3” shaft.
www.amequipment.com
Switch: Cole Hersee 75221-09 | Fisheries Supply. Note position of old wires, as it can be confusing.
Motors: The motors on these say “United Technologies” who are long out of business, but they were made by Bosch. Trying to find that exact/updated p/n motor proved fruitless and the manufacturers weren’t much help. However something very similar is fairly easy to find.
On my boat I needed a 12V, 2 speed, coast to park, right hand drive. This is a 3 wire unit, plus ground. Many come with a fifth wire for switch, not used.
It fits most older assemblies such as United Technologies. AM also has one, but it’s more expensive, and they weren’t helpful that it would fit. You can find 24v or left hand drive units as well.
The plug or the motor will be labeled with a “L” low, “H” high, “P” park, “X” ground. Ignore the “S” for switch. Note which is what before you remove from the old motor, or test with a VM. Wires were numbered on my GB.
All hardware for the Wexco motor has to be bought separately. M6 mounting bolts and a M8 flange nut for the shaft.
The drive arm on the old Bosch motor was oblong. I used was this for the Wexco motor.
However to get it on the tapered shaft I had to taper the hole on it with a series of drills.
Other Parts:
Pantograph adapter: Pantograph Adapter for 230 Series DC Gear Motors - 305-1007, 44.45 mm (1.75")
Arms: Standard Duty Pantograph Wiper Arm, Dry, Tapered Knurl Interface, 1.75" Bridge Width - 352-0057, 510 mm (20") Arm Length: 352-0057, 510 mm (20")
Blades: Standard Duty Wiper Blades - 302-1200, 510 mm (20") - These work much better than the flat blades that were on the old units.
Method:
Replace the assembly parts as necessary and remount the unit. I would replace all of the external parts. Make sure the motor is in the park position. Then attach the pantograph arm and the blade to the arm. Slide the blade arm onto the shaft and push hard to snap it up vertically, then rotate so the blade lands in the park position, then push down on the end onto the tapered pivot shaft holder, then snap it down to the glass at the side. This takes some practice, but this is how you adjust where it sweeps. Tighten the cap nut down but not too hard, so you can readjust the arm as necessary. Test sweep and adjust. If you have too short a sweep, remove everything and move the linkage on the pivot arm in to shorten, or out if it’s too wide. It may be necessary to change the position of the drive arm on the shaft of the motor, but I just placed it where the old one was.
Where to Buy:
I bought most parts at AM Equipment in OR. They are a manufacturer.
www.amequipment.com
Support was variable depending on who you got on the phone. Some sales persons will have you fill out a form to give to their engineers, taking days to tell you what you already know if you’re doing a replacement.
Lisa was maybe the best person, but then flaked out when I need a motor, saying they don’t have anything like a Bosch, which was incorrect. There support docs were pretty poor and somewhat out of date.
Wexco is another manufacturer and has similar parts. Their retail arm is Autotex. Autotex sells on Amazon, Zoro and other places - shop around with your part numbers. I called for some info and did get a return email, but further questions went unanswered.
Their support docs are pretty good.
www.wexcoind.com
Zoro.com has a very good selection of parts at great prices (better than Amazon) with free shipping and good sales support (no tech support). They have lots of 20% off website codes.
This has been a way more complicated repair as there are so many variables and poor support available. I spent a frustrating time figuring this all out and decided to post this in hope of helping others. There wasn't a lot of info on various forums.
On my boat the motors are in “Unitized Assemblies” of the motor with a drive arm, linkage and pivot arm in a u-shaped carrier. Other newer boats may have something different in a sealed modular unit. Photos below are of the old unit.
Basically the motors all rotate 360°, and push-pull the linkage to the pivot arm to make the arm go back and forth.
Arm park is controlled by the position of the drive arm, when the motor is in park position. Blade Sweep (width) is controlled by the length of the pivot arm (there are 3 positions), as well as position of the drive arm on the motor shaft to a degree. To increase the sweep you shorten the linkage position on the pivot arm. Arm length can enter into it, but I just kept the same 20” arms.
Removing the assemblies wasn’t hard after I removed the outside parts. There’s just two screws on either side. The blade arm lifts straight up to release the spring, then pull off. But they usually are all corroded up, I just cut them off the pivot arm with a dremil.
Commonly, the pivot arm gets corroded and freezes up, or the motor burns out. The wiper switch will then click and shut off. Troubleshoot and test each part to see what’s going on.
Pivot Arm: The pivot arm bolts from the outside and the blade arm snaps on to it and in turn is bolted. The pivot arm is ordered by its length. On my boat it’s a 3” shaft.
Pivot Shaft Assembly - AM Equipment
Product Details: Assembly includes: Shaft Black cap nut Lockwasher Tapered knurl Rubber cap Nut Metal washer Rubber washer Pin (adjustable to A, B, or C position to achieve desired sweep angle) Locknut
www.amequipment.com
Switch: Cole Hersee 75221-09 | Fisheries Supply. Note position of old wires, as it can be confusing.
Motors: The motors on these say “United Technologies” who are long out of business, but they were made by Bosch. Trying to find that exact/updated p/n motor proved fruitless and the manufacturers weren’t much help. However something very similar is fairly easy to find.
On my boat I needed a 12V, 2 speed, coast to park, right hand drive. This is a 3 wire unit, plus ground. Many come with a fifth wire for switch, not used.
It fits most older assemblies such as United Technologies. AM also has one, but it’s more expensive, and they weren’t helpful that it would fit. You can find 24v or left hand drive units as well.
The plug or the motor will be labeled with a “L” low, “H” high, “P” park, “X” ground. Ignore the “S” for switch. Note which is what before you remove from the old motor, or test with a VM. Wires were numbered on my GB.
All hardware for the Wexco motor has to be bought separately. M6 mounting bolts and a M8 flange nut for the shaft.
The drive arm on the old Bosch motor was oblong. I used was this for the Wexco motor.
However to get it on the tapered shaft I had to taper the hole on it with a series of drills.
Other Parts:
Pantograph adapter: Pantograph Adapter for 230 Series DC Gear Motors - 305-1007, 44.45 mm (1.75")
Arms: Standard Duty Pantograph Wiper Arm, Dry, Tapered Knurl Interface, 1.75" Bridge Width - 352-0057, 510 mm (20") Arm Length: 352-0057, 510 mm (20")
Blades: Standard Duty Wiper Blades - 302-1200, 510 mm (20") - These work much better than the flat blades that were on the old units.
Method:
Replace the assembly parts as necessary and remount the unit. I would replace all of the external parts. Make sure the motor is in the park position. Then attach the pantograph arm and the blade to the arm. Slide the blade arm onto the shaft and push hard to snap it up vertically, then rotate so the blade lands in the park position, then push down on the end onto the tapered pivot shaft holder, then snap it down to the glass at the side. This takes some practice, but this is how you adjust where it sweeps. Tighten the cap nut down but not too hard, so you can readjust the arm as necessary. Test sweep and adjust. If you have too short a sweep, remove everything and move the linkage on the pivot arm in to shorten, or out if it’s too wide. It may be necessary to change the position of the drive arm on the shaft of the motor, but I just placed it where the old one was.
Where to Buy:
I bought most parts at AM Equipment in OR. They are a manufacturer.
Standard Duty Wiper Systems Archives - AM Equipment
www.amequipment.com
Lisa was maybe the best person, but then flaked out when I need a motor, saying they don’t have anything like a Bosch, which was incorrect. There support docs were pretty poor and somewhat out of date.
Wexco is another manufacturer and has similar parts. Their retail arm is Autotex. Autotex sells on Amazon, Zoro and other places - shop around with your part numbers. I called for some info and did get a return email, but further questions went unanswered.
Their support docs are pretty good.
Windshield Wiper Technical Resources | Wexco Industries
Zoro.com has a very good selection of parts at great prices (better than Amazon) with free shipping and good sales support (no tech support). They have lots of 20% off website codes.
