Wiper Replacement

Among my many trawler knowledge challenges I have a particularly acute one in the area of windshield wipers.

Grand Banks 42', one wiper arm fell off the threaded shaft and another came loose where the blade unit attaches to the arm. Motors work fine although shafts could be cleaned up to remove rust. Pics, including one of the center wiper motor (all 3 are the same), are below. Looking at all three they are old and tired. I have no idea what brand/make or type they are. I would like to replace them but haven't a clue where to start. Special order $$$ from Grand Banks or available at any good marine or automotive supplier? Can someone point me in the right direction? What are the important pieces of this to look for in a replacement? Wiper length, how they attach to the motor shaft? Looks like 1/2" shaft or so which is threaded. Current blade unit seem to just push on to the shaft and are hold on by a metal clip that springs into the threads?

Any comments or help appreciated.

I’d start with Defender. When we replaced one of ours, I started there. They list several different manufacturers and then you go thier individual web site. Hold on to your wallet though.

https://www.defender.com/category.jsp?path=-1|7504&id=2290232

Search the 'net. I found a 'Wipers.com-ish' place that has everything. Sorry, I lost the site. And they now email me about every week which goes to spam and is gone. I'll try to get you the site after the next spam.

greetings,
Mr. f. Best #'s I could make out from the picture blown up is AFI 34000. Just one of many hits on google...AFI 34000 MRV 2-speed Wiper Motor

Last year I found this company on the internet. They are a school bus parts replacements company with a good selection of wiper arms and blades. I have had some of their arms on our boat for a year now and are working great. Much cheaper than the marine stores and the same parts.
http://https://www.tacbusparts.com/

The link doesn't seem to work so try entering it manually.

I just got another spam from 'em. It's WiperParts.com

We found some new wiper motors at the IMTRA booth at the Seattle Boat Show a few years ago and subsequently discovered they have a very good selection of wipers/motors online.

Marine Wipers - Marine Systems - Imtra Marine Products

Thanks for the hints and links. Again, my motors are fine. Is the 1/2" threaded shaft a normal setup? Are they ALL sort of the same type of attachment? Can't really see how to unattach them from the shaft but didn't look real close. I would think that there is some way to push on the metal "spring" that allows the unit to come off.

In my experience, if the knurled driver is meant to be replaceable, there will be a set screw drilled into the side of it, or there will be a nut holding it and the wiper arm to the wiper shaft. Perhaps you did not see it from the angle you were looking from? If there is no set screw, than the part is not replaceable and is actually part of the wiper shaft. I don't see a nut holding your wiper arm on in your pictures.

firstbase said:

Thanks for the hints and links. Again, my motors are fine. Is the 1/2" threaded shaft a normal setup? Are they ALL sort of the same type of attachment? Can't really see how to unattach them from the shaft but didn't look real close. I would think that there is some way to push on the metal "spring" that allows the unit to come off.

Click to expand...

I had to buy a new motor, when the smoke escaped. It came with the threaded shaft as part of the replacement.

I'm dealing with the identical issue; one of my blade/arms is poor and the other is awful. Look just like yours. (BTW, I think you have a splined shaft, not a threaded one) ...if it is the same, there should be a little set-screw, which probably wasn't very effective when you yanked the arm off.

I've never been able to set my blades to just sweep the windshield. They always cross one side of the frame or the other. I'm thinking one of the pantograph types may be the solution. Does anyone have experience with these.

Check the condition of the stub the arm goes onto. It was hard to tell from the pic. If it is degraded you`ll have trouble getting a solid grip for the arm.

Russell Clifton said:

In my experience, if the knurled driver is meant to be replaceable, there will be a set screw drilled into the side of it, or there will be a nut holding it and the wiper arm to the wiper shaft. Perhaps you did not see it from the angle you were looking from? If there is no set screw, than the part is not replaceable and is actually part of the wiper shaft. I don't see a nut holding your wiper arm on in your pictures.

Click to expand...

Here is an enlargement of the shaft pic. Looks like there is a hole at the end that may be a set screw. Will check it out tomorrow. Now that I have my bearings on this a little I find I was making this a bigger issue than it really is. I thought these would be 30 year old Grand Banks parts, not made, etc. Thanks FF for pointing out the numbers on the wiper motor which I hadn't noticed yet. Search for the model shows it for sale on Amazon and an everyday brand with many matching arms and blades. Shouldn't be too hard to deal with. The geared end of the shaft on the one that came off seems to be in very rough shape. Can't see much of the gearing left at all. May end up replacing the whole motor if there is no way to replace just the knurled end. Appreciate everyone's comments and Mr. FF's sharp eye!

BruceK said:

Check the condition of the stub the arm goes onto. It was hard to tell from the pic. If it is degraded you`ll have trouble getting a solid grip for the arm.

Click to expand...

Yep, here is an even bigger enlargement. I would think that if you could look up wiper shaft degradation it would show this picture....looks like it has been spinning back and forth for quite a while.

AlaskaProf said:

I'm dealing with the identical issue; one of my blade/arms is poor and the other is awful. Look just like yours. (BTW, I think you have a splined shaft, not a threaded one) ...if it is the same, there should be a little set-screw, which probably wasn't very effective when you yanked the arm off.

I've never been able to set my blades to just sweep the windshield. They always cross one side of the frame or the other. I'm thinking one of the pantograph types may be the solution. Does anyone have experience with these.

Click to expand...

Agree. Just wasn't looking closely. The threaded part of the shaft is just for the nut to tighten against the superstructure. The arm itself sits on the splined end as shown above and the spring catch sits inside the groove.

Greetings,
Mr. f. Um, RTF not to be confused with Mr. FF.

Yup. That's a tapped hole for a set screw I betcha BUT it may be a real bear to remove.
What I would do to potentially make my life a LOT easier is remove the motor mechanism entirely. Once sitting on "the bench" (probably the galley counter with a couple of sheets of newspaper underneath) you can soak the heck out of the end with PB blaster or your favorite penetrant before attempting to remove, what I suspect will be, the very stuck set screw. You may even try gently heating the knurled end with a small torch to help things along.
BEFORE you try to unscrew the nut from the threaded shaft (the 1/2" piece), clean the threads up as best you can with a small wire brush and some of the aforementioned penetrant of choice. Go very gently with the wrench.
Cover the area around the shaft with masking tape to prevent scratches.

Edit: I think once you get the splined piece off it should clean up quite nicely with a wire wheel. Run a tap through the threads, get a new SS set screw, and you're off.

An cheaper alternative to a new unit might be to have a local machine shop take the end off. Too bad I wasn't closer...

AFI is Marinco. I bought a Marinco motor years ago from the Surplus Center. Their stock rotates and right now it looks like they just have 24V model motors. But when they stock what you need, their prices can't be beat.

Surplus Center

AFI replacement blades should be easy to find online. I think the last arm and blade I bought ran about $25. I believe I had to pull the blade to its upright position (off the glass) to release from the shaft.

I don't believe the shaft is removable, but at $30 for a new motor (if in stock), it's a relatively cheap fix.

Bigger picture helps,the grooves on the stub may not be enough to lock the rotating arm part which slides over them. But temporarily, epoxy may be your friend, combined with the screw fixing, while you find a new motor and stub. When the epoxy fails,do the replacement.

RT Firefly said:

Greetings,
Mr. f. Um, RTF not to be confused with Mr. FF.

Click to expand...

What was I thinking?!?! Actually, I was thinking FireFly and typing too fast. My bad as they say. Thanks for the comments. Again, relieved to find that this isn't a big deal and appreciate the directions.

FlyWright said:

I believe I had to pull the blade to its upright position (off the glass) to release from the shaft.

I don't believe the shaft is removable, but at $30 for a new motor (if in stock), it's a relatively cheap fix.

Click to expand...

Thanks for the link and the hint. That's how it comes off. Couldn't figure that out. Opening relieves the spring pressure. Duh. Glad I'm not in this alone...!!!

BruceK said:

Bigger picture helps,the grooves on the stub may not be enough to lock the rotating arm part which slides over them. But temporarily, epoxy may be your friend, combined with the screw fixing, while you find a new motor and stub. When the epoxy fails,do the replacement.

Click to expand...

Good temp solution. I think the grooves are toast but will see today.

Greetings,
Mr. f. IF it is possible to purchase a new wiper arm with a set screw fastener rather than the spring clip (never liked those spring clip do-dads. Quite difficult to align for best "sweep") you may still be able to use the existing splined knob after cleaning it up.
Keep in mind you will have to ensure the bore of the new arm socket will fit what you have.

three of those on my boat. The one in the centre is on a wider window than the other two, so the sweep is larger. The tips of the blades have each dug a small recess is the teak surround. This must have occurred long ago, as the varnish in those recesses hasn't been damaged since I have owned this boat.
All of which is to observe that there must be an adjustment of the sweep, only visible if you open up the motor housing. The positioning of the blade on the post will control keeping the blade away from the window frames.

Keith, I think you'll find that the motor/transmission unit is marked and sold with a fixed sweep. Were you to open one up, you'll find that the motor turns a worm gear which in turn causes a disc to rotate. That disc has a pin whose distance from its center sets the sweep. (Lousy description betrays a hazy memory for the details.)

Greetings,
Mr. k. Mr. DH is correct. The sweep is non adjustable via the motor mechanism BUT is adjustable by means of arm/blade length. The longer the overall length of the arm AND the blade, the greater the arc that the bottom of the blade traverses. So, if the bottom of the blade contacts the window frame, either install a shorter arm or move the bottom tip of the blade closer to the motor.

koliver said:

three of those on my boat. The one in the centre is on a wider window than the other two, so the sweep is larger. The tips of the blades have each dug a small recess is the teak surround. This must have occurred long ago, as the varnish in those recesses hasn't been damaged since I have owned this boat.
All of which is to observe that there must be an adjustment of the sweep, only visible if you open up the motor housing. The positioning of the blade on the post will control keeping the blade away from the window frames.

Click to expand...

The Marinco motor I bought had multiple settings for angle of sweep....something like 80, 110 degrees and maybe another.

Greetings,
Mr. FW. I stand corrected.

AlaskaProf said:

I've never been able to set my blades to just sweep the windshield. They always cross one side of the frame or the other. I'm thinking one of the pantograph types may be the solution. Does anyone have experience with these.

Click to expand...

Love my pantograph wipers! They easily cover more of each windshield than the simple ones, and are more adjustable. Have AFI's on my 26-footer and now AME on the Nordic Tug.

The motor I found that matches model number exactly only mentions an 80 degree sweep. I did find other similar models that do have user variable sweep.

Pantographs would be great but do they fit on the same motor/shaft I have or do the motors have to be flipped out to something that matches them specifically? Not sure how they attach.

Remember, before I started this project my involvement with windshield wipers was to tell Goodyear "No, I don't want them replaced" as they tend to lie 50% of the time. Due to that I tell them yes every other time.

RT Firefly said:

Greetings,
Mr. f. IF it is possible to purchase a new wiper arm with a set screw fastener rather than the spring clip (never liked those spring clip do-dads. Quite difficult to align for best "sweep") you may still be able to use the existing splined knob after cleaning it up.
Keep in mind you will have to ensure the bore of the new arm socket will fit what you have.

Click to expand...

Good idea Mr. RTF. Going to the boat today to investigate further. My wife offered her suggestion after seeing several of the prices I was looking at..."Why don't we get some RainX and try to not go out in the rain?".

Actually I found the prices of most of the motors/arms/blades much less than I expected. There are some that are up there though....