How I cleaned my wipers

[tundrawolf]

Hello,


When I got my first VW a few days ago, I noticed that the windshield wipers operated very slowly. It took 1.5-2 seconds to achieve one "wipe". Unfortunately this beetle has been stored by the ocean, and rust has set in all over the place.

So, I removed the windshield wiper assembly. It was difficult. The most difficult part was removing the passenger side vent duct from inside the trunk. I pried hard enough to break it, but it came loose and did not break. Your mileage may vary. Removing the center duct was also difficult.

One thing I learned, is to make a dink (punch) mark on the output shaft of the gear assembly and the drive crank. If you don't, though, it's no big deal. The Haynes manual tells you to temporarily connect the gear assembly, let it turn one revolution and stop on its own. Then, align the drive crank 15 degrees from the axis of the assembly long-ways, facing to the right. (Axis including motor, sorry, the picture is a better description).

So anyway, I found that there was quite a bit of rust and corrosion on the driver's side. It took a significant amount of force to remove the wiper shaft out of the bushing.

I used a very fine "grinding" attachment (More like polishing) to clean up each shaft to a chrome finish. The drivers side shaft had tons of corrosion and pitting in one area. I also cleaned up every metal wearing surface, and both wearing surfaces of the motor itself. I used a wire brush in the dremel to clean up the bushings throughout the assembly. I am sorry I didn't take pictures, I only have my camera phone and transferring pictures is a PITA. (I have found a better way today, though)

Anyway, it turns out that the brush holder plate is only held in by 3 rubber mounting nipples. While two of the nipples were in remarkably good condition, the third crumbled into dust. I went and purchased a small (#10 if I remember right) fine thread bolt, nylon locknut, and two nylon washers.

I used the bolt head inside the assembly, and the threaded portion on the outside. The nylon washers are for two things: One washer directly under the head of the bolt to prevent electrical contact between the housing and the brush holder, and one washer between the brush holder assembly and the metal housing, as a spacer. I used a cutoff wheel and shaped a portion of the locknut to fit in the groove of the housing. I ground down one corner flat, and the flat side next to it I ground inwards a bit. It was a perfect fit.

Here are pictures of what I did:

(Sorry, right now my knees are my workbench!)

So, you are wondering how I got grease in the motor housing bushing. I don't blame you. That's a difficult one.

No mechanic should be without an ominous looking syringe! It's a flavor injecting syringe from Wal-Mart. I cut the end of the side-inject needle to make it a tip-inject needle. You cannot just suck grease up in through the needle, though. Using your fingers, with the plunger out, pack as much grease as you need into the barrel of the syringe. Then, insert the plunger and you are ready to inject grease in any nook or cranny you need to. There's actually a bit of grease in the syringe here, but it is almost the exact color and hue of the syringe body.

I thoroughly cleaned all grease from every surface and replaced it (After cleaning with the dremel) with 100% synthetic Mobile-1 grease. I adjusted the endplay of the armature to .010". The drive gear adjustment I just sort of did by feel. I thoroughly greased everything. I considered using Green Grease, however, it has terrible low temperature characteristics, and I may be using the wipers in snow, so I stuck to the Mobile-1.

I also cleaned up the commutator, which was in remarkably good condition, actually with the light Dremel abrasive polishing wheel. The brushes had lots of meat left on them.

I had the opportunity to use the wipers last night during a little off-roading, and they worked flawlessly. The low speed is 15 times faster than when I originally turned it on. It wasn't hard to do, either. The picture in the Bently manual (Fig. 10-2) is enough to actually assemble the arms. But it's easier to write it out when you take it apart.

[slomazzo73]

How much grease should I pack into the drive housing? Should the teeth of the drive gear be full of grease? Also, should the top of the drive gear that the three metal brushes rest on be full of grease?
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1973 (Vin: 113-xxx, Model 113 841) Deluxe (non super) Beetle. Born Wed., Aug. 23rd, 1972. Flat windshield, upright spare, generator and oil bath. 95% Original.

[tundrawolf]

You will no doubt get many opinions on how much grease to put in anything. I am of the "Don't be shy with the grease" crowd. I would rather have too much than too little. That being said, there is always a good thing to having enough grease in excess to become loose, soft, or expanded in the event the mechanism heats up, and thus slowly re entering the mechanism as it heats up.

As far as the brush housing goes, you don't want *any* grease where it can contact the brushes. If enough grease fills the grooves of the commutator, you can electrically bridge each coil and cut the output of the motor by a lot.

The reason for the syringe is to get grease into the bushing in the back of the housing where the motor shaft goes into. It's a guessing game if you use anything other than a syringe to get it into the bushing cavity.

Remember to set the endplay as per your manual.

[slomazzo73]

Thanks, can you read my post: Thrust cone (aka wiper armature nipple)
and let me know what you think.
_________________
1973 (Vin: 113-xxx, Model 113 841) Deluxe (non super) Beetle. Born Wed., Aug. 23rd, 1972. Flat windshield, upright spare, generator and oil bath. 95% Original.

[tundrawolf]

I thought I answered it, can you get me a picture of it?

[slomazzo73]

There is a little plastic nipple called the, "thrust cone" that fits at the end of the armature of the windshield wiper motor as shown in the illustration. It is in place on my unit and working fine, however, the diagram does not show another "thrust cone" at the other end of the armature. This would be at the drive crank end of the armature. Mine has one, or rather it was there and dislodged and mixed in with the grease and I think this is what was causing a grating noise as my motor was running. So as I said, the illustration does not show this extra nipple. Is it supposed to be there? I would think that I could not adjust the armature end play properly if this piece was in the way or not there at all....any ideas?

_________________
1973 (Vin: 113-xxx, Model 113 841) Deluxe (non super) Beetle. Born Wed., Aug. 23rd, 1972. Flat windshield, upright spare, generator and oil bath. 95% Original.

[tundrawolf]

OK you are bringing back some memories. There is no thrust cone on the driveshaft end of the armature. That load is supported by the bushing inside the housing. Definitely grease the thrust cone well, and make sure there is enough grease in the cap where the thrust cone goes into, I like enough so that some squeezes out when the motor is reassembled.

You do not have to set the endplay of the armature, only the drive gear (25) which is set by the adjustment screw (22) and then set by the locknut (21).

The thrust cone takes care of any "play" that could be in the armature, not that it is of extreme importance, because it is worm gear drive and capable of operating with an amount of play.

How does your thrust cone look? How do the teeth look on the drive gear (25) and the worm end of the armature? How much slop or play are in each of the bushings inside the unit?

[GA_Boy]

Nice post. I don't know the cost of your syringe but I buy Cattle needles from my local "Feed and Seed" verry cheap. I keep one filled with white grease on my workbench. They have several sizes.
Marvin

[BWD]

How the heck did you get the brushes back in? If I had any hair, I'd of pulled it all out by now!
_________________
BWD
JHC
member #2850
1966 Beetle
_____________________________

[tundrawolf]

[BWD]

[aircooledbus]

Just get some small twine, or yarn, install your springs and slide your brushes back into the boxes, hold them in place and have a friend tie a loop and knot them on the back side. Now make sure they are tight enough and then slide the commutator past them and into place. Cut string on one side of knot and pull the string out. You coud also use small rubber bands to hold them in place, but I didn't have any that small. Note: make sure you have the string located under the brush pigtails before you start.

[tundrawolf]

Yes I understand that, however not with the commutator near the brushes. I need a pic of the assembly to engineer a solution. By all means try the yarn solution.

[Johnny Martin]

Good post man thanx!!
_________________
1971 SUPER BEETLE
AE489501 carb Solex 30 pict-2 with dist 0 231 137 021
113 905 205 M

[jays]

i put the brushes back in by opening the back part of the housing putting the brushes on first. and as im assembling everything right when its about the close i put the springs in while holding them down with a skinny screwdriver i'd close the back door open by pressing it in little by little with a bigger screw driver.



also i was afraid to put to much grease int he gear housing becaus ei didnt want to mess with the contacts behind #19 and the metal plate on #25? does it matter if i want to fill the whole housing with grease?
_________________
1970 Käfer

[jays]

[tundrawolf]

I have noticed grease on the contacts of the commutator and it didn't affect the motor. The problem with getting grease on the copper contacts doesn't so much have to do with conductivity, as it does with getting between the contacts and attracting the carbon dust that the brushes leave. The dust can collect and over time cause resistance variations between the contacts, reducing the efficiency of the motor and increasing heat and current draw.

So you don't want to go nuts. But I have seen people use just a tiny dab of grease and it really bothers me-why go through all that trouble of disassembling the motor properly, only to put in enough grease for 3 years worth of service, if that?

[Chris Vellat]

I just did this using a pipe cleaner and a straw...Big green straw from Starbucks is the perfect diameter for blowing grease into the bearing, and three sections of pipe cleaner ~1-3/4" long perfect for holding the brushes back - wrapped around the braided wire.

I even went so far as to remove the magnets, I wriggled the studs out from the outside using a pair of pliers, and re-installed them using an aluminum yard stick (non ferrous) and an 8mm box end wrench.
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(3) '69's
'67 Baja
'74 Super
'73 Bay
(2) '77's

[tundrawolf]

Right on...