Wiper Arm and Blades Notes
First published Mar 2017 (changes on-going) [Comments Added]


Removing Wiper Arm
Installing Wiper Arm

Drive Bushings are an Interference Fit!

Mechanical play in the Wipers

Reference Information


Removing Wiper Arm:  Wiper Arm is connected to Wiper Driveshaft, which comes through cowling under the Windshield, by way of a splined joint at the Drive Bushing of soft whitemetal.  At some point, it may become necessary to remove or replace the Wiper Arm.  This must be done carefully.

Inexpensive Wiper Arm Removal Tools are available, which hook under the lip of the attachment cup, to allow a simple one-handed removal of the arm.  These also prevent the cup from snapping away when released from the drive-post. 

If a removal tool is not available, below shows the alternate removal of Wiper Arm using a flatblade screwdriver as a lever...this will lever the Cup of the Arm off the Drive Bushing.  Proceed GENTLY!  Hook end of screwdriver blade under Wiper Arm Cup only and not Drive Bushing also...purpose is to pry Cup off Drive Bushing, not Drive Bushing from Driveshaft!!

Because of the big Tension Spring, which also serves to press the Wiper Blade onto the glass, Cup will tend to get pulled and rotate toward the Arm as it is pulled by the beefy spring, as shown here (3).  Mechanic should be aware and ready for this!! 

Wiper Arm Removal Options.  If a "Removal Tool" is not available, GENTLY(!) remove Wiper Arm with a lever, and lift the Wiper Arm off the splined Bushing.  The Retaining Spring (orange) is easily overcome to allow this .  Paintwork is protected and a strategically sized Fulcrum Block is used. 


Unfortunately also, if Bushing to Driveshaft connection has been weakened by any mechanical insults (such as not freeing the Wiper Arm from being frozen in-place in the winter) or anything of the sort which might make it weaker than Bushing to Arm connection, the Bushing might release from the Driveshaft...then it looks like the picture below!  That is why one must proceed gently with this and any other removal technique!  

Unsuccessful removal of Wiper Arm...Drive Bushing has separated from Drive shaft instead of Arm...at 3O'Clock Drive Bushing looks like it has endured some mechanical insult.  Drive Bushing needs replacement! 



From Facebook ("Volvo 122" Group) Posting...the white-metal Drive Bushing which is pressed onto the small (rusted) splined Wiper-Driveshaft, is missing in this picture.  The larger internally splined hole in the Wiper Arm base cannot be installed until this Bushing is present (and solidly connected to the driveshaft!).  Only with a solid connection between the driveshaft and Wiper Arm can high forces be transferred.  If not connected well, it wouldn't be the first time these high forces caused a Wiper Arm to become disconnected and lost on the side of the road...in a rainstorm...not so good! 


Wiper Arm Drive Bushing details, also showing two different style Retaining Springs on the Wiper Arm Cup...these don't do much in the way of keeping the Arm on Bushing...with the forces applied to the Arm by the motor, if splined connection is loose and Arm wants to become disconnected, it will...then, one may find themselves looking for the Wiper Arm at the side, or middle of the road...in the rain...DON'T GET RUN OVER BY TRAFFIC! 

Installing Wiper Arm:  Variations in the splining of the Wiper Arm Cup in Arms from various manufacturers can also be seen in the two pictures above...typically, there are more splines on the Drive Bushing than Cup, so this allows installer some angular options in the Park Position, when installing a Wiper Arm back onto the Drive Bushing.  Technique should be to hold the Arm at the preferred Parking position angle on Windshield, then fold the Cup open against the beefy spring (if the "Removal Tool" is not already doing that) to align it with Drive Bushing, and vary the angular position until the nearest mating point/(spline) is found, then pressing the Cup home onto the Bushing with authority...a couple of measured, gentle taps would not be out of place to take up any slop in an old, worn spline joint

Currently available replacement Drive Bushing, which certainly looks like brass...installed with a hammer...the external Splines on the Driveshaft cut into the soft brass...I don't like the hammer part so much, but it looks like installer was successful here (a helper backing the shaft under Dashboard up with a counter-mass against the Hammer impacts, is a very good idea, and recommended!)...a drop of Loktite to wick into and fill any spaces between the two to further secure the connection might be a good idea too...

Drive Bushings are an Interference Fit! 

Tip to help with installing one of these replacement brass Drive Bushings, which can be difficult and stubborn since they have a plain, undersized ID surface when new, and are an Interference Fit!  [I have seen the term "miserable" used...]: 

Installation tip on Faceplant! by Mike P:  "Tap it on to give you marks, then file the grooves by hand."

My response to Tip: 

"This is a brilliant Tip! New replacement bushings have a plain, ID which will be bear toinstall without this trick (even when supporting the Wiper Driveshaft from below so it can be pounded on with impacts from a hammer)! ...but adding the grooves based on witness marks will greatly help! 

I give you high points for this Tip!"


My response to another Faceplant! installer who questioned the replacement Bushing being the right part, because there were no internal splines:

"Replacement Bushings do not have splined ID because they are sized to be an INTERFERENCE FIT, and so intended to be pressed-on with a fair level of force...so you MUST support the shaft well from below when doing this...and you can use hammer impacts...but depending on the amount of interference, you may feel this may be more force than you want to use...so a trick is to just put bushing on lightly and tap it enough to get witness marks from splines, then remove it and file SLIGHT but accurate splines into (at least some) of the ID at the witness marks to reduce the interference a bit (not too much, it MUST still be an interference fit!), to help with final installation...I would say file, then trial-fit (leaving SOME interference!), then file some more, and trial-fit...this is a tricky process which should be repeated until you are satisfied you can finally force the bushing on with good contact (if I was replacing a Bushing, I would use this method, and for final installation, apply an anaerobic threadlocker to take up space between shaft and bushing, and permanently "seal and glue" it on, as I tapped it home, well supported from below!) ...don't forget, this bushing transfers fairly high forces in service! Please post pix of your results and comments! Good Hunting"


Link to Reference Information, Wiper Drivebushng Dimensions


Other Creative and Non-Original Repairs:  

A somewhat rustic "setscrew repair" undertaken after an Arm was lost...I saw this in my surfing around the net...it looks like it would work, but I don't like it so much as it is pretty ugly, and it seems that it would significantly weaken the small Driveshaft below Bushing as the size of the setscrews is approaching the diameter of the splined shaft.

The author came up with this solution some years ago, for keeping the Anco Standard Replacement Arm (See info on this below) firmly attached to Wiper Drive Shaft, which is arguably less rustic and (slightly) less ugly than the one above (...so says he!)...  A very carefully hand-drilled and tapped arrangement with a SS 6-32 screw installed keeps the Driveshaft and Wiper Arm positively united:  

This is a workable repair which leaves all splining of the Driveshaft intact, unweakened, and able to transmit the operating torque, but not recommended for the faint of heart...if the drillbit was not down the center or Tap were to break during the operation, it would render the assembly into scrap, and increase the scope of the repair project, and number of expletives uttered, a lot....



Wiper Arm/Post Repair

SW-EM Tech Article:  Windshield Wiper Systems


Reference Information:


Anco No. 41-01 Original Equipment style Standard Wiper Replacement Arm.  This is not a specific endorsement, but the author has found quality to be good, cost to be reasonable and it to work satisfactorily.  Other Manufacturers probably produce similar parts: 

I have found the this part works well on the 122 and 1800 application when paired with 11 inch wiper Blades for the 122 or 13 inch Blades on the 1800.  Note that Blade angle with respect to Arm is adjustable (A), and that included is a Drive Bushing where mating hole is off-center, which allows a setscrew securing arrangement (B).  This might be just the thing for a damaged Drive Shaft! 


Wiper Drivebushing Dimensions: 


OD of Driveposts are slightly conical by my measurement! 
Don't forget...Drive Bushingare an Interference Fit!  ...see above! 


Drive Bushings with a set-screw are a great solution if splines on drive-shaft are damaged or there is an issue with the Interference Fit! This damage is rare, as the Bushing is typically of softer material, but in some cases may be a good repair option! 

Source:  https://www.macsautoparts.com/ford_thunderbird/ford-thunderbird-wiper-pivot-repair-kit-4-pieces-1955-60.html?fbclid=IwAR1nDiZrMn5erFbwbVxNMjrNXRWvGHrepoTimvCskkR84tfBW0o7oUnUPFk# [I have no relationship with this outfit other than to make others aware of its existance!]


Another Drive Bushing Option I ran across...this bushing seems to have more options, which might prove handy when dealing with a damaged Driveshaft: 

Source:  Carbuilder.com/uk  Link


Mechanical play in the Wipers

Slop or lost-motion in Wiper Blades can develop as the mechanism wear in general, but as a rule, the square, swagged Drivepost to linkage connection should not, this suggests Wipers were heavily loaded, or even locked in-place (by ice). Below are two examples of the damage which can be cause by locked Wiperblades...the first on a 122 Gearbox drive, and the second on an 1800 Cable-on-Cam drive. 

122 Gearbox type Wiper Drive Mechanism with damage:  

The Gearbox type drive is not immune from damage by a frozen Wiper Blade, or even just moving large amounts of heavy snow and long-term wear.  Here the Segment Gear Shaft has worn slop into the square drive linkage hole.  To prevent this kind of damage, it's quite important assure Windshield Wipers are not bound by ice or anything else, and free to operate!  If this sort of damage occurs, author recommends TIG welding across the gap of displaced metal. since fixturing the assembly to redo the peened and displaced metal of the original is beyond to shop possibilities of a casual mechanic, especially with the assembly attached to the Gearbox. 
Picture credit:  R. Watson and used with his kind permission.

1800 Wiper Linkage Repairs [copied from SW-EM Service Notes Page, Body]

[From E-mail response to Oliver B. regarding "play in the 1800 wiper system". 


I suggest you try to figure out just exactly what the problem is with your cable wiper system...I don't actually think either system [122 gear type, 1800 cable type] has any particular inherent weaknesses other than wear induced slop after they've made about a million or so wipes...and can you blame them at that point? (And I doubt the gear type is much better at that point either!) I have noticed that the double "D" shaped shaft of the cable type going into the pulley overpowers the matching hole in the pulley and develops a fair amount of slop...this is in fact the situation on my '66 1800...this does seem to be a weak link, but I plan to have the shaft (carefully) TIG welded onto the pulley (instead of replacing the whole mechanism) whenever I get to removing the assembly...as you know, I'll be putting that off for as long as I can!!!...in fact, that is one reason I came up with the intermittent wiper controls for the different vehicles (see SwEm kits)...it further minimizes the rate at which the wiper system mechanics wear. I suggest you consider this same welding fix, if the worn double "D" hole condition exists on your car. 

1800 Cable wiper linkage showing square drive double "D" shaft and distorted hole in pulley (Photoshopped in - I didn't feel like crawling under the dash of my 1800 for a real pic, so I went the lazy route...)


Alternate Wiper Arm to Drive Post Securing:


Volvo did not manufacture Wiper Arms, but fitted assemblies from manufacturers who specialized in producing them.  Here is another style which was encountered.

Constant Busch in Britain recently showed this Wiper Arm in a FP post.  Notice the Philips head screw, not protruding into the Wiper Drives Post, but a look underneath shows it is still securing the Arm, by way of what the manufacturer calls a "wedge lock". 


Pictures by Constant Bush and reposted with his kind permission.   


Question:  What does the Philips flathead screw go into?
...it's certainly not going into the Drive shaft like my groovy solution shown above!



Answer:  Into a threaded plate which clamps onto the Drive Post!


A request for manufacturer's info shows this Wiper Arm is Made in England, by the company Tex...they have web presence and Arms are still available. This looks like a good option for a loose Drive bushing!


"Tex" British Manufacturer:  https://www.motoringclassics.co.uk/classic-car-parts/wiper-arms?fbclid=IwAR3o0964nhdj4oZfg7BCqk_QtNhVhpEdnm61gRMUUUf-mswcPWF3A2QiGXQ


From the Tex Product Details:  "The TEX patented Wedge Lock design allows replacement wiper arms to be fitted to worn wiper drive bosses which would otherwise be unsuitable for push-on heads."  [This design looks effective!]


Scratched Windshield:

My response to a FP posting of what to do about a heavily scratched Windshield: 

" What that [Windshield polishing] outfit is telling/selling notwithstanding (and I invite them so prove me wrong!), only the slightest scratches and pits can be removed...so with a major arc-scratch from contact of the Bladeframe with glass, it's most probably time for a Windshield (and Gasket!) replacement (inspect and correct gasket seating area for rust!).
That makes the point about never running the Wipers dry, and NEVER, EVER, EVER letting the Blades deteriorate to a point that the Bladeframe touches the glass! May "Shame and the Wrath of Odin" be upon the slacker individual who allowed that!
If a Blade deteriorated like that on the road, and I needed the Wiper, I would rather pull that Wiperarm off, than allow contact...and if it was the drivers side, I'd swap the Blade over from the Pass side...yep, that's what I'd do!  " 


Windshield Washer Nozzles:

Trico supplied Washer Post showing a single Nozzle.  Some configurations had one centrally located on the hood with two Nozzles, the 544s (and some early 122s) had two separate posts with single Nozzles, next to the Wiper Posts. 



External material attributed. This information is Copyright © 2017-2023.  Ronald Kwas.   The term Volvo, Anco, Trico and Tex are used for reference only.  I have no affiliation with any of these companies, other than to try to keep their products working for me, help other enthusiasts do the same, and also present my highly opinionated results of the use of their products here.  The information presented comes from my own experience and carefully considered opinion, and can be used (or not!), or ridiculed and laughed at, or sent to Sweden to your uncle Olaf for review, at the readers discretion.  As with any recipe, your results may vary, and you are, and will always be, in charge of your own knuckles, and future!


You are welcome to use the information here in good health, and for your own non-commercial purposes, but if you reprint or otherwise republish this article, you must give credit to the author or link back to the SwEm site as the source.  If you donít, youíre just a lazy, scum sucking plagiarist, and the Boston Globe wants you!  As always, if you can supply corrections, or additional objective information or experience, I will always consider it, and consider working it into the next revision of this article...along with likely the odd metaphor and probably wise-a** comment. 


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