Windscreen wiper park position adjustment?

[Eskozki]

Hi,

During summer I noticed my windscreen wipers will go lower than where they are stopped. Is there a way to adjust the park position? Now they park pretty high up. During wiping the lowest point they go is what seems to be the correct park position. Thanks for the help! The car is a -87.

[944 Ecology]

Originally Posted by Eskozki

Hi,

During summer I noticed my windscreen wipers will go lower than where they are stopped. Is there a way to adjust the park position? Now they park pretty high up. During wiping the lowest point they go is what seems to be the correct park position. Thanks for the help! The car is a -87.

https://www.youtube.com/watch?v=qRkrdlIx9LE&ab_channel=ProblemSolverGarage

It's a real pita, so make sure that it is properly readjusted befor reinstalling.

[Eskozki]

Thanks for the video, all that just to adjust the position of the wipers... Now I understand why the PO settled on them being slightly off

I Think i'll live it that aswell for now, thought it would be a lot easier.

[89-944NA]

I hope you did the most obvious thing and removed the wiper arms, cycled the motor, then reinstalled the arms in the park position. With the arms being aluminum it could also be that at some point in time they weren't properly tightened and the steel shaft rotated in the arm enlarging the hole. Back in the stone ages when I got my first 944, I had the same problem, tried the first fix (removed arms, etc), wipers worked as they should, but when I turned them off they went back below the "park" position. Removed the arms again and, shimmed the holes until I could get new arms......and they worked perfectly

[Monkey Wrench]

i ran into a problem like that with some other car, where the serrations in the arm or the part they fit onto were wrecked up and a drop or two of Loctite or JB weld fixed it. i If it needed to come off again it could perhaps need a bit of heat with a torch. I dont remember more about that issue, although it sounds mickey mouse, I think it it worked fine and never became a problem later. I probably could have hunted down new replacement parts instead but I think it just got resolved that way and then lasted fine.

I dont know if there is anything weird about how the wipers in this particular car are held on but most cars I've sen work the same..

I think because both parts are rough and if it's clean that will work, although it is not exactly a puritan approach.

I had ( volvo) wipers start running slowly and found the magnets in the motor had come loose from the case and then dragged against the rotor. the motor still worked but slowly. gluing the magnets back inside the motor case so they could not suck onto the armature and restrict it's movement worked fine , again JB weld..

I've seen the same thing happen with door window motors, funny they can still run like that with the magnets detached. the ones I saw had a bit of tell tale wear on the armature itself, and the magnet from rubbing.. think the case has two magnets and if one comes loose the other still can't move far from it's original position, but it sticks to the armature with the magnetic force it has..

If you ever have a very slow DC motor of this age, I'd look for that situation.

might have to have them side by side to say for sure, I think this might actually be the same motor as used in a Volvo. one might find it's used on lots of cars?

[Eskozki]

The wipers go lower to where they park during wiping, this makes me believe that if I remove them and cycle the motor and then put them to a proper park position they would hit the bonnet as during the wiping cycle they would go below the new park position. During wiping the lowest point looks to be the correct position for parking.

I also found that intermittent doesn't work, propably it is the thumb wheel thing in the cabin that is broken. The relay had something to do with the park position if I understood correctly but i wasn't able to test if the relay.

[Monkey Wrench]

Do 944's have a delayed wiper feature ? ( for light rain) I think it became popular around the time my 85 was made or maybe shortly after .. I recall a story about how some guy invented it and patented the idea.

perhaps there is a ( second? ) delay relay for them to return to park?

how does this delay feature work? I'm suspecting it is a circuit where a capacitor is charged up or something similar and maybe the cap goes bad? It might be interesting to have a closer look into those units to see if there is a capacitor that can be replaced..

I'm imagining it works by current flow reaching a capacitor with current flow restricted trough a resistor so the cap takes maybe a second or three to charge and then when it reaches a certain voltage it allows a transistor to switch, or the voltage reaches such poin tit can power up a little relay coil for s et of contacts.. something like that..

thus delivering that delayed voltage.. The cycle would need to repeat endlessly for delayed wipers but not for a delayed park position, that would be a one time delay..

My 88 volvo also has a delay like this for the interior light ,and for the power antenna, and it has delayed wipers.. I don't know if my 944 has that. my 88 ford van does not have delayed wipers.. some car companies were slower than others on the uptake of this invention.

I've seen old delay mechanisms in old machines that were sort of like a clock with mechanical parts, those were expensive to produce, but by around 85 this was done with electronics and no moving parts other than the contacts. If park is delayed after switch off, perhaps there might be a separate relay for that responsibility.

if delayed wipers are not a stock feature I imagine some have added it. someone else here is going to know this stuff.

I can see how putting the arms on in the wrong spot might cause mechanical damage. some care to make sure you know where the park position is before installing the wiper arms will prevent that. if you just installed the arms and are confused, I'd remove the arms until the park position is determined because you could crash those parts by making that mistake.

I'm smiling about the use of the term "bonnet", I know it's a hood, just not a term I hear used very often in these parts ;-)

[djnolan]

Eskowski, if the wipers don't park at the bottom of the sweep they may have been taken apart to replace or rebuild the motor or something. Also if the intermittent isn't working you may need a new relay. Ask me how I know (oh my aching back) ...

[originalowner]

Originally Posted by Eskozki

The wipers go lower to where they park during wiping, this makes me believe that if I remove them and cycle the motor and then put them to a proper park position they would hit the bonnet as during the wiping cycle they would go below the new park position.

You are correct. Do not re-index the blades. The motor is rebuilt incorrectly.

[Monkey Wrench]

I think what likely happened here is that the wipers were turned on, or left on, the wipers were restricted by ice. the motor tries to move the blades up, and the arms are frozen, then the serrated part moves and jumps a "tooth"

After that "event", the arms are trying to move down too far because they slipped out of position.

the answer is to reposition the arms and maybe you need to do something about the wear from the tooth jumping. you might add a shim or use something like locktite or JB weld.. maybe the nut just needs to be tightened up and it will hold You can examine the condition of the ribbed parts that are supposed to retain them, it may be likely that only one slipped.

in that video he shows the three contacts and there is sort of a cam there, i believe that is to do with the positioning. I doubt that anything moved out of position there but that governs the positions and it's there to turn the motor off once it reaches it's position.

if you shut the wipers off, they don't immediately stop , it is designed to always stop them at the bottom of their "stroke" this is the basic function of the switches, there may be a second one for the lower park position. It shows three contacts.. You can probably sort of reverse engineer that if you have it apart, to understand it better.

if there is a delay and then it moves to " hidden" then a delay relay is probably also involved.
I believe that motor always runs in the same direction.

I do not think anything is assembled improperly otherwise. if you think about it if you wanted to work on it than you'd need to remove the wipers and the position could be lost when putting them back. It would be impossible to move the relationship of the parts in the gear case without removing the arms first.

I do think it's a good idea to pull this motor apart just to lubricate it and check out the bushings , check out the brushes, clean the commutator and the contact points. look if it's rusty in there..

That's for reliability, because if your wipers die and they are needed the car can be un-driveable, That can happen during driving and this can cause an accident by blinding the driver, so it is a very important part and we all tend to not think about much about it's importance until we see a failure.

if you don't want replace the arms and you have wear there from it slipping you can use JB weld but then after if you ever want to remove them again you will need to heat them up with a blowtorch to burn up or soften the JB weld. Best of course to replace them if they are bad, if you dont have the parts to swap, you might instead try adding a shim, a slice from a beer can, will probably work .

during winter, try to shut your wipers off before you turn the car off and then you wont get in and start it up with them on, causing this situation. You will then be more likely to free them up before you turn them on, circumventing this situation.


the other way this can be caused is if the nut that holds the wiper arm on comes loose. Ive seen wipers that had some freeplay between the inner and outer splines. If those parts are nto locked together then when the wipers are running the splines can wear out by the parts constantly moving relative to each other. The nut is supposed to lock the two together and remove any freeplay.

[djnolan]

Hello, I reviewed the video, the dude is very crafty and does a really nice job. I thought I would amplify a couple of key points.

At 16:51 when he marks the position of the wiper arm on the frame, this is crucial to the park position. Also notice the wiper arm is aligned straight with the frame. Suggest running the motor when connected to the car and park the motor and check this alignment before installing back in the car.

Also at 22:34 the little rubber things help keep steady brush pressure against the armature, the brush plate suspension. They are old and weak, and NLA so they could be replaced with rivets or screws. If this isn't done the rebuild won't last.

Also at 30:10 when he puts the motor housing back together, de-grease and seal around this thoroughly with silicon RTV to keep water out. Put RTV on the flange before putting it together, and coat RTC around the outside once together. Do not drill the hole for water drain, this will just make things worse.

[Monkey Wrench]

with brushes like that , Ill often just find a paperclip ( or two) and bend the very end of the wire into a U shape, use that as a tool to pull the brushes away from the armature, then remove the armature. ill usually try to snag the wire that is attached to the brushnear the brush, and pull there..

a fast way to mess up little motors is to fail to remove the brushes and pull the armature with them installed.

You can't get the motor back together without either removing them or pulling them away from the armature.

if brushes are worn you can often take them from another application and if you want to resize them they file very easily. It's like taking a file to a graphite pencil, so you can make them smaller very easily with a bit of care rather than hunting for specific proprietary brushes.

[djnolan]

some motors have holes in the brush apparatus for paper clips.

However on these motors the rubber thingys (brush plate suspension) need to be replaced or changed out to screws or rivets if the rebuild is to last. (PS I credit this idea to a local rebuilder and is not my idea)

The rebuilt motor I got online didn't last a month or two. I took it to the local rebuilder and he returned it with the brush plate riveted where the rubber thingys once were. So far it is going on 5 years and still working.