Rear wiper is very slow
11-23-2003, 07:31 AM
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Rear wiper is very slow
I obviously have a feed to the rear wiper motor, but it operates so slowly that it takes a good 2 minutes to do one full sweep and struggles to return to the vertical position.
Are the motors unservicable when they get like this, ie. could it be lubricated? Or is a new motor called for?
Any btdt would be appreciated.
TIA
Are the motors unservicable when they get like this, ie. could it be lubricated? Or is a new motor called for?
Any btdt would be appreciated.
TIA
11-25-2003, 02:51 PM
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Update.
I cleaned the conectors on the motor and if anything it is worse.
Infact, it no longer works at all! If I switch it on and assist the wiper arm by hand, it does move, but not much.
If I check breakers yards for a replacement, which models can I look at? ie. Is it the same motor on later 911's or must I source one from an SC/Carrera?
Alternatively, is it possible to strip down the motor and lubricate it etc.
Any BTDT?
Thanks in advance for any help/suggestions.
Mark.
I cleaned the conectors on the motor and if anything it is worse.
Infact, it no longer works at all! If I switch it on and assist the wiper arm by hand, it does move, but not much.
If I check breakers yards for a replacement, which models can I look at? ie. Is it the same motor on later 911's or must I source one from an SC/Carrera?
Alternatively, is it possible to strip down the motor and lubricate it etc.
Any BTDT?
Thanks in advance for any help/suggestions.
Mark.
11-25-2003, 03:55 PM
#3
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This is a good opportunity to remove it and replace with a plug. I don't like rear wipers on 911s because:
1. The detract from the lines of the car
2. They add weight and another thing to break (witness your post)
3. They are unnecessary, since the airflow on a 911 keeps the rear window clean from rain or snow at any reasonable speed (especially with defroster)
1. The detract from the lines of the car
2. They add weight and another thing to break (witness your post)
3. They are unnecessary, since the airflow on a 911 keeps the rear window clean from rain or snow at any reasonable speed (especially with defroster)
11-25-2003, 05:07 PM
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Sorry if my last post was too preachy! I hope someone can provide you with the info about the motor.
Good luck,
Grant
Good luck,
Grant
11-25-2003, 06:44 PM
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Hey, no probs. I didn't interpret it as preachy. Infact, you may have a point about it spoiling the lines.
I just may consider removing it. As it happens, I never use the rear wiper on my quattro as the wind keeps it clear like you say it does on the 911. It is obviously handy to clear standing water before moving off though.
Also, remember that I am in the worlds rain capitol!
I just may consider removing it. As it happens, I never use the rear wiper on my quattro as the wind keeps it clear like you say it does on the 911. It is obviously handy to clear standing water before moving off though.
Also, remember that I am in the worlds rain capitol!
11-29-2003, 03:54 AM
#6
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Mark sP,
First let me say that I have no experience with the rear window wiper motor as I have an '86 Carrera sans rear wiper.
Next, let me advise that you disconnect power to that wiper motor AS SOON AS POSSIBLE (ASAP)!
Something is not right. Your primary concern here is not to set the car on fire or burn up/smoke critical or expensive wiring due to some sort of malfunction associated with that motor.
The fact that you haven't had its fuse blow is definitely in your favor but don't get complacent!
At 2+ minutes for a single sweep something is very, VERY wrong!
You may have already done so (and if so I apologize for the urgent tone of my message) but if not I'd STRONGLY recommend that you immediately check the following:
1) Check the fuse that controls the rear wiper motor's circuit (per owner's manual and supplements or other reliable sources). Make sure that it's the amperage rating specified for that circuit and your car. Anything higher is asking for a fried circuit or possible fire.
2) Make sure that the motor is indeed controlled by the designated fuse and electrical circuit. Pull the designated fuse and make sure the rear wiper motor DOES NOT work! If it still operates, something (electrical power (positive) cross-feed or previous owner's re-wiring experiment?) is doing something for you that you definitely don't want!
3) It is entirely possible that the motor may just be at the end of its life and motors in that condition can do weird things. The last thing you want is a a sudden high current draw on an unprotected circuit as would be the case if someone wired it directly to a voltage source with no fuse protection or to some other voltage source that, while fused, was not intended to draw the current the wiper motor could require in either a normal or failure mode .
Sorry for the alarmist tone and I definitely don't mean to insult you or make more of this than there really is. It's just that the symptoms you reported raised all kinds of RED FLAGS in my (admittedly paranoid) book!
On the calmer side of things (once the above has been checked) see if the motor mounting has shifted or if any drive shaft bushings/seals (on the cowl pass-through - if any) have deteriorated to the point that the drive arm is binding in some manner.
Check this with the rear wiper arm removed and observe the rotation speed of the drive shaft itself. This would be considered a 'no-load' scenario for the motor and if it doesn't work here it won't work under load, I.E. wiper installed and in contact with the rear window.
If it works in the above setting and has a properly fused circuit with proper voltage but fails to work once a load is placed on it (wiper installed and in contact with window) check the wiper arm itself to insure that it's not bent to the point where it's exerting some 'gorilla grip' type force on the window. The wiper arm should press down firmly on the window but still be willing to move - just like the wipers on the front windshield.
If things don't work after doing the above you probably just have a tired motor or one whose positive voltage supply or ground won't support the amount of current it needs to receive from/return to the battery. A good shop could verify this quickly and cheaply as you can point them to exactly what you need tested.
As always, try your best to make sure you don't buy something you don't need and that doesn't fix your problem.
Sometimes you have to spend some bucks (I HATE that ;-) ) but in the end it's for the best if you can't safely find the answer and safety is KEY.
Good luck and I hope you post your resolution if you get the wiper working or not. Your experience helps us all and, after all, that's exactly what makes Rennlist the place it is!
As for rain, I thought I lived in a soup bowl! I checked your stats and feel bad about not sending you a towel! I truly hope to get your way sometime in the future as I've always dreamed about touring the areas you must drive through daily!
Barry
First let me say that I have no experience with the rear window wiper motor as I have an '86 Carrera sans rear wiper.
Next, let me advise that you disconnect power to that wiper motor AS SOON AS POSSIBLE (ASAP)!
Something is not right. Your primary concern here is not to set the car on fire or burn up/smoke critical or expensive wiring due to some sort of malfunction associated with that motor.
The fact that you haven't had its fuse blow is definitely in your favor but don't get complacent!
At 2+ minutes for a single sweep something is very, VERY wrong!
You may have already done so (and if so I apologize for the urgent tone of my message) but if not I'd STRONGLY recommend that you immediately check the following:
1) Check the fuse that controls the rear wiper motor's circuit (per owner's manual and supplements or other reliable sources). Make sure that it's the amperage rating specified for that circuit and your car. Anything higher is asking for a fried circuit or possible fire.
2) Make sure that the motor is indeed controlled by the designated fuse and electrical circuit. Pull the designated fuse and make sure the rear wiper motor DOES NOT work! If it still operates, something (electrical power (positive) cross-feed or previous owner's re-wiring experiment?) is doing something for you that you definitely don't want!
3) It is entirely possible that the motor may just be at the end of its life and motors in that condition can do weird things. The last thing you want is a a sudden high current draw on an unprotected circuit as would be the case if someone wired it directly to a voltage source with no fuse protection or to some other voltage source that, while fused, was not intended to draw the current the wiper motor could require in either a normal or failure mode .
Sorry for the alarmist tone and I definitely don't mean to insult you or make more of this than there really is. It's just that the symptoms you reported raised all kinds of RED FLAGS in my (admittedly paranoid) book!
On the calmer side of things (once the above has been checked) see if the motor mounting has shifted or if any drive shaft bushings/seals (on the cowl pass-through - if any) have deteriorated to the point that the drive arm is binding in some manner.
Check this with the rear wiper arm removed and observe the rotation speed of the drive shaft itself. This would be considered a 'no-load' scenario for the motor and if it doesn't work here it won't work under load, I.E. wiper installed and in contact with the rear window.
If it works in the above setting and has a properly fused circuit with proper voltage but fails to work once a load is placed on it (wiper installed and in contact with window) check the wiper arm itself to insure that it's not bent to the point where it's exerting some 'gorilla grip' type force on the window. The wiper arm should press down firmly on the window but still be willing to move - just like the wipers on the front windshield.
If things don't work after doing the above you probably just have a tired motor or one whose positive voltage supply or ground won't support the amount of current it needs to receive from/return to the battery. A good shop could verify this quickly and cheaply as you can point them to exactly what you need tested.
As always, try your best to make sure you don't buy something you don't need and that doesn't fix your problem.
Sometimes you have to spend some bucks (I HATE that ;-) ) but in the end it's for the best if you can't safely find the answer and safety is KEY.
Good luck and I hope you post your resolution if you get the wiper working or not. Your experience helps us all and, after all, that's exactly what makes Rennlist the place it is!
As for rain, I thought I lived in a soup bowl! I checked your stats and feel bad about not sending you a towel! I truly hope to get your way sometime in the future as I've always dreamed about touring the areas you must drive through daily!
Barry
11-29-2003, 08:58 AM
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Thanks for the 'Heads Up' Barry.
Go right ahead and be as alarming as you like. We are two peas in pod obviuosly. I would much rather be alarmed than understimate a potential problem.
I am heading out to the car now to perform the checks that you mentioned.
I will of course report my results/discoveries asap. I agree that is what makes this board great. Thanks for the replies guys.
ps. Any spare towels that you have would be gratefully accepted. Not only do we get loads of rain here, but I chose a Targa! LOL
Mark
Go right ahead and be as alarming as you like. We are two peas in pod obviuosly. I would much rather be alarmed than understimate a potential problem.
I am heading out to the car now to perform the checks that you mentioned.
I will of course report my results/discoveries asap. I agree that is what makes this board great. Thanks for the replies guys.
ps. Any spare towels that you have would be gratefully accepted. Not only do we get loads of rain here, but I chose a Targa! LOL
Mark
