Sloooowwwww rear window...help, please?

[Wishmeluck]

84 Bronco....Rear window goes up and down painfully slow and stops partway in both directions. I can always pull/push it up/down the rest of they way by turning the t/g key.

It has a new motor, gears/tracks have been cleaned, lubed and it has new little glide thingys in the tracks too. The dash switch has been cleaned and the grounds behind the dash were all cleaned and renewed too.

Heres my conundrum:

- If I give it juice straight from a battery to the window motor on the window side of everything it shoots up and down great.

- If I hook wires up and give it juice so it works through t/g key ONLY the window will go up pretty well, but down is super slow and gets stuck about halfway.

- If I hook wires up and give it juice so it works the the dash switch ONLY the window goes up halfway and gets stuck, and goes down painfully slow.

I tested each scenario and get a full 12v when the switches are flipped to wherever power needs to go, and just to make double sure I even ran a dedicated 12v wire to the connectors and tried that too.

Since I was getting 12v everywhere, I thought maybe it was poor grounds. So, I also threaded the ground ***** hole in the drivers tail light area for a dedicated ground close by. One switch at a time nothing changed no matter the power/ground source combination.

Im trying to keep it as stock as possible and really dont want to admit that maybe after 40 years maybe the switches are just getting worn. Anyone have any suggestions I may have missed or overlooked aside from the switches themselves?

 

[johnnyreb]

84 Bronco....Rear window goes up and down painfully slow and stops partway in both directions. I can always pull/push it up/down the rest of they way by turning the t/g key.

It has a new motor, gears/tracks have been cleaned, lubed and it has new little glide thingys in the tracks too. The dash switch has been cleaned and the grounds behind the dash were all cleaned and renewed too.

Heres my conundrum:

- If I give it juice straight from a battery to the window motor on the window side of everything it shoots up and down great.

- If I hook wires up and give it juice so it works through t/g key ONLY the window will go up pretty well, but down is super slow and gets stuck about halfway.

- If I hook wires up and give it juice so it works the the dash switch ONLY the window goes up halfway and gets stuck, and goes down painfully slow.

I tested each scenario and get a full 12v when the switches are flipped to wherever power needs to go, and just to make double sure I even ran a dedicated 12v wire to the connectors and tried that too.

Since I was getting 12v everywhere, I thought maybe it was poor grounds. So, I also threaded the ground ***** hole in the drivers tail light area for a dedicated ground close by. One switch at a time nothing changed no matter the power/ground source combination.

Im trying to keep it as stock as possible and really dont want to admit that maybe after 40 years maybe the switches are just getting worn. Anyone have any suggestions I may have missed or overlooked aside from the switches themselves?

 

[johnnyreb]

Have you looked at the wires good? Look for blue color. Like maybe they got hot and looseing their continuity. Another thing that could cause it is --check the hot wire on the starter----if its loose. I found out the other day on mine-- When your dealing with wireing---it can get aggervated. Good look. Check the motor out good too. You can get BAD NEW PARTS. I went through 5 new starters in one day--from the parts store.

 

[lynchsg]

LMC Truck sells new OEM style dash switches. Check the condition of the plug going to the dash switch and it's wires for overheating.
In the tailgate key switch, clean the contacting surfaces with emery strip abrasive cloth that get dirty or corroded. Also check the switch wiring connections for corrosion etc.
There are a couple of in line permissive tailgate switches that are part of the circuit. I by-passed mine because of problems with them.

 

[chrlsful]

rigs this old I all ways ck GROUNDS.
Like any thing else, start @ 1 end (the
v e r y begining) and end @ window. Test
lght 4 continuity, multi meter for power level ?
Test either side of switches. Everything . . .

 

[L\Bronco]

84 Bronco....Rear window goes up and down painfully slow and stops partway in both directions. I can always pull/push it up/down the rest of they way by turning the t/g key.

It has a new motor, gears/tracks have been cleaned, lubed and it has new little glide thingys in the tracks too. The dash switch has been cleaned and the grounds behind the dash were all cleaned and renewed too.

Heres my conundrum:

- If I give it juice straight from a battery to the window motor on the window side of everything it shoots up and down great.

- If I hook wires up and give it juice so it works through t/g key ONLY the window will go up pretty well, but down is super slow and gets stuck about halfway.

- If I hook wires up and give it juice so it works the the dash switch ONLY the window goes up halfway and gets stuck, and goes down painfully slow.

I tested each scenario and get a full 12v when the switches are flipped to wherever power needs to go, and just to make double sure I even ran a dedicated 12v wire to the connectors and tried that too.

Since I was getting 12v everywhere, I thought maybe it was poor grounds. So, I also threaded the ground ***** hole in the drivers tail light area for a dedicated ground close by. One switch at a time nothing changed no matter the power/ground source combination.

Im trying to keep it as stock as possible and really dont want to admit that maybe after 40 years maybe the switches are just getting worn. Anyone have any suggestions I may have missed or overlooked aside from the switches themselves?

Hey wishmeluck!
Nothing more frustrating than electrical faults.
Sounds like 2 issues.
1st you have circuit resistance somewhere, second a window track adjustment issue.
Voltage loss will slow it down and drag will raise the current flow aggravating the resistance issue.
Start with the resistance first.
Hook everything up like it should be, factory everything, then measure the voltage across the motor while its running. (Both meter leads at the 2wire plug at the motor, you will need help.) Activate it from the dash switch.
Watch the voltage when it slows or stalls.
If its less than battery by more than a volt (when the symptom is there) you have too much loss.
Then measure from the positive wire at the motor to the battery positive post and redo the test. (Run it till it drags)
Repeat for the ground side.
If you find a big loss on either side, keep testing that side while moving your lead to connectors along your circuit, always moving toward the battery. Never take the lead off of the battery post on the side you are testing. (Positive to positive, or negative to negative.) only move the lead thats in the harness and make your way to the battery post.
Its called voltage loss testing and if done correctly, it never misses.
Hope that helps.
Good luck.
cheers

 

[Tiha]

Did 84 have the safety switch?

That was a huge source of resistance and slow window movement.

But ditto on testing. You have a bad wire or ground somewhere. Key switches wear out too.

 

[goodO1boydws]

I'm with L/Bronco.
If, as you wrote, the motor operates the window FINE-both up and down when you are supplying battery power to the window motor directly, that pretty much eliminates track alignment/adjustment as being much of an issue, but every little bit of lost efficiency hurts. My personal guess is that its liable to be losing a little bit of voltage along every section of the circuit, (old wires and switches, weak connections, marginal grounds) and its a cumulative voltage drop rather than coming from a single culprit. Do you happen to be where much salt is being used on the roads? That is a very common cause for gradually developing poor connections on older vehicles if they are driven much or not. The salt works its way in and never gets completely out, causing progressive oxidation/corrosion. This sort of thing often shows up first with exterior lighting circuits as their wires, connectors, and sockets are more exposed.

 

[Wishmeluck]

I did some more research and I think its actually the window motor itself. I went to a local pick and pull and pulled a couple of other key switches, wired them up, and got the same results, fast up/slow down. I thought no way its the same with all three switches, its gotta be wiring. I think my little battery is running a little low from all the up/down ive been doing with the window and I started to notice the window was now going slow all the way back at the motor. Its also not the original window motor..doesnt even look/fit like the original. I mean, it goes up and down but only two of the holes line up and it looks like driver/passenger door window motor. Gonna get that out and get the right one in first. I figure if an aftermarket heater blower motor cant warm up the cab but an original motorcraft can, maybe the rear window motor is the same and cheap china stuff just isnt gonna cut it. Thank you everyone for all your suggestions and will post up results when I get it swapped...

 

[Tiha]

Yeah that doesn't like the correct motor. I hope that fixes it.

Hooking directly to the motor for testing is great but it can be deceiving because it is able to send a lot more current to the motor and does not replicate your actual battery voltage or line loss.

 

[Wishmeluck]

It was 100% the motor. I didn't want to wait a week for delivery so I pulled a window motor from a 92' f150 (passenger side is a direct fit), tested it at the yard, and brought it home. Window goes up/down flawlessly with both switches. Picture is a side by side of the one available at parts stores they SAY will work (on the rhs), but I'm not sure how they can claim that when all the holes don't even all line up. Anyways, thanks again for all your help...on to body mounts!! (When it stops raining).

 

[lynchsg]

Only a slight motor winding size difference, too!

 

[Tiha]

Great visual reference, Thank you for the follow up.

 

[johnnyreb]

Their was a article--I think it was on hear--where a guy took that cover off--cleaned up everything and replaced(I think ball bears) put it back together and he said it ran like a new one. I,ll find out before long. Today I got the gas leak stopped on the Holley and I,m waiting for my friend to stop buy. So we can try it out. Then I.ll take care of a couple of small things. One is the slow tailgate and one dim park light on the front. I put all new grounds--heavy duty and light sockets--might be the china bulbs. Coming a rain now--so I,ll work on restoring my gun. After buy 6 JC HIGGINS---I learnt alot about them.hahaha. I,m almost a expert now.haahaha

 

[goodO1boydws]

What johnnyreb is referring to are the polyurethane "rollers" that are in the gear case. They are 3 in number and about 1/2" diameter x 3/8" tall.

The original-type rollers are made of that material so they will shred if the window glass encounters too much resistance when closing a window.
ITS FOR A VERY GOOD SAFETY REASON.
If they DON'T shred, when a kid has his head through the open window and triggers the window switch to close, they could die from strangulation, a crushed windpipe, broken neck, or a fractured skull.
(That's what prompted the poly rollers and mandating the master window locking switches and the individual "kid safety" switches on door edges that can't be reached when the doors are closed.)

BTW, once the first window's motor bushings go bad the other window's motor bushings are ticking time bombs.)

For those who DON'T have kids and/or DON'T intend to sell their vehicles there are also inexpensive solid ones available as replacements-those don't self-destruct. But they don't deteriorate from age.

 

[johnnyreb]

What johnnyreb is referring to are the polyurethane "rollers" that are in the gear case. They are 3 in number and about 1/2" diameter x 3/8" tall.

The original-type rollers are made of that material so they will shred if the window glass encounters too much resistance when closing a window.
ITS FOR A VERY GOOD SAFETY REASON.
If they DON'T shred, when a kid has his head through the open window and triggers the window switch to close, they could die from strangulation, a crushed windpipe, broken neck, or a fractured skull.
(That's what prompted the poly rollers and mandating the master window locking switches and the individual "kid safety" switches on door edges that can't be reached when the doors are closed.)

BTW, once the first window's motor bushings go bad the other window's motor bushings are ticking time bombs.)

For those who DON'T have kids and/or DON'T intend to sell their vehicles there are also inexpensive solid ones available as replacements-those don't self-destruct. But they don't deteriorate from age.

Well I am about to find out before long. What is wrong with mine. I don,t know if its rollers or the track it runs on. I can lift the sides up and the window will go up--I say its the track,but I,ll check both of them out. Thanks for the information GoodO1boydws----I did not know that.

 

[goodO1boydws]

If my experience is any guide, and you can still get he window to come up while you're pulling on it and pressing the "UP" button, its likely the bushings are only partially crumbled. IF SO, the best bet is to keep it up as far as you can until you take the door panel off. If you don't get it up most of the way now you may not be able to get it to stay up again.
And if its already slipping back down some when you let go of the glass, get out the Duck tape to HOLD it up. Cuz this is when it usually starts to rain.....a lot.

 

[johnnyreb]

Well mine stays up,but as you said. The other day I was gonna put some stuff in the back and a rain was coming. I had it down about half way and it started raining and WOULDN,T DO ANYTHING---LIKE NO POWER AT ALL. I started lifting it up and the switch started working again. I got it up all the way with the switch and it stayed up. I have replaced about everything on this bronco--except the motor in the tailgate. Guess I,ll end up replacing it too. .

 

[goodO1boydws]

Something I forgot to mention.
Next time, before you try to use the switch for that window, GENTLY lift up on the glass and see how much it will move. If there's more than about 1/8-1/4" of freeplay/vertical movement that play is almost certainly from the rollers being degraded. There's another other possibility though. (It usually begins AFTER the rollers start to degrade-from small pieces of them that get wedged where they shouldn't be.)

There is a NYLON gear that the poly rollers sit in, which also holds the tri-lobed metal gear. The motor turns that NYLON gear, by means of a METAL open tooth worm gear, and sometimes a few of that NYLON gear's teeth get worn off in one section. When/if that happens, the motor spins (and you can hear that), and the metal gear turns but the NYLON gear with worn off teeth doesn't, so the window glass doesn't move. Often this happens when chunks of the rollers get between the PLASTIC gear's and the worm gear's teeth.

If there are only TINY pieces of the poly rollers between the plastic and metal gear teeth, its possible that they may not be big enough to STOP the gear rotation, but only make it harder for the gears to turn during part of their rotation,. If THAT happens the window would tend to move at a slower speed ONLY when the teeth are in that position, and then speed up again.

So if your window glass is moving ok for some inches but then needs your help to lift (or lower it) that might be what's happening-you're just helping it to get past the missing/damaged/blocked teeth.

This is what the parts that are likely to be damaged look like, and this particular kit covers a lot of years but it doesn't cover every Ford window motor. Note the very shallow teeth on the outer edge of the big nylon gear-it doesn't take much to block those. (the kits and the rollers by themselves are available through lots of places like AutoZone, Advance, etc.)

1980-4/1992 Ford Bronco and F-Series Truck Window Motor Gear Repair Kit-Broncograveyard.com

Repair kit for replacing the plastic gear in lift motor.br New Gearbr gear dia. 2 1/8 made before 5/1/1992br D0AZ 62234A24-B FORD MOTOR CObr •Direct replacement for a proper fit every time •New gears can help restore smooth window operation on older vehiclesbr •Replace the part, not the...

shop.broncograveyard.com

 

[my87fordbronco*]

84 Bronco....Rear window goes up and down painfully slow and stops partway in both directions. I can always pull/push it up/down the rest of they way by turning the t/g key.

It has a new motor, gears/tracks have been cleaned, lubed and it has new little glide thingys in the tracks too. The dash switch has been cleaned and the grounds behind the dash were all cleaned and renewed too.

Heres my conundrum:

- If I give it juice straight from a battery to the window motor on the window side of everything it shoots up and down great.

- If I hook wires up and give it juice so it works through t/g key ONLY the window will go up pretty well, but down is super slow and gets stuck about halfway.

- If I hook wires up and give it juice so it works the the dash switch ONLY the window goes up halfway and gets stuck, and goes down painfully slow.

I tested each scenario and get a full 12v when the switches are flipped to wherever power needs to go, and just to make double sure I even ran a dedicated 12v wire to the connectors and tried that too.

Since I was getting 12v everywhere, I thought maybe it was poor grounds. So, I also threaded the ground ***** hole in the drivers tail light area for a dedicated ground close by. One switch at a time nothing changed no matter the power/ground source combination.

Im trying to keep it as stock as possible and really dont want to admit that maybe after 40 years maybe the switches are just getting worn. Anyone have any suggestions I may have missed or overlooked aside from the switches themselves?

I had that same issue with my 87 Bronco. I found out the wires that go into the tailgate from the body at the hinge point had broken inside the cord . Replaced the electrical cord to the tailgate and it powers up and down great now. The wires inside the power cord get broke from being bent every time the tailgate opens and closes.