Step motor keeps running.

[hogman69]

I have a question. 05 Monaco monarch 2 step. The steps go in and out perfectly. what I am noticing when steps retract, the motor keeps running for about 5 more seconds. Is that normal? I would think that once step is retracted completely the motor should stop.

[FIRE UP]

Originally Posted by hogman69

I have a question. 05 Monaco monarch 2 step. The steps go in and out perfectly. what I am noticing when steps retract, the motor keeps running for about 5 more seconds. Is that normal? I would think that once step is retracted completely the motor should stop.

Hogman69,
Well, let me ask you something here. When your steps are all the way retracted, and the motor keeps running, do you hear any sort of odd noises, sort of "grinding", anything out of the ordinary? The reason I ask is, mine did the same thing back about a year ago and what it turned out to be was the main DRIVEN gear in that Kwikee step gear box, had a broken tooth that located in such a manor that, that's where the drive gear would end up, each and every time, at the end of the travel.

The rest of the teeth, on both the drive and driven gears were in perfect shape. In fact, since there was only one broken tooth, and the fact that due to the way the system is designed, the other side of the driven gear IS NEVER USED! So, I simply reversed the driven gear to use the other half.

All was well except for the fact that, instead of the motor still trying to run at the end of retraction, it kept trying to run at the end of EXTENSION

So, after messing around with it for a day or so, I said the heck with it and, ordered up a brand new gear box from Amazon. I got a waaaaaaaay better deal than ordering it up from Kwikee and any other parts supplier.

Now, is this your problem, who knows? But, it's maybe something to look into. Those motors and drive gear systems are gear to gear so, there is no clutches or other mechanisms that can have or, are intended to "slip" if things get in a bind.
Scott

[dpinvidic]

What kind of steps do you have (Kwikee steps)?

Mine are Kwikee, and the motor stops when they are fully retracted or extended.

"Normally" the motor is a direct drive to the steps, so if the steps are actually moving, then the motor will be running.
Sounds like what the Fireup explained, some kind of slipping going on. Not normal from my experience.

question, I would expect that the motor also runs the same amount of time before the steps stat moving on extension if there is slipping.

Regards,

Dan

[ga traveler]

Inside the motor housing is a set of three "marbles". They are a plastic materiel. They are to cushions the motor. When they get old, they break down. This can cause the motor to keep running until they get into a position to stop the motor. You can buy just the marbles instead of the whole motor.

[Sweetbriar]

Originally Posted by ga traveler

Inside the motor housing is a set of three "marbles",,,

Magic marbles? Never heard of such. I have seen magic smoke come out of stuff that never worked again.

The controller will shut off power to the motor when it senses high motor current demand when the stairs are at the end stops, if the stairs jam against something like a curb, if the stairs need lubrication and are difficult to move or if the chassis ground is dirty causing a high resistance load.

What the OP has is a broken tooth on the main gear just as FiredUp discribed. If happens plus the gear isn't case hardened steel and probably ment to be the weak link in the system. You can flip the gear over and reverse the power leads to the motor to change rotation direction. Other option would to replace the gear box. Had the same problem on my coach but at the extended position. One broken gear tooth and the motor would keep running until I pull the stairs out past the broken tooth. Found a gear box at PPL but that was back when Amazon didn't have much in the way of RV stuff.

Watch your fingers working on the steps. Get them in a pinch point when the steps are moving and,,,. Painful just typing about it.

[hogman69]

Gentlemen, Thank you for all your input. This gives me a lot of food for thought and I will go check out all your suggestions. Stay tuned.

[TeJay]

Our coach is going on 2 years old so I don't think things are worn out just yet. Actually the steps have been replaced once under warranty.

I just had the pleasure of fixing our steps. By the way Kwikee Steps make most RV steps I believe. At least in my search I didn't see many other manufacturers. I also called the factory and got some very good advice from their techs.

Even if you don't work on your own RV so you have a better idea of what is happening crawl under the coach with a good flashlight and have somebody actuate the steps so you can watch and kind of see what is really happening. Watch out so you don't get hit with the steps going in or out. And for sure (as already noted) keep your fingers away from all levers, moving arms, pinch points etc.

We had a broken wire behind the magnetic switch which would actuate (when ever it wanted to) while driving down the road. My DW had to stand on the inside coach exit step until I could pull over and unplug the steps to keep them from moving while we were moving. With a tip from the techs I found the broken wire and fixed it.

TeJay

[matcoman]

Try this:
Amazon.com: Dorman 74409 Window Regulator Gear for Select Ford/Mazda Models: Automotive to replace the nylon gears.

Or, this is an inexpensive complete motor replacement:
ACI Window Lift Motor 83694: Advance Auto Parts If you go this route, you will have to cut the pigtail off of the old motor and splice it (hopefully with solder and shrink-wrap) to the new motor. Other than the pigtail plug, this motor is an exact replacement to the original step motor.

[hogman69]

UPDATE, Got a good look at the gear. As you guys suggested, the last half dozen gears are badly worn. They look like they were filed to a sharp point. So I have a new one on the way. $40.00 delivered from E-Trailer.com

[ga traveler]

Originally Posted by Sweetbriar

Magic marbles? Never heard of such. I have seen magic smoke come out of stuff that never worked again.

The controller will shut off power to the motor when it senses high motor current demand when the stairs are at the end stops, if the stairs jam against something like a curb, if the stairs need lubrication and are difficult to move or if the chassis ground is dirty causing a high resistance load.

What the OP has is a broken tooth on the main gear just as FiredUp discribed. If happens plus the gear isn't case hardened steel and probably ment to be the weak link in the system. You can flip the gear over and reverse the power leads to the motor to change rotation direction. Other option would to replace the gear box. Had the same problem on my coach but at the extended position. One broken gear tooth and the motor would keep running until I pull the stairs out past the broken tooth. Found a gear box at PPL but that was back when Amazon didn't have much in the way of RV stuff.

Watch your fingers working on the steps. Get them in a pinch point when the steps are moving and,,,. Painful just typing about it.

Why the sarcastic remark about marbles. As a service manager I worked on probably a hundred steps. I opened over a dozen motors. I replaced a half dozen or so marbles. How many steps have you worked on? How many motors have you opened up? The reason I don't believe he has a broken tooth is answered by you. When a tooth is broken the steps come to that point where the tooth is broken and then run until you push the step and cause the next tooth to engage. He says the steps come in all the way and run 5 seconds after closing all the way. If the marbles have broken, The motor gears would keep tumbling the marbles around until they meshed up enough to catch and shut the motor down. My answer is not the only one but it is a big probability.

[Sweetbriar]

Because a modern coach electrical step uses a current monitoring controller to stop the motor. Also the step motor is best to just replace with a form, fit and function power window motor you can pick at the corner NAPA. Usually the gear box fails on extension if weight is placed on the steps before full extension but it can fail at full retraction. The small motor doesn't have a lot of torque but it has speed. The gear box will convert high speed low torque rotation into low speed high torque. Once fully extended or retracted the gear train will lock the steps in place. Lose one tooth and excess stain is placed on teeth either side until more teeth brake. Break enough teeth the steps stop moving and the motor continues to run until it either grabs intact teeth or a bit of help occurs. Some controllers also have a timer function to shut down the motor after a preset activation period of a few seconds so it doesn't drain the battery. Also the OP responded that the bull gear had damaged teeth. Very common failure point which is why you can get gear box parts from Amazon.

So far I've only worked on one set of steps but during the course of many years as a sailor I have worked on and repaired motors from 1/2 to 10 HP, DC, single phase and multi phase AC motors. Well actually never repair a motor. We usually sent them out for a stator or rotor rewinding once a meager check showed a failure or when a failed brush damaged the commutator. The controllers, gear boxes or shaft couplers were usually the failure. Did replace a couple of shaft bearings which was pretty simple once measurements were taken and cross referenced. Lots of time with mechanical and digital speed governors and controllers, low and high voltage slip rings, tachometer feed back loops, gyro rate integrating circuits and such. Pretty cool to get a digital 6 phase motor controller and gyro circuit dialed in just right and watch a 1500 pound radar antenna snap around 180 degrees in less than 1/2 a second to grab a high speed target and never let go.

I can keep going into fire control and surveillance radar systems (cooked a bag of popcorn with the radar in 5 seconds a few times), digital and analog radar display systems, closed loop liquid cooling systems, composite fiberglass matrix repairs but that would be moving away from motors and related circuits. Go Navy Beat Army, oh right they did, again.

[ga traveler]

Shouldn't that be megger check and not meager check. lol. ( I was in the electronic dept at Delta Air Lines)

[Sweetbriar]

Originally Posted by ga traveler

Shouldn't that be megger check and not meager check. lol. ( I was in the electronic dept at Delta Air Lines)

You are correct. Great for charging caps then tossing them to unsuspecting new techs to catch.

[FIRE UP]

To the OP,
As you've found out, you've got some bad TEETH. Well, here's what mine looked like when I was having somewhat the same problem as you.
Scott

P.S. If you look closely at the drive gear, (the smaller one) you'll see one of broken teeth from the larger one, lodged in between two teeth of the smaller one.
Scott