Garage Door won't stay closed or opens too far - Limit & Force Adjustment Liftmaster

hey guys Adam here in this video I thought we'd answer a question I get every once in a while this is a from Thomas Julie says my door is working however when it comes up it travels too far so that the trolley crashes into this stopper bolt and gets jammed a few whacks with a hammer and the trolley releases how can I stop it from going too far what he's talking about there is on the lefty of the trolley and that travels closer to the opener till it hits the bolt and in that case it's gone too far so that's about the distance you want about four inches and you also want to make sure that your door is open all the way you don't want it coming down in case something hits it like your car or whatever so this door is opening to the correct height there's nothing wrong with this but let me show you what you need to adjust right here are the limit adjusters you can see this one is to control the amount that it goes down this one adjust amount it goes up so right here there's some others and these are get this right here behind the cover these are also two that will adjust the amount of force and that's a little bit different now I have to know that anytime you adjust any of these knobs it might affect the other so you might have to adjust several even if that's not what you planned on and at the end of all adjustments we're going to do a safety test with that 2x4 there so be sure to watch the entire video and make sure you perform this test so I'll show that at the end okay Thomas so the problem you have is this trolley rams into that bolt that's going too far up in the up position so we're going to adjust this to go back a bit and it goes about when you adjust these screws I think a turn equals about two inches roughly so I'm going to make mine go back even further just so you can see how it works here so I got a screwdriver and there's a little little dark there but you can see and put this in here and turn it back words like that and we'll see where this ends up I'll hit the button and there we go that's about an inch and a quarter inch and a half so that's all you need to do now I'll go over the other adjustments in case anybody else has problems like if the garage door is coming down and bouncing back up we'll cover all of that right now a couple things to point out when you're adjusting this you need to run the opener through a complete cycle after each adjustment that you make also if your opening and closing it a lot it can cause the motor to overheat and you'll have to wait about 15 minutes because it'll shut itself down so just hang out for a while let it cool off and then you can do it again if that happens to you so let's say that your door opens but not completely so maybe it opens about head high and stops well then you can adjust the travel limit so you turn the up limit clockwise remember one full turn is about two inches of travel and remember to keep the trolley about two or four inches from that protection bolt now if the door doesn't open at least five feet you need to adjust the up or open force and increasing it increases the force that's going to pull so if there's a problem with your track or some other problem that's causing it to have a lot of friction you need to solve that instead so I would suggest pulling the safety and trying a balance test opening and closing the door by hand let's say you try to close the door and it doesn't close completely and we're also assuming there's nothing blocking it you need to increase the down travel so turn the down limit screw counterclockwise again one turn equals about two inches now let's say your problem is you close the door it hits the ground and it bounces back and it starts to open again you need to decrease the down travel so that's the limit adjustment you turn it clockwise again one turn equals about two inches of distance that the door is going to travel so let's say you're closing your door and the door starts to open back up in the middle of the cycle if your opener lights are flashing on and off then you have a safety sensor issue so they're either a misaligned or maybe a wire came off something like that so now we're going to test the safety reversal system and this is a good idea to do anyway but especially if you've adjusted the knobs and this is good because people could be hurt or little children especially could be killed by a door that closes and doesn't bounce back open so what you're going to do you place a 2x4 on the ground let the door go down and if it hits it and bounces back up that's great if it hits it and stays down like this one we have to fix it so you increase the down limit by turning it one-quarter turn and you can test it again so it should hit the board and bounce back up well that's going to do it for this video hopefully it's been helpful to you and good luck fixing your opener if you want to help support this channel in helping me make more videos you can click the support button it's on the about page and I'd appreciate that also if you have any questions go ahead and leave them in the comments section and I will do my best to answer you guys have a great day take care

Channel: AdamDIY

Views: 1,242,589

Keywords: Home repair, DIY, AdamDIY, how-to, garage door, Liftmaster, Chamberlain, Won't close, opens back up, test, safety, Limit, Force, adjustment, Open force, Close force, down limit, up limit, repair

Id: uSyI-zbpxEc

Length: 6min 1sec (361 seconds)

Published: Sat Apr 16 2016