Tip & How-To about liftmaster Chamberlain Garage Door Opener Transmitter 300MC

How to safety check your garage door opener

Place a 2x4 (or other object that is solid and about 2" thick)flat on the ground in the middle of the door. Activate the opener and lower the door until it makes contact with the 2x4. It should hit the 2x4 and then reverse in the upward direction. It can put pressure on the 2x4 just not stay there. If it reverses then it has passed. If it stays down then find the down force adjustment on the opener and turn it down. This adjustment can be found in your manual and will differ in location from brand to brand of garage door opener. Check the belt/chain for slack when it is running(there is no need to check this on a worm drive opener). If there is more than 3/4" slack then tighten it up with the tension adjuster on the trolley. Check the force adjustments per the manual as well. Do not pay attention to this slack when the door is shut as the trolley arm presses on the opener arm to gain the best seal at the bottom of the door. If you have a screw drive you can lubricate the screw with liquid graphite. All other types need none unless you want to lubricate the nylon gear inside the unit with rail grease, but be careful here and unplug the unit first. If your garage door opener has safety eyes start the door down and then cross the beam. The opener should reverse upward. If it does it passes, if not then call a reputable repair firm. Thanks BB

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how to align driver side door for a 1999 gmc yukon denali


Sagging door? Place a 2x4 between the door and the door post at the lower hinge and close the door a bit on it,this will raise the door.Try a little at a time until the door closes good.

Jul 21, 2017 | GMC Cars & Trucks

1 Answer

have a famous trails md 7030 how do you fine tu\ne it? mode ?" ground?


http://www.famoustrails.com/manuals/MD7030%20Manual.pdf

  • Place the pad flat on the ground and then turn the tuner kuntil it centers in the middle ..push the reset button several times until it is in the middle on the dial..then place a ring or something that is the only thing ..do it on a table or etc where u wont have any interference ..such as pipes or metal in the floor. practice going from one object to another until you can tell the difference in how the tone changes..the higher the pitch the more chance of it being a solid hit.. use the discrim to adjust for such inferernce from such things as wiring or pipes..etc..
  • good luck
  • chadman

Mar 23, 2013 | Famous Trails Discriminator Ii Metal...

3 Answers

Every time I open the door it hits the fender And makes a popping sound !


the hinge could have been bent in an accident but you can try shims where it bolts to the frame to give you more leeway.

Jan 22, 2013 | Vehicle Parts & Accessories

1 Answer

I have a Famos trails metal detector model MD 7030. I need a owners/users manual as I have purchased my unit 2nd hand. I have not ben able to download a manual as my program does not like the download handeler. The famous trails sight has all manuals downloadable except MD 7030. I dont know how to use the discriminators and I need something (info) so that I can use it to its best purpose. Thank you


Http://www.famoustrails.com/manuals/MD7030%20Manual.pdf

  • Place the pad flat on the ground and then turn the tuner kuntil it centers in the middle ..push the reset button several times until it is in the middle on the dial..then place a ring or something that is the only thing ..do it on a table or etc where u wont have any interference ..such as pipes or metal in the floor. practice going from one object to another until you can tell the difference in how the tone changes..the higher the pitch the more chance of it being a solid hit.. use the discrim to adjust for such cross pickups from such things as wiring or pipes..etc..
  • good luck
  • chadman
chadmanquake_4.jpg

Feb 13, 2011 | Famous Trails Discriminator Ii Metal...

1 Answer

how to fix a sagging car door neon


Here's an old body and fender repairman's trick:
Use a 4-foot length of 2x4 lumber to carefully pry up on the bottom of the door.
The best way to do this is to place one end of the 2x4 in the door opening while firmly lifting the other end to adjust the door upward as needed.
BE CAREFUL NOT TO BEND THE OUTER SKIN OF THE DOOR.
Another 2x4 technique is to set one end of the wood in the door opening, the other end on the ground.
Slide the door in and push it up the 2x4 "ramp" to adjust.
Check your progress often because this leverage will move it fairly easliy and you don't want to go too far.

Dec 03, 2009 | 1997 Dodge Neon

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