c/elevator-mechanics

Blew a motor controller on a 1984 Dover, learned a hard lesson

Last week I had a service call in a 12-story building in downtown Cleveland. The car was running rough, and I swapped out the limit switch without checking the brake release first. That mistake cooked the motor controller board, cost the building $1,800 for a reman unit and me a full Saturday. Anyone else ever fry a board by skipping the basics? How do you keep yourself from rushing on simple callbacks?

1 comments

the_emery•18d ago

TIL elevator counterweights are actually heavier than the car when empty

Was reading the old Otis maintenance manual from a 1972 install in downtown St. Louis last week. Turns out the counterweight is sized to the car plus 40-50% of rated load, so it's always heavier than an empty cab. That explains why a full car feels different on the way up versus down, and why the brake has to hold so much more when nobody's onboard. Anyone else ever calculate the exact ratio on a modern traction setup and get surprised?

1 comments

ryan_sanchez•18d ago

Replaced my old brake pads and the math finally makes sense

I put $420 into a full brake shoe set for an Otis unit in a 12-story building near downtown Tacoma. The old ones were wearing uneven and I kept getting nuisance fault codes. After the swap, the car runs smooth and I haven't seen a single slowdown in three weeks. Anyone else keep records of brake wear patterns to predict the next call?

1 comments

williamt44•20d ago

Hit 500 rescues logged in my service book today

I started keeping a tally of every rescue I did in the field back in 2021, mostly out of curiosity. Today I hit 500 and it caught me off guard, that number feels way bigger than I expected. It made me realize how many times I've been the one to get someone out of a stuck car, usually on a Friday afternoon. The 500th one was a routine jammed door sensor at a condo in Tacoma, nothing fancy. Anyone else keep a running count of their rescues, or am I just a numbers nerd?

1 comments

the_gray•21d ago

Hydraulic leveling valves vs. roped hydro, why I switched back

I spent two years on roped hydraulic systems for low rise work. The smooth ride is nice but the maintenance headaches are real. Last month I had a roped unit drop 4 inches in a 10 story building because the packing gland wore uneven. Swapped it for a standard hydraulic leveling valve setup and it's been dead level for 3 weeks. The valve cost $220 and took 2 hours to install versus the roped kit at $900 plus a full day. Maybe I got a bad batch, but has anyone else seen better reliability out of roped hydro long term?

1 comments

torres.elizabeth•21d ago

Spent $1,200 on a remote diagnostic kit, think it was a mistake

I bought one of those fancy telemetry setups from a vendor at the Atlanta trade show last March. It kept flagging false faults on the door operator, so I drove out to a site in Marietta that was 60 miles away. The old-school method, just watching the relay sequence with a multimeter, nailed it in 20 minutes. Anyone else find these smart gadgets cause more callbacks than they prevent?

1 comments

the_jessica•21d ago

Leveling off at every floor? Two schools of thought and I keep flip flopping

So I've been doing this for about 8 years now, mostly in older buildings around Pittsburgh. I always leveled off at every single floor, even on express runs. Thought that was just the correct way. Then last month I rode with a senior mechanic from a bigger outfit and he said he only levels at stops where passengers are actually getting on or off. He said the extra stops wear out the brake coils faster and he's seen 3 times the failures on cars that level constantly. I mean, I get that, but my way does give a smoother ride and catches door zone issues sooner. The dude had 25 years on me though. Did I have it backwards this whole time? What do you guys do on high rise traffic patterns? Has anyone else had that moment where a veteran makes you question your whole routine?

1 comments

brookef73•23d ago

That old timer who said never trust a car without a test ride

Back in 2011, a guy named Delbert at the union hall in Pittsburgh told me to always run a car empty with the safeties engaged before trusting any brake work. I thought he was just being paranoid, but after a job at the Westin where the brake release stuck and the car dropped two floors, I saw exactly what he meant. That lesson has saved me at least four times since, especially on older Otis units. Anyone else have a mentor whose warnings you blew off until they bit you on site?

0 comments

hall.emma•23d ago

Finally fixed a door dwell issue that stumped me for 2 days

Been chasing an intermittent door reopen on a 1999 Dover at a condo in Cleveland. Turns out the limit switch cam was worn just enough to skip every 15th cycle or so. Replaced the cam and it ran 200 cycles straight on my meter. I see young guys swapping whole controllers for this same symptom. Anyone else ever find a simple wear part hiding behind a ghost fault?

1 comments

averym82•24d ago

Rope lube on old traction sheaves, any luck?

Tried a new dry film lube on a 1987 traction setup in a St. Louis office tower last month and the car started slipping on the drive test, had to wipe it all down before the inspector came. I thought the graphite stuff would help the grooved sheave grip but it just made things worse. Anybody else run into this or is there a trick to prepping the rope before you apply it?

1 comments

thomas.piper•24d ago

Old Otis relay swap changed my whole approach to door locks

Pulled a crusty door lock relay out of a 1982 Otis in a downtown St. Louis building last week, put in a new one, and the doors finally stopped dropping mid-cycle. The before and after was night and day, it cycled 300 times smooth after. Anyone else see big fixes come from just swapping out those old magnetic relays instead of chasing wiring gremlins?

1 comments

jade226•24d ago

Tried tapping the brake drum with a hammer to line up an old Otis, now the governor has a stutter

Last Tuesday in a 12-story building near the Port of Oakland I gave that tired brake drum a friendly tap and the next run sounded like a snare drum solo, so has anyone else had a fix go sideways that turned into a two-day call?

1 comments

lindareed•25d ago

Found out elevator doors only need 11 inches of overhead clearance, blew my mind

Was looking at an old Otis manual from 1987 that a buddy left in the shop truck. It had a diagram showing the door operator and the counterweight setup. Turns out most hydraulic elevators can run with just 11 inches of headroom above the door track. I always figured you needed at least 18 or 20 inches for the linkage to swing. Checked it against a job we did last week in a 1960s building in Philly, and sure enough, the clearance was 11.5 inches. Anyone else ever misjudge clearance on an older unit and have to rework the rail brackets?

1 comments

davis.ivan•26d ago

Dropped $220 on a backup rope brake for the inspection cart, best money I've spent in ages

After that near miss in the Johnston building last spring where the cart slipped two floors, I finally bought the auto-lock unit and it caught a cable snap during a routine test run yesterday. Anyone else run these on older cars, or do you still trust the manual catch setup?

1 comments

kai807•26d ago

I finally checked an old elevator's oil logs, found a surprise from 1978

We replaced a 40-year-old hydraulic unit in a building off 5th and Main last week, and the maintenance book tucked behind the controller had entries from the original installer. Turns out that elevator ran on the same mineral oil for 31 years straight, and the viscosity readings were still within spec when we drained it. Anyone else ever find something wild in an old machine room logbook?

1 comments

davis.mia•28d ago

That retirement-age tech told me to quit fighting the limit switch, he was right

He said 'stop adjusting it every call, just replace the roller and leave it alone' back in March at the old Hilton on 5th, and after three return trips on the same car, I finally listened and it's been running smooth for 8 weeks straight now, has anyone else learned the hard way that the old guys skip the tweaking on purpose?

1 comments

mary_wells•28d ago

Two years of riding the door brake finally clicked for me

I used to always set the door brake to full stop on every car, figured it was safer for inspections. Then last month I was doing a mod in a 12-story office tower in Denver and the landing calls kept timing out. An older tech I was shadowing pointed out my brake was dragging the door operator motor, causing the relays to overheat and slow the cycle. He showed me his setup with just enough brake to hold the door, and the difference in call response was night and day. I still use full lock for service mode, but for normal ops I match it to the door weight now. Anyone else run into invisible door brake issues on newer controllers?

2 comments

shane_nguyen•1mo ago

Changed my mind about relay logic after talking to a building engineer at a 1970s high-rise

I used to think programmable controllers made relay logic completely obsolete. Then I was fixing a slow elevator in a downtown Seattle building last month and the head engineer walked me through the original relay bank. He showed me how a single stuck relay gave me a fault code that would have taken hours to trace on a newer board. He explained that relays fail in predictable ways and a good electrician can read the logic with a multimeter. So now I keep a spare set of relay schematics for older jobs instead of always pushing for full modernization.

2 comments

mason.mark•1mo ago

Found a trick for leveling elevator doors without pulling the whole track

Been fighting a set of doors on an Otis unit in a 12-story building downtown for weeks. Kept getting drift on the bottom guide shoe until a coworker told me to try using a small feeler gauge to shim the roller bracket gap instead of loosening the whole track. Worked on the first try and saved me at least 45 minutes of readjusting. Any of you guys use feeler gauges for door alignment or is there a better method?

2 comments

alicea26•1mo ago

Old timer on a service call taught me more about leveling than my whole apprenticeship

I was swapping a controller board in a 1990s Otis at a mall in Denver last month. This guy maybe 70 years old just watched me for a minute, then asked if I knew why the car was stopping 3/8 off every floor. He walked me through checking the selector tape tension without even pulling out a tool, just by the sound of the tape whirring. Has anyone else had a random encounter with a retired mechanic that totally changed how they troubleshoot?

2 comments

ray_carr•1mo ago

Just watched a guy try to fix a stuck door with a crowbar in a 20-story building

Last Tuesday I was working on a 15 year old Otis in a downtown Philadelphia office tower, and this new guy from another company shows up to help. Before I could say anything, he wedges a crowbar into the door gap to force it open... bent the metal track so bad the car wouldn't move for 2 hours. Has anyone else run into DIY types who think elevator parts are like house doors?

2 comments

sarah_hart•1mo ago

Spent 9 hours troubleshooting an intermittent leveling issue on a 1994 Dover in downtown Nashville

Turned out to be a corroded wire inside the selector tape that only lost connection when the car passed the 10th floor. Has anyone else found something dumb like that on an old relay board that took way longer than it should have?

2 comments

elizabethf85•1mo ago

Old timer showed me something about ropes I never forgot

Back in 2008 I was working a 12 floor job in downtown Detroit and this older mechanic named Roy came up to fix a busted compensator chain. He pointed at my splice and said "you're twisting the strands wrong, watch me" then redid it in 3 minutes flat. Does anyone else have a memory of someone who just looked at your work and fixed it without saying much?

1 comments

lucas_grant83•1mo ago

Overheard an old timer say something about governor tension today

Was on a service call at a 12-story building in downtown Austin and this retired mechanic told me loose governors cause more nuisance shutdowns than bad switches. Anyone else find that true or just old school talk?

2 comments

harris.uma•1mo ago

Wasted $300 on a 'universal' rail oil that wrecked my bearings

I bought a 5 gallon bucket of this no-name rail oil from an online surplus place because it was half the price of the name brand stuff. After about two weeks of using it on a busy office tower in downtown Denver, I started hearing this grinding noise from the guide shoes. Opened up the rails and found this thick, sticky gunk that had gummed up all the bearings, had to replace four sets. Has anyone else tried cheaper oils and ended up paying way more in repairs?

2 comments