Chamberlain 248739 Belt Drive Parts

Chamberlain 248739 Replacement Parts

The 248739 is a square rail belt drive opener. Its belt, rail, trolley and U bracket are square rail specific and will not interchange with the T-rail parts used on most belt drives. Everything for it is on this page — the reference numbers below match the diagram.

Ordering a belt? The 248739 takes the 041A5250 square rail belt, sized to your door height. Check that your rail is square in section before ordering — the square rail and T rail belts are not interchangeable.

1. Garage Door Opener Repair Parts

Chamberlain 248739 square rail belt drive opener parts diagram

First part of number below corresponds to diagram number above:

Ref	Part Number	Description
01	041A4371	Belt cap retainer
02	041A4885-5	Gear and sprocket assembly
03	041B4245-1	Line cord, 6 ft
04	041A5484-10	End panel with all labels
05	041C0279	Light socket
06	K108D0079M	Light lens
07	K030B0532-1	Capacitor
08	K012A0373	Capacitor bracket
09	041A3150	Terminal block with screws
10	041C4842	Motor
11	41A5525-4	Cover — no longer available
12	041A2818	Limit switch drive and retainer
13	041D3452	Limit switch assembly
14	041A2822-1	Interrupter cup
16	041AB050-2M	Receiver logic board assembly
17	041C5499	High voltage wire harness
17a	041C5500	Low voltage wire harness
18	041D0180-1	End panel
—	041A2825	Opener assembly hardware kit — not shown on diagram

Cover no longer available. The ref 11 cover (41A5525-4) is discontinued with no replacement. Every other part on this diagram is available. The 041AB050-2M is the current receiver logic board — read the number printed on the board you are removing before ordering, and call (866) 965-5599 if it is not this one.

2. Rail Assembly Parts

First part of number below corresponds to diagram number above:

Ref	Part Number	Description
01	004A1008	Master link kit
02	041C5141-2	Complete trolley assembly, square rail
03	041A5665-2	Square rail
04	041B4103	Belt tensioner
05	K144C0054M	Idler pulley, wide, for belt drive
06	041A5250	Full belt assembly — 7 ft door
07	041D0598-1	U bracket, square rail
—	183A163	Wear pads — not shown on diagram
—	041A7920-2	Installation hardware bag — not shown on diagram

A belt rarely fails on its own. Check the idler pulley, trolley, tensioner and wear pads while the rail is apart — worn pads let the trolley rock in the rail and will chew through a new belt in months.

3. Installation Parts

First part of number below corresponds to diagram number above:

Ref	Part Number	Description
01	041C0494-2	Multi-function door control panel — replaces 041C0494-1
03	10A20	3V CR2032 remote battery
04	K029B0137	Remote control visor clip
05	041A2828	Manual release rope and handle assembly
06	041B4494-1	2 conductor bell wire, 26 ft
07	041A5047-1	Door bracket, black — belt drive units
08	041A5047-3	Header bracket for square rail
09	041-0136	Safety sensor eye kit — replaces 41A5034
10	4178B0034B	Straight door arm section
11	K012B0776	Hanging bracket
12	041B0035B	Curved door arm
12–13	041-0155-000	Safety sensor brackets — replaces 41A5266-1
—	041-0365-000	Sensor eyes and brackets — the complete set
—	373LM	3 button remote control
—	893MAX	3 button visor remote — universal replacement

This is a pre-1998 opener. Its wall control is the 041C0494-2, which replaces the discontinued 041C0494-1. The modern 889LM and MyQ panels will not work on it. The ref 12 and 13 sensor brackets (41A5266-1) are also discontinued — the 041-0155-000 above replaces them.

If you need eyes and brackets, the 041-0365-000 is the complete set and works out cheaper than buying them separately. The 893MAX is the universal replacement for older Chamberlain, LiftMaster and Craftsman remotes — browse all Chamberlain remote controls.