The LU-4 Series Braden Winch is used on the Dodge M-37 Trucks. The Winch on the 'M-37' suffered a seized winch clutch. The Handle could not be moved. Unlike the Braden MU-2 Series used on the Power Wagons where the winch clutch is exposed, on the LU-4 series it’s enclosed in the right housing. To determine what was seized, exploratory surgery would be required. Since the right housing would have to be totally removed, I decided to totally tear down the winch and replace any worn parts. Without question all seals and gaskets would be replaced. Other parts would be replaced on a 'as need' basis.
The pictures of the disassembly are in order and as I found it. Someone had not assembled the winch correctly. See if you can spot the mistake. If you get to picture 18, you have missed the error. As a result of the assembly error, someone had to make a modification to complete assembly.
The Braden Series LU-4 and the Series MU-2 share the same design concept in the worm drive unit and bronze worm gear and main winch drum shaft. The cable drum and right hand declutching of the winch are different. As you tear down a LU-4, its easy to see that a MU-2 is a much more robust winch. I was easily able to lift a complete LU-4 with no cable from the floor to the workbench. I can’t do that with a MU-2.
Once everything was opened up, it was easy to see that over the years water had run down the winch clutch shifter shaft and seized it in place. A complete inspection showed the bearing cones and cups on the worm drive to be in excellent condition. All bronze bushings showed no wear, hardly an indication of shafts rotating. Clearly this winch had been used very little if at all, or it was rebuilt.
There is nothing difficult about rebuilding a LU-4; anyone with normal tools should have no problems. I have tried to take photos of each step, along with a description of the process being done. After total strip down, all parts were washed in a parts washer to get rid of the crud and grease that destroys the action of a blast cabinet. Once cleaned up, all parts were blasted with glass beads, with absolute protection given to gasket surfaces, bushings and bearing cups. Then a very careful final cleaning in virgin solvent and everything is ready for paint. All parts are primed with PPG MP-170 Epoxy Primer. Then shot with PPG MOA Hardened Chassis Black. The resulting paint will have a Black Satin finish. Then the final assembly.
Date(s): Braden LU-4 Winch Rebuild. Album by Power Wagon. 1 - 56 of 56 Total. 17950 Visits.
1 LU-4 Winch Break down
2 LU-4 intact on my M-37
3 LU-4 ready to open up, drain lubricant on both sides and remove the top plate that ties both sides together. Also remove large nut on lower tie rod. Remove mounting bracket from housing.
4 With Winch sitting on Bench, supported, carefully pull the right side case off the winch. Right side mount removed.
5 You can now see the clutch dog, shift fork and shift rod
6 Clutch dog and spacer, Spacer is first next to the bushing, then clutch dog sits in the shift fork
7 Remove both Keys on the main winch shaft and then remove the spacer on the main shaft
8 Winch drum will now slide off
9 End view from the left side, remove the mount bracket
10 Remove end cap/bushing retainer
11 Remove (4) 3/8" bolts that hold safety brake housing on bearing retainer, and then remove bearing retainer
12 Remove bearing retainer on the drive shaft side (4) 3/8" bolts
13 The shaft with the bearings and worm can now be worked out the front or rear of the gear case. Be CAREFUL, the worm edges, and Bronze gear edges are razor sharp from a honing action between the two.
14 Looking in the gear box at the main shaft and bronze gear. Slide out the main shaft with the bronze gear and remove. Be CAREFUL, the Bronze gear teeth are razor sharp from a homing action with the worm gear
16 Worm Gear/Main Shaft out
18 Gear housing is now stripped with the exception of the main shaft bushing. You need to determine if the bushing is worn. If so replace
19 Another view of the Main shaft bushing
20 Protect all gasket surfaces prior to media blasting. I use sticky back heavy plastic to protect gasket surfaces.
22 Main shaft bushing protected prior to media blasting. All my bushings were like new. Winch had very little time, or had been rebuilt.
23 The Oil Seals are pressed out of the bearing retainers
24 Seal pressed out
25 Right hand housing with winch clutch. Casting is upside down. Pop the dimple disk seal that is in line with the shift shaft.
26 Disk is removed, now remove lock ring on shift shaft end
27 Shaft with lock ring removed
28 The shift fork is retained on the shift shaft with a large set screw that runs through the shift shaft. This setscrew must be totally removed.
29 If luck is with you, the shift shaft can now be tapped from the bottom and will come out the top, while sliding off the shift fork. If it’s seized use all known methods to free the stuck shaft.
30 Shift shaft setting in place for reference.
31 Worm shaft with bearings and also main shaft with bronze gear. You will have to determine in bearings are serviceable or need replacement. If so, they will have to be pressed off, an new bearings pressed on. Determine if the Bronze Gear is ok or in need of replacement. You will need to press it off the shaft to replace.
32 All parts are now media blasted and then totally cleaned
33 The next 4 pictures are a trial fit of the main shaft and worm drive shaft
37 Make sure air vent is clean and not plugged
38 Chase the threads on all tapped holes on the entire winch
39 My shift shaft had terrible corrosion in the shift shaft tube. I used a reamer to just 'love' the tube. No reaming of aluminum was done, just corrosion removal.
40 The next 2 pictures are re assembly of the winch brake. Replace your oil soaked brake band or clean up the original if not oil soaked. Be sure to put the 3/8" x 1 long bolt in place before putting the brake band in place. Or you wont get it in later.
42 The Bearing retainers require gaskets on both ends. These gaskets are available in 1/32" and 1/64" . "These gaskets set worm shaft end play. The worm shaft must have 1/64" to 1/32" end play to allow for expansion due to heat during operation. Do not set shaft without end play. Play is adjusted by gasket shim." Dodge Manual
43 Lightly oil the inside of the main shaft bushing and slide the main shaft/bronze bushing in place, then insert the worm drive shaft. Be sure that the end drilled for the shear pin is facing aft and the keyed end facing forward.
45 Install bearing retainers with gaskets and tighten down and check end play and adjust as needed. When end play is correct, remove the bolts on the winch brake end of the shaft and then insert the key.
46 Now install the winch brake drum. BE SURE the square lock bolt is facing out.
47 Tighten the square lock bolt
48 Install winch safety brake housing and bolt down. Now you can see in the picture why it was important to insert the bolt under the adjusting screw prior to installing the brake lining.
49 I put a generous coating of never seize on the main shaft. Having inspected the bushings in the winch drum, replacing if needed, slide the winch drum on the main shaft. Then slide one spacer marked SS on the parts breakdown. Then insert the 2 keys in the main shaft. Now test slide the shift dog in place and check for free movement and then remove.
51 Slide the shift shaft down into the shift shaft tube and at the same time sliding it through the shift fork. Be sure the hole in the shift shaft is lined up with the hole in the shift fork and then screw in the set screw. The set screw must go all the way through the shift shaft to the other side. It will be flush with the shift fork when all is correct.
52 Put the snap ring on the bottom of the shift shaft. Put your favorite sealer in the edges of the hole and insert a 1.250" dimple disk. When all is in place, put a large flat punch on the dimple disk and dent it in. This forces the dimple disk to lock in the hole.
53 Install a new gasket and replace the left side main shaft-bushing retainer
54 For a pictorial example, this is how the shift dog will sit into the dogs in the drum and then the spacer sits on top of the shift dog.
55 Take some heavy grease and generously apply a thick coat to one side of the spacer and set it place in the right hand housing sitting directly over the bushing in the housing. This will stick the spacer to the housing end. Then place the shift dog into the shift fork. Be sure the shift lever is in the WINCH not engaged position. Now with the winch in a horizontal position, slide the end housing over the main shaft. You will have to turn the shift dog to line up with the keys on the main shaft. When everything is lined up, the end housing will slide right on. Install the top plate that ties both sides of the winch together. This plate is critical in dimension as it holds the winch together and true. Otherwise the winch housing can bind the main shaft if just the bottom tie bold is used to secure the two sides of the winch.
There is no picture. I could not hold the housing in place, snap a picture and maintain sanity. Refill all fluid levels.
56 LU-4 is back on frame rebuilt. Now adjust the safety brake. The following is a quote from TM 9-8030 M-37. Remove outer jam nut from the brake band end. Insert a long punch through the shear pin hole in the worm shaft. Oscillate the shaft with the punch and at the same time tighten the inner jam nut on the brake band end until a noticeable drag is felt when the worm shaft is rotated in one direction. Hold the inner jam nut and install the outer jam nut and tighten".
The top plate was missing on my winch and 2 pieces of angle were used to tie both sides together, with elongated holes. This was probably done due to the assembly problem and the original top plate would not line up. I plan to make a 3/16" diamond plate piece to tie both sides together and then have it Line-X covered. It will be a handy skid proof place to stand while working on the engine