LU-4 Winch-to-Bumper Bracket Bolts

Discuss fixes, upgrades and modifications to your M37

Moderators: Cal_Gary, T. Highway, Monkey Man, robi

Post Reply
Elwood
MSGT
MSGT
Posts: 937
Joined: Mon Oct 24, 2011 9:34 am
Location: Water Winter Wonderland

LU-4 Winch-to-Bumper Bracket Bolts

Post by Elwood »

I'm sourcing new grade 8 hardware to mount my rebuilt winch, and noticed that the ORD 9 SNL (1954 version) specifies 5/8-11 x 1" hex head cap screws (p/n 122724, group 2001.1) to attach the "L" shaped bumper brackets to the front faces of the clutch and gear housings of the winch. But the housings on my LU-4 winch will definitely not accept a 5/8-11 thread. More like a 9/16-12 thread. Is the parts catalog in error, or do I have an LU-4 winch intended for some other application, maybe an M-715?
“When a long train of abuses and usurpations, pursuing invariably the same Object evinces a design to reduce them under absolute Despotism, IT IS THEIR RIGHT, IT IS THEIR DUTY, TO THROW OFF SUCH GOVERNMENT...” -Declaration of Independence, 1776
NAM VET
1SG
1SG
Posts: 1118
Joined: Mon Aug 22, 2016 6:27 am

Re: LU-4 Winch-to-Bumper Bracket Bolts

Post by NAM VET »

I will check what I have on my bumper/winch in the am, and see what works for me.

NV
just me
1SG
1SG
Posts: 1195
Joined: Fri Nov 28, 2014 4:25 pm

Re: LU-4 Winch-to-Bumper Bracket Bolts

Post by just me »

My winch is 9/16". The bumper is ⅝".
"It may be ugly, but at least it is slow!"
Elwood
MSGT
MSGT
Posts: 937
Joined: Mon Oct 24, 2011 9:34 am
Location: Water Winter Wonderland

Re: LU-4 Winch-to-Bumper Bracket Bolts

Post by Elwood »

just me wrote:My winch is 9/16". The bumper is ⅝".
Fig 21-1 must be reversed then. It shows the bolts from the bracket into the winch housings as p/n 122724, which the itemized listing in group 2001.1 describes as "SCREW, cap, hex hd, S, cd or zn-pltd, 5/8-11NC-3 x 1". The bolts from the bracket to the bumper (p/n 123605) are described as 1/2-20NF.
“When a long train of abuses and usurpations, pursuing invariably the same Object evinces a design to reduce them under absolute Despotism, IT IS THEIR RIGHT, IT IS THEIR DUTY, TO THROW OFF SUCH GOVERNMENT...” -Declaration of Independence, 1776
Tom P
CPL
CPL
Posts: 148
Joined: Sat Oct 20, 2007 4:01 am
Location: Fairview Hts. IL.
Contact:

Re: LU-4 Winch-to-Bumper Bracket Bolts

Post by Tom P »

Just a thought
Was common to drill out damaged holes to 9/16 and re-tap.
Could be the case?
Tom
"47" WDX WW
"52" M37 WW
"54" Willys M38A1
"65" M35A1 WW
To Many Others
http://www.g741.org/photogallery/main.p ... temId=2019
Elwood
MSGT
MSGT
Posts: 937
Joined: Mon Oct 24, 2011 9:34 am
Location: Water Winter Wonderland

Re: LU-4 Winch-to-Bumper Bracket Bolts

Post by Elwood »

Tom P wrote:Just a thought
Was common to drill out damaged holes to 9/16 and re-tap.
Could be the case?
Tom
I'd be very hesitant to drill a hole tapped for 1/2-13 in aluminum and try to go to 9/16-12. The minor diameter of a 9/16-12 thread is less than the major diameter of a 1/2-13 thread.

A more likely repair would be a thread insert such as a Heli-Coil or a Timesert. The eight side mounting bracket stud female threads (9/16-12) in the aluminum clutch housing and worm housing covers of the LU-4 winch I've been working on were badly worn, so I repaired them all (plus quite a few other female threads elsewhere on those housings) with Heli-Coil inserts. Not an easy (or inexpensive) task, given that the threads for the studs are recessed, and required a special Heli-Coil bottom tap to get enough threaded length in the housing to screw the insert in. But the thread insert will be stronger than the original thread of the same size in aluminum.
“When a long train of abuses and usurpations, pursuing invariably the same Object evinces a design to reduce them under absolute Despotism, IT IS THEIR RIGHT, IT IS THEIR DUTY, TO THROW OFF SUCH GOVERNMENT...” -Declaration of Independence, 1776
just me
1SG
1SG
Posts: 1195
Joined: Fri Nov 28, 2014 4:25 pm

Re: LU-4 Winch-to-Bumper Bracket Bolts

Post by just me »

I was dead tired last night and reversed the bolts when I typed. looked this morning and they are 5/8 in the top to the winch and 1/2 in the bottom to the bumper. (The 9/16 were the side studs.)
"It may be ugly, but at least it is slow!"
Elwood
MSGT
MSGT
Posts: 937
Joined: Mon Oct 24, 2011 9:34 am
Location: Water Winter Wonderland

Re: LU-4 Winch-to-Bumper Bracket Bolts

Post by Elwood »

just me wrote:I was dead tired last night and reversed the bolts when I typed. looked this morning and they are 5/8 in the top to the winch and 1/2 in the bottom to the bumper. (The 9/16 were the side studs.)
Thanks for checking on the bolt sizes.

Now I just have to figure out why the female threads in the aluminum housings will not accept a 5/8-11 bolt.
“When a long train of abuses and usurpations, pursuing invariably the same Object evinces a design to reduce them under absolute Despotism, IT IS THEIR RIGHT, IT IS THEIR DUTY, TO THROW OFF SUCH GOVERNMENT...” -Declaration of Independence, 1776
just me
1SG
1SG
Posts: 1195
Joined: Fri Nov 28, 2014 4:25 pm

Re: LU-4 Winch-to-Bumper Bracket Bolts

Post by just me »

I just pulled one to make sure. They are ⅝-11 X 1.5". All 4 holes int the face of both of my winches (m37 an M715) are ⅝-11.
"It may be ugly, but at least it is slow!"
Elwood
MSGT
MSGT
Posts: 937
Joined: Mon Oct 24, 2011 9:34 am
Location: Water Winter Wonderland

Re: LU-4 Winch-to-Bumper Bracket Bolts

Post by Elwood »

just me wrote:I just pulled one to make sure. They are ⅝-11 X 1.5". All 4 holes int the face of both of my winches (m37 an M715) are ⅝-11.
Thanks again, just me.

Looks like I'll be ordering the Heli-Coil 5/8-11 kit and one of their special 5/8-11 bottom taps on Monday.
“When a long train of abuses and usurpations, pursuing invariably the same Object evinces a design to reduce them under absolute Despotism, IT IS THEIR RIGHT, IT IS THEIR DUTY, TO THROW OFF SUCH GOVERNMENT...” -Declaration of Independence, 1776
NAM VET
1SG
1SG
Posts: 1118
Joined: Mon Aug 22, 2016 6:27 am

Re: LU-4 Winch-to-Bumper Bracket Bolts

Post by NAM VET »

I recently painted my LU4, and re-aligned the top plate, and found the holes in my aluminum tops were a bit stripped. So perhaps yours are just partially stripped threads too, and need some gentle persuasion to take a bolt
NV
Elwood
MSGT
MSGT
Posts: 937
Joined: Mon Oct 24, 2011 9:34 am
Location: Water Winter Wonderland

Re: LU-4 Winch-to-Bumper Bracket Bolts

Post by Elwood »

NAM VET wrote:I recently painted my LU4, and re-aligned the top plate, and found the holes in my aluminum tops were a bit stripped. So perhaps yours are just partially stripped threads too, and need some gentle persuasion to take a bolt
NV
Thanks NAMVET. The top plate holes on both left and right housings of my winch were almost stripped, too. Probably assembled repeatedly without any anti-seize between the steel fastener and aluminum housing. I ended up putting Heli-Coils in all of them.

The 5/8-11 female threads in the front faces of the housings are just the opposite: they're too tight to accept a 5/8-11 bolt. A 9/16-12 bolt fits, but feels loose, looser than a 1B fit. I think I'll just drill the housings and Heli-Coil them for a 5/8-11 thread.
“When a long train of abuses and usurpations, pursuing invariably the same Object evinces a design to reduce them under absolute Despotism, IT IS THEIR RIGHT, IT IS THEIR DUTY, TO THROW OFF SUCH GOVERNMENT...” -Declaration of Independence, 1776
Post Reply