Keeping the M38a1 E-brake with an overdrive

Deadguy · Post by **Deadguy** » Sat Aug 20, 2011 3:15 am

I know Wes had a good suggestion on this, basically using a cable instead of the rod system, but does anyone have any instructions on both how to do this, and maybe even photos?

12Bravo · Post by **12Bravo** » Sat Aug 20, 2011 5:11 am

Here is a thread on the subject from G503.com http://www.g503.com/forums/viewtopic.php?f=88&t=153952, hope that helps

Deadguy · Post by **Deadguy** » Sun Aug 21, 2011 11:03 pm

having a cable with a guide tube is a great idea. Does anyone know where I can find a length of cable and a guide tube? Especially in generic sizes that match up?

Post by **wesk** » Mon Aug 22, 2011 10:43 am

You use a short length of steel brake tubing found at any auto parts store. You use a length of 1/8" or 5/32" stranded steel cable (7 - 19 [7 strands with 19 wires in each] type is best). This can be found at aircraft supply stores and farm supply stores and many hardware stores. The crimpers are a bit expensive but you can substitute hammer and a piece of steel angle or plate to swage the ends on the cable.You use the brake line fittings and a couple of brake line unions to fasten the tube at each end to the necessary brackets that you fabricate.

That G503 thread has my photo on it and I'll post it here too:

In the photo below you can see various ways to terminate the wire rope at each end:

These oval swages are the most common used:

These thimbles save wear on the wire rope:

This is a cross section of wire rope:

You can find these swaging tools around $50 at farm supply stores in the fencing section:

LeeG · Post by **LeeG** » Mon Apr 23, 2012 9:32 am

I know it was not original but so nice to have.

After years of waiting, I finally purchased a new OD from Herm and got it installed last week. He accidentally sent me the wrong shift linkage so I don't have the shifter in place but I manually engaged it and went for a short drive this weekend. WOW, that was really nice to go 50-55mph and not have the motor screaming at me. It was so much quieter and needed, since I rebuilt my motor a few years ago and don't want to kill it. I have to drive on a highway (55 is the speed limit on Louisiana State Highways) for about 12miles before I get to town or just about anywhere else.

Does anyone have any pictures of their parking brake with the overdrive installed? I want to do as little modification as possible but the hole in the floor is almost directly over the drive. The drive is about 1/2" or less under and I'm having a hard time visualizing how a cable and tube could make this bend. It looks like I would have drill a new hole closer to the handle to mis the top of the OD. I just need a little more ammo before I go at it.

artificer · Post by **artificer** » Mon Apr 23, 2012 1:08 pm

Here is another link that may help you out with suggestions of easier ways to get things done.
http://www.g503.com/forums/viewtopic.ph ... e#p1004215

Post by **wesk** » Mon Apr 23, 2012 3:10 pm

John that web site seems to only address the OD shift lever not the emergency brake operation on the M38A1.

LeeG · Post by **LeeG** » Fri May 04, 2012 1:13 pm

Bump please.

Pics of actual install anybody?

LeeG · Post by **LeeG** » Thu May 10, 2012 12:07 pm

Here is a view of how close the overdrive is to the floor and how much the line would have to be bent to go around the overdrive.

Post by **wesk** » Fri May 11, 2012 12:00 am

1/8" 7x19 stranded steel cable will tolerate 90 degree bends in it's guide tubing. 3/16" or 1/4" guide tubing can be used.