Handbrake replacement

[Pete Ashby]

Originally Posted by motto

In regards to the effectiveness (or not) of the Jeep handbrake. I have a friend who many years ago determined to get his to work 'as it should'. He carried out the adjustments and did in fact get the thing to work quite well. That evening we got in the vehicle to attend a club meeting and had only gone a couple of miles before flames were noticed coming up from under the floor around the levers. His response was quite impressive. We came to an immediate halt and as we exited the vehicle he was already removing his jumper which he then used to beat out the flames. My response was equally impressive, I couldn't stop laughing at the sight.
David

This made me smile, been there done that, I can't think any one who has owned a jeep hasn't had a similar experience.
Basically its a design fault in that the activating cam levers on the band are not long enough to enable sufficient leverage to be applied by an out of the dash handle. It would be a whole lot better with a conventional hand brake lever through the floor as I think from memory GP’s had.
There are four actions that can be taken to help this poor design

1. Ensure the transfer case output shaft has an effective oil seal, obvious but often over looked resulting in oil collecting in he bottom of the brake drum on standing only to then contaminate the lining.

2. Ensure the drum is true so many originals are dished ridged or distorted by heat and contaminated linings this results in the already meagre braking surface being reduced by as much as 50%. Truing up on the lath is possible if the ware is not too bad, these days it should not be difficult to obtain a replacement.

3. Check the profile of the activating cam levers these can ware down so that the already poor mechanical advantage at this fulcrum point is further reduced. Take the brake apart and build up with the mig then grind to re-profile or alternately get new repro parts

4. Fit a new cable ensuring that the curve down the fire wall is a gradual as you can make it and that the path to the hand brake is a straight and direct a possible to minimise friction, is worthwhile running a little oil down the cable before fitting

Done collectively these actions will improve the overall effectiveness of the transmission brake from B#### woeful to just acceptable, here in the UK a lot of the jeeps that tow trailers have been converted to the M38 expanding shoe brake something I have not had experience with.
The jeep was undoubtedly revolutionary in terms of design and functionality but like all things in life it was not perfect and the hand brake is a case in point.

Pete

[gary_bath_jr]

Here's a crazy idea, not sure if it will work as I do not have the parts to test, however, is it possible to insert the short end of the U up ffrom the bottom of the hole and then rotate the bolt and push it up from the bottom? Of course this will only work if the hole is not threaded and you have to put a nut on it once in place.

Gary

[Little Jo]

Originally Posted by gary_bath_jr

Here's a crazy idea, not sure if it will work as I do not have the parts to test, however, is it possible to insert the short end of the U up ffrom the bottom of the hole and then rotate the bolt and push it up from the bottom? Of course this will only work if the hole is not threaded and you have to put a nut on it once in place.

Gary

Hi Gary

Mate, I tried everything even your idea, but to no avail as there are 3 holes the bolt passes through and I must admit cutting the small hole in the floor worked a treat, too easy.

Little Jo
Tony Van Rhoda

[Yeo.NT]

Just a observation that I have come across while working on MLVWs and this applies to all MVs. Why are the park brakes kept being replaced when in theory they are designed to hold a object stationary. Since it isn't moving there shouldn't be any wear?

[Pete Ashby]

On transmission braked systems it will almost always be due to a combination of oil contamination and over adjustment to compensate. Inevitably this becomes a self fulfilling prophecy until the whole thing either catches fire or completely fails to operate.

[Little Jo]

Originally Posted by Pete Ashby

On transmission braked systems it will almost always be due to a combination of oil contamination and over adjustment to compensate. Inevitably this becomes a self fulfilling prophecy until the whole thing either catches fire or completely fails to operate.

Pete

You are right on the button there. From what I have seen with the MB Jeep there will be constant regular ongoing work due to the original design of the transmission brake.

Have a look at the photo showing the brake linings after I removed it, there was enough oil to service my lawnmower, no wonder the hand brake did not work. The other photo shows the new bonded brake linings before I re-installed it. At the moment the transmission brake works, but for how long will be interesting.

Tony
Little Jo

[Phil Waterman]

The oil serves a purpose to prevent the brake band from rusting. Keeping the lining and band well soaked in oil or gear lub prevent failure due to rust.

But all kidding aside the, the point is if the brake is correctly adjusted and never has to be applied to stop the vehicle instead of or in aid of the regular brakes it should not wear out. They due seem to get oil soaked and if you ever drive off with the brake partially engaged it will eventually let you know it or the cars behind you will when smoke starts rolling from under the truck.

I too have done a sudden stop on the side of the road diving from the cab with fire extinguisher in hand, after seeing smoke in the rear mirrors. Looking under the truck in the smoke to hear that sizzling sound like some one cooking bacon.

No flames, so I chocked the wheels released the hand brake and sat there until the whole mess was cooled down.

Cheers Phil