[Pedr]

G'day Darryl,

Have had similar experience with steering a carrier on loose surfaces. Especially turning right but not left easily.

The first and major repair that we undertook was to have the drums machined and the shoes rebonded with NOS pads. This has made an unbelievable amount of difference.

Another carrier that I worked on had all of the steering setup to the letter as described in the manual. I remember that one thing that we found that was critical was to start by setting up the steering column and steering wheel exactly as described. We started at first with the column one tooth out on the spline and it made a huge difference and had to start again. The spider on the bottom of the steering column must be parallel to the front edge of the drivers seat. and the spokes of the wheel need to be horizontal as they act as a sort of artificial horizon.

Another issue that can cause headaches with steering is track. It is important to have both sides equal in length. If one side is even marginally longer or tighter than the other, it will impact on your steering. In my experience the best way to overcome the length problem is to remove both tracks, lay them out side-by-side, and check the length. They should be identical. The manuals list the method to remedy this if they are not the same.

Track tension is another matter, but nearly as important to get even. My suggestion is to count the number of teeth interlocked on the track pawl. They should be even on both sides. This may take some amount of upper body strength and mind you don't hurt your back. ( It'll need some lifting )

You may also need to check your cam followers. With the steering column set in the correct position, your cam plate should be parallel to the steering spider, and the cam followers should be equidistant on the cross-shaft, with the bogies lined up with the remainder of the track wheels on the track, That is to say not biased to one side or the other. If your cross shaft is not even left to right, you might have tracking/steering problems built into the system.

I am of the opinion that all of this, is and will be an ongoing problem. I think that, as the brakes are required for both steering and stopping, and ofcourse we operate the steering more than braking, continous wear and heat will be a concern and must have been whilst they were in service(**). I have seen many carriers with grooved and or glazed drums and pads, and had difficulty in removing drums due to a deep groove on the edge of the drum. This I think is a weakness in the design of carriers and probably lead to the developement of differential steering in more modern variants like M113's. So, adjustments to steering and brakes will be a constant maintainence item similar to oil, water and battery.

Hope this is of some help, sorry that it's a thesis.

Pedr

( **, Has anyone ever asked a veteran carrier driver about what maintenance issues they had to attend to regularly involving steering and brakes? and if so could you post some comment here, Thanks )