Front not locking - I'd appreciate any ideas on fix

[jviers]

Greetings!

I'd like to pick your collective brains a bit if I may--any help at all is greatly appreciated.

I am assisting a friend who would like to sell a ‘73 710. The vehicle is in great shape (won some sort of military vehicle show) but he does not have the time to use it nor does he want to "dirty it up" (!?--he thinks it is too nice).

However, someone who drove the truck said the front axles did not appear to be locking. That is, when hydraulically engaged the axles are not locking even though it is in 4wd. When I drove the truck briefly the lock indicator light did not work (it apparently does some times (?)), and the front end did not “stutter” or jerk when making a tight turn either direction (with the rear locked a stutter is noticeable).

I am not familiar with working on Pinzs and wanted to get some idea of what you the experts thought. I know you can’t make a diagnosis only based on the above but some ideas would be very helpful. I did speak briefly with Thilo at T-Los here in AZ and he said it could be a relatively simple hydraulic problem or it could be a more involved, and expensive, mechanical problem (and he cannot get to it until September).

Do some of you have experience with fixes for this problem, and is it perhaps something I can tackle? I used to be a mechanic and have done a number of tough jobs; tools may or may not be a problem.

Any ideas welcome and appreciated!

Thanks; cheers, Joel

[Jim LaGuardia]

To test for engagement and or broken axle, engage 4x4 lever, and then front locker lever. Next lift front wheels off ground with engine off and in any gear, now try to rotate a tire. If one spins and one is locked, you have a broken axle on the spin side. If neither of them spin it is working , if the light is not on, check the bulb and circuits to it. If one tire spins opposite direction while turning the other, it is not engaged (locked), time to look at hydraulic controls.

Good luck

[jviers]

I appreciate the assistance with this. It seems I got some wrong info and the indicator (front lock) never did work. The owner says he checked for hydraulic pressure at the lever and slave and it was OK (how he checked he cannot remember). I'll see if I can get him to 1) pull bulb and replace with a known working one, and, 2) try the suggestion for checking lock.

Thanks again; cheers, Joel

[Foz]

Also check the electrical connection to the locker.