Diff leaks? (visual included)

[martinlbb]

Hi guys,

I'm doing a full maintenance of all hydraulic parts (brake, clutch, diff locks...). It's amazing to see that such jobs can be forgotten for decades
Bleed was so black, I never saw that before... It looked like more mud than bleed...

However, when I removed slave cylinder (the one who engaged diff lock on rear axle), I notice a good quantity of oil escaping.

On the other side, where diff switch light is located, It is the same. Switch is diving in oil!

Is that normal to have oil on this section? Do I have a leak in diff?

See attached picture to clarify.

PS: On intermediate rear axle, I can see oil inside, but at a much lower level

[martinlbb]

Following other posts, I read this article :

https://app.box.com/s/shf5gohckchubsolgvbg

Seems that I have a leak..

Will unmount parking brake first and see!

[Jim LaGuardia]

Replace the o rings on the apply pin and sleeve, inspect for melted or loose locker switch(they leak if loose).

[Pinzcat]

I have had the same problem. I made change the o-ring by a professional but the leak remained after that. It was very strange because the leak seemed to be the same if the vehicle ran or not.
I finally discovered the reason: there is a "cork" (DIN 443) under the axis of the control fork of the diff. lock. This "cork" was badly commited and there was a leak... Easy to repair!

[martinlbb]

Thanks for your feedbacks!

OK for o-ring, I'll do it.

For your cork, I got it: this is part number 900.3139, called "Plug" (french translation is closer to cork word).

This is part number 19 on this close-up.

Thanks all for your help, I appreciate

[martinlbb]

Quick return:

I finally removed parking brake, as I wanted to verify Pinzcat info.

Finally, cork is okay, oil is only leaking from o'Ring (thanks Jim!).

But, I got a surprise. Leak is so old, that oil came inside parking beak.
Everything is covered with black and sticky oil. Nice surprise!

Wont be a problem to fix, as I know a truck maintainer practice to clean oily brake pad.

Just burn them with a blowlamp, to burn oil.
After that, put some white spirit on it, and burn it again several times.

OIl will totaly consume and keep brake pad intact.

Then you end the job with brake cleaner. Tadam, brand new brake pads!

Warning, this is not environmentally good, but this is:
* the least bad solution, because wastes are usually burned in big facility...
* I keep original (and still good) one, without re-invest money in it.

[pinzinator]

Is the o-ring part #26?

[martinlbb]

Is the o-ring part #26?

Part #6, on locker mecanism side.

Part #26 is o-ring for locker switch, and you can also change it (failure is rare, as it is not a piece subject to movements).

[martinlbb]

You can see it on Puch's online schematics:

http://www.puch.at/en/spare-parts/pinzg ... rear-axle/

This is part #5 (why did they change part number between offline/online catalogue ??). Less than 1 USD/EUR.

[ExpeditionImports]

If gear oil can get out then dirt and water can get in. Monitor you potential problems often and if you are a fan of playing submarine captain with your Pinzgauer then there is a little more maintenance. There trucks are amazing in now long they will go before they let loose. With this truck the damage was so severe even the housing was damaged. Complete loss. No it was not used as a planter.

[martinlbb]

It's incredible! Thanks for this amazing picture! (BTW, could I show it on my blog?)

Just to let peoples know, I got diff leaks. On my 6x6 712, when I drained rear diffs, I discover that the rearest one was nearly full (3/4, due to leak in parking brake). Worse, intermediate one was nearly empty (1/4). I was starting to fear!

I decided to disassemble everything on the drive line, including transfer box.

After opening them up, I understood why intermediate diff was leaking a lot. Intermediate drive shaft had been trimmed with time. This unbalanced tork propagated itself to seals, and made them totally useless.

On this same diff, a dumb man repair was done before. On axle sop ring (the one with long term grease, who apply on ball cup), oring was bad. A guy poor everything with silicon...

Fortunately, vibrations didn't propagated to axle bearings and wheels satellites. I finally changed all o-rings, driving shaft bearings (in witch hat), and intermediate driving shaft (including female receiver). Intermediate axle is expensive (1200 USD), but it is the only solution.




Before assembly, everything cleaned and checked (or changed)


"Brand" new intermediate diff. Rear diff will follow.

I also rebuild the transfer box, as it was leaking through selector fork, and I suspected a "jump to neutral" trouble. It's fine now

[Profpinz]

Whilst not as bad as Scott's example this is the original front diff of my 718 (a replacement has been sourced).

[martinlbb]

Wow!!

Dumb question: did the previous owner knew that oil as to be put in diff, not green mayonnaise sauce? Joking!

How was the dammage? Seems not to horrible. Bearings?

[Haf-e]

Must have been some special army green camouflage oil...

[Profpinz]

It was actually a mixture of oil, water, sand, mud and who knows what else.
Both front diff boots were damaged and the right was half torn away, but obviously this didn't stop it been driven and over time a "goop" just slowly developed in the casing........this only goes to prove, if you get a damaged boot, it's important to repair or replace it asap.

The water content did corrode the crown wheel, pinion shaft, etc and whilst you probably could have still used it, I opted not too (given that the whole vehicle is been restored to the best of my ability)
The Malaysian Militaries maintenance of these vehicles was not very impressive