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Mogasaurus · 10-27-2007, 08:24 AM

Steve - the house is looking great - certainly a change from when I saw it this summer.

The outer hub seals (which cause the leaks on the outside

) are simple to replace. But, there are two different seal kits since MB changed some dimensions at some point. The old seals are not easily obtainable so, if you have the old seals and modern replacements, you must also add a new "wear ring". Here's a quote, compliments of the late Jack Russell:

"Now there is one, universal seal for 737.0,1 & 747.0,1 axles. The only
"catch" is that the new seal is changed dimensionally. Circa 1978 the
factory "improved" the wheel seal. They made the inside diameter
larger. The early units have a 136.0 mm I.D. The wear ring the seal
inner surface rides on is appropriate to this dimension.

All later production uses a 140.0 mm I.D. seal, with a correspondingly
large diameter wear ring. If you are making repairs to leaking outer
wheel seals on a 406/416 and it still uses the 136.0 mm ID seal? Then
you must also change the wear ring to the new type as the old seals are
no longer available."

Replacement details can be found here:

http://www.rfspecialists.com/temp/seals/416%20final%20drive%20output%20seal%20replacement. htm

Since I don't remember where I downloaded that page from (it might be Dr Dan's), I simply mirrored it. Thanks to the original owner - come forward and I'll credit you.

The input seals are a bit tougher because the entire portal must come off. There are several web sites that detail this - it's much more work but the actual tech is pretty easy.

Before you replace the inside seals (maybe even the outside ones), make sure your hub vent tubes are clear of debris. If they're clogged, this could pressurize the internals enough to force lube past the seals. Since this seems to happen when you engage lockers, chances are the locker seals need to be replaced also (I guess you already know that

). Unfortunately, this requires disassembly of the axle itself - again, not that technical of a job, just heavy and awkward. Here's another Dr Dan page, describing the fix on a U1300 - I think the 416 axles are pretty much the same ( can anybody confirm that ??):

Unimog 1300 Air Locker Repair

10-27-2007, 08:24 AM	#2 (permalink)
Mogasaurus BenzWorld Elite Date registered: Jan 2004 Vehicle: '78 Mog 416.141 DoKa Location: IL & W CO Posts: 1,267	Steve - the house is looking great - certainly a change from when I saw it this summer. The outer hub seals (which cause the leaks on the outside ) are simple to replace. But, there are two different seal kits since MB changed some dimensions at some point. The old seals are not easily obtainable so, if you have the old seals and modern replacements, you must also add a new "wear ring". Here's a quote, compliments of the late Jack Russell: "Now there is one, universal seal for 737.0,1 & 747.0,1 axles. The only "catch" is that the new seal is changed dimensionally. Circa 1978 the factory "improved" the wheel seal. They made the inside diameter larger. The early units have a 136.0 mm I.D. The wear ring the seal inner surface rides on is appropriate to this dimension. All later production uses a 140.0 mm I.D. seal, with a correspondingly large diameter wear ring. If you are making repairs to leaking outer wheel seals on a 406/416 and it still uses the 136.0 mm ID seal? Then you must also change the wear ring to the new type as the old seals are no longer available." Replacement details can be found here: http://www.rfspecialists.com/temp/seals/416%20final%20drive%20output%20seal%20replacement. htm Since I don't remember where I downloaded that page from (it might be Dr Dan's), I simply mirrored it. Thanks to the original owner - come forward and I'll credit you. The input seals are a bit tougher because the entire portal must come off. There are several web sites that detail this - it's much more work but the actual tech is pretty easy. Before you replace the inside seals (maybe even the outside ones), make sure your hub vent tubes are clear of debris. If they're clogged, this could pressurize the internals enough to force lube past the seals. Since this seems to happen when you engage lockers, chances are the locker seals need to be replaced also (I guess you already know that ). Unfortunately, this requires disassembly of the axle itself - again, not that technical of a job, just heavy and awkward. Here's another Dr Dan page, describing the fix on a U1300 - I think the 416 axles are pretty much the same ( can anybody confirm that ??): Unimog 1300 Air Locker Repair __________________ *" It looks just like a Telefunken U47 ! "* 1978 Mog 416.141 DoKa 1971 W113 280SL Last edited by Mogasaurus : 10-27-2007 at 08:48 AM.