SK1824 Maintenance and Repairs

[mxpxer7]

Hey all,

We recently purchased a Mercedes SK1824 and are creating a laundry list of maintenance items. This list is ambitious, and honestly so far it's not going great hahah.

I have access to the EPC and WIS. The EPC is super helpful, the WIS not so much. I don't know if it's operator error but i swear my truck configuration doesn't exist (I hope I'm wrong).



Overview photo



Vehicle Info

• WDB6523031K043561
• SK 1824 AF 4x4
• OM401LA motor, 6 cylinder turbo with intercooler
• Hi/Lo Transfer Case
• 6-speed manual w/ split shift (6 "normal" gears, 6 half gears = 12 total)
• Center locking differential
• Rear lock differential

Maintenance Items

• Clean undercarriage
  • Things are leaking but it's hard to say where from exactly due to all the dirt/oil.
• Flush coolant
  • Replace radiator hoses
• Flush differential / replace seals
  • Front
  • Center
  • Rear
• Flush port axles
• Change oil/filter
• Change fuel filters
• Change air filter
• Replace belts
  • V-belt (only belt I know of so far)
• Inspect brakes
  • Determine froward work / order parts.
  • Any resources on this would help. I found this helpful so far https://forum.expeditionportal.com/threads/air-brake-canister-1993-917-af.236271/

Day1: Visually Inspect Undercarriage


The undercarriage has oil/dirt all over the place, it's high on our list to clean it. Hopefully it'll be easier to properly identify leaks once it's clean. I've been told these trucks "sweat" but I'm not 100% certain on what's normal and what's not. I feel like I have a few not so normal oil leaks.

So on todays episode of - 'is this normal' I've provided images of various undercarriage components and would love to hear your opinions if you have any.

Front Diff

• I believe I need a new seal, and have already received one from Spareto.

Below is a screen shot of the EPC showing part number for front seal.









If I had to guess what to replace if anything I'd guess the seal listed below in the EPC.




Center Diff







Ran out of attachments (continued in following post)

 

[mxpxer7]

Center Diff (cont'd)




I think if I replace the following gaskets the center diff will stop leaking.




Rear diff

• Not exactly sure if anything is needed here. There's a leak coming from the back of it but EPC doesn't show a gasket. So that makes me worry a little. It's marked in one of the photos below.

EPC shows only a front side cover. Doesn't look like the rear comes apart.

Transmission



Continued below.

 

[mxpxer7]

Brakes

• My initial thought is to tear the brakes apart and refresh them all around. This'll be near impossible I'm sure lol.
• I don't really know enough to know if I see anything concerning.
• The lines are all feeling somewhat brittle but I haven't identified any of the critical air lines yet.. Maybe they all are.
• Note, if i have my parking brake on overnight and the air system is at 8psi when I wake up it'll be like 4 or lower. Nothing air assist works until I start it and build up the pressure. Hopefully this is normal...

King Pins

• I believe the large spherical joint at either end of the front axle is called a kin pin. Could be wrong
• They look sturdy but I'm not sure if this thing is lubricated properly or if it should be leaking like it is.
• Hoping that once I clean this area up it'll be obvious where to grease or oil these.

That's all for now. I'm still poking around the engine and steering.

We're hoping to clean these areas up over the weekend. If you see anything in the pictures which sets off alarms or have any advice to give please don't hold back. I'll continue to post as I stumble my way through this.

Thanks all!

 

[VerMonsterRV]

First off, congratulations on getting your truck!

I will write more later, but I'm up early to get on a river jaguar tour.

 

[mxpxer7]

Thanks Heather and Jon, you guys have been so helpful along the way!

Enjoy the Jaguars!

 

[charlieaarons]

Does it have rear planetary hubs? Some of the 4x4 heavier MB trucks do have them.
Re the air issue, my U500 Unimog leaks down from 125-130 to maybe 100 psi for the brake circuit over days, so you have a significant air leak. The non USA MB trucks have even higher air storage tank pressure I believe, 18 bar ~ 260psi.
The transmission on mine is all air shift, sufficient pressure for that to work normally tends to take 30-60 seconds of idling. It’s 17 years old now.

 

[VerMonsterRV]

Back from the "Didn't see and Jaguars River Trip". A bit disappointed but we'll try again in the future.

Back to your patented old Mercedes rust prevention system, AKA oil leaks. In all fairness to Mercedes I would assume all old vehicles leak, I have an MGB and it is relatively rust free due to the leaks.

I would attack these in phases as to not change too many things all at the same time. But I am no mechanic so I need to go slow. Some of the parts could be changed out, other rebuilt at a much lower cost.

Starting in the front. The front ball joints in the hub will always leak grease, or should. If they are not oozing then they need grease added in both the upper and lower grease nipples. The grease gun will be used often in these trucks. The front air canisters, if not rusted out can be rebuilt cheaply. Really just taking them apart, replacing the diaphragm, a little paint and back in. Check the sprag units and how they look. Remove the drum and check the movement of the shoes, make sure they move freely and spring back into place. The hinge points rust a bit and there is a little grease in them to help stop that. The grease may be long gone. If possible ask the previous owner if they have repacked the front wheel bearings. Some people don't know this needs to be done on these trucks (I didn't until a fellow owner let me know and helped me do it the first time).

So your fill plugs. I would clean them up when you change the oils. Then if needed use a little non hardening thread sealant on them. So far this is the easy things to work on. Case seals may be a bit more difficult. Before really jumping in I would research if the gaskets are available. For some of these they may not be and might require using some liquid gasket maker. Having said that I doubt any of your leaks (as long as you keep an eye on the levels) are critical.

Onto the air leaks. Yup ours leaks down and leaks faster when it's cold. I really need to dig into it but I think it is mostly coming from air fittings at the end of the air tubes. Didn't realize this until I took things apart but they are 2 pieces with O-rings in them. My guess is 30+ year old O-rings are just stiff and cracked. For us I need to check each one and replace as needed. I know have some replacement bits I got from Europe, just need to stop long enough to dig in. Once again, it is not a show stopper as long as while driving you easily keep air pressure up. Just annoying to have to wait a bit at startup. At least it gives the engine a little time to warm up.

One other thing. Your truck is an 18 ton truck. Does it have a ride height adjustment (for loading)for the rear brakes? Our truck does, and after our rear leaf spring upgrade the rear brakes weren't doing a whole lot. I needed to make an adjustment to get them to work in unison with the fronts. Ours is a small linkage connected to the rear axle to the rear brake air control valve.

Enjoy the new (well to you ;-) ) truck. They are old and have issues like all old truck will, but they are simple and easy to fix with some basic tools.

 

[mxpxer7]

Oh dang, I'm glad I asked about the air. I was thinking it just was what it was type of thing. I was poking around some of these main arteries going to the brakes and I noticed the tubes are brittle. Once I get my bearings around that air system I'm going to just sprits the heck out of it with soap and see if i can find leaks. It looks like a lot of tubing, hoping it's not as bad as it seems. lol

For the oil leaks, glad to hear this appears to be a common amount of leakage. It's slow enough that it doesn't drip on the ground or anything so that's a huge plus. Maybe I'll just clean em up and call it good.

In terms of the ride height adjustment, what does that look like on yours? There's a knob which the previous own showed me, but he said it was just to adjust the tilt of the headlights when loaded... He didn't mention anything about brakes. There's a chance he might not have known or maybe really it does is tilt headlights.

Those are planetary gears in the rear. Crazy, I had no idea. So basically this reduces the stress on the axles and probably the differential. I was wondering what was in those massive drums.



Made a little progress on cleaning out some of the mud off the undercarriage. Going back at it tomorrow with a wire brush and and some rust oleum rust converter. I was able to unearth a ton of grease zerts on the drive shafts.


Dove off on a dirt road on my way home from the pressure washer. It's the first time we've been off road with it. So much fun! I love the sight picture from the over cab. It's pretty neat to ride on top of the front wheels.





I've also added a 1000# hoist to the rear for my DR650. The truck came with the rear rack (tied into subframe). I found this hoist at northern tool, then bolted it to a .5" steel mounting plate slipped it into the 2" receiver on the rack. She's a tad wobbly. I have a hitch anti rattle thing on its way, also going to shim the pinned connection.

It was super heavy. I needed a hoist for the hoist but all I had was my hands and bunch of ratcheting tie downs lol. Here's some pictures:





Fiancé and I, we picked up some coveralls to work in. Highly recommend lol.


Here's some rack info below.

 

[mxpxer7]

I haven't lifted the motorcycle yet. I'm waiting for some steel to show up which I'm going to turn into a spreader bar.

 

[mxpxer7]

Day 2: Undercarriage Clean Up
Today was pretty brutal. It was 90F in Bend, Oregon and we spent the day under the truck with an angle grinder and cans of rustoleum rust former.

Knocked most of the rust off and was able to paint the rear axle / springs. We'll need probably another day and a lot more beer to get it all finished up.

Here's some pictures from the day -

 

[Folgore]

that is a beautiful looking rig! I have to ask, are you based out of Central Oregon, would love to see it some time!

 

[SootyCamper]

Isnt this truck forsale again? I see it listed again on the ACME website.

 

[Roverchef]

Well that wasn't long...

 

[MogsAndDogs]

These trucks aren't for everyone. I can completely understand someone not wanting the extra work.

 

[Geo.Lander]

Hey all,

We recently purchased a Mercedes SK1824 and are creating a laundry list of maintenance items. This list is ambitious, and honestly so far it's not going great hahah.

I have access to the EPC and WIS. The EPC is super helpful, the WIS not so much. I don't know if it's operator error but i swear my truck configuration doesn't exist (I hope I'm wrong).


View attachment 793343
Overview photo



Vehicle Info

• WDB6523031K043561
• SK 1824 AF 4x4
• OM401LA motor, 6 cylinder turbo with intercooler
• Hi/Lo Transfer Case
• 6-speed manual w/ split shift (6 "normal" gears, 6 half gears = 12 total)
• Center locking differential
• Rear lock differential

Maintenance Items

• Clean undercarriage
  • Things are leaking but it's hard to say where from exactly due to all the dirt/oil.
• Flush coolant
  • Replace radiator hoses
• Flush differential / replace seals
  • Front
  • Center
  • Rear
• Flush port axles
• Change oil/filter
• Change fuel filters
• Change air filter
• Replace belts
  • V-belt (only belt I know of so far)
• Inspect brakes
  • Determine froward work / order parts.
  • Any resources on this would help. I found this helpful so far https://forum.expeditionportal.com/threads/air-brake-canister-1993-917-af.236271/

Day1: Visually Inspect Undercarriage


The undercarriage has oil/dirt all over the place, it's high on our list to clean it. Hopefully it'll be easier to properly identify leaks once it's clean. I've been told these trucks "sweat" but I'm not 100% certain on what's normal and what's not. I feel like I have a few not so normal oil leaks.

So on todays episode of - 'is this normal' I've provided images of various undercarriage components and would love to hear your opinions if you have any.

Front Diff

• I believe I need a new seal, and have already received one from Spareto.

View attachment 793349

Below is a screen shot of the EPC showing part number for front seal.

View attachment 793345




View attachment 793348


If I had to guess what to replace if anything I'd guess the seal listed below in the EPC.

View attachment 793350


Center Diff

View attachment 793352

View attachment 793353



Ran out of attachments (continued in following post)

Like how methodically you are working! I only have mental lists of stuff I need to do but I should make some decent plans like this!