FLU419 SEE HMMH HME Owners group

[FarmMOG]

Couldn't that one be sealed with silicone?

A friend is working on our John Deere tractor and he gave me some anaerobic gasket maker, which is what they use at the dealership. He said the best thing to use is Honda Seal, which Honda uses to seal most of their components on an engine. Of course, I had just finished making and installing a new gasket, so will try the gasket maker on the next one.

 

[The FLU farm]

Getting tired having to clean the fuel strainer about 5 to 10 times a day, I finally drained the tank, pulled it out, and pressure washed the inside after soaking it with ZEP de-greaser. All the bacteria/fungus crap came off and only some slight surface rust remained.

Based on what I've read, you may have rinsed out all the resulting evidence of the bacteria/fungus, but the source may well still be there in the system.
Either way, it should take a while before you need to clean out the strainer again.

 

[The FLU farm]

A friend is working on our John Deere tractor and he gave me some anaerobic gasket maker, which is what they use at the dealership. He said the best thing to use is Honda Seal, which Honda uses to seal most of their components on an engine. Of course, I had just finished making and installing a new gasket, so will try the gasket maker on the next one.

Yeah, those anaerobic gasket makers can be pretty bulletproof, especially when used with the correct prep stuff.
Didn't want to chance it when putting the creeper kit in my tractor so that's what I used. Mostly because there's 15 gallons of expensive fluid in there, not "cheap" AW-32.
But hopefully you won't have to worry about "...the next one".

 

[alpine44]

Based on what I've read, you may have rinsed out all the resulting evidence of the bacteria/fungus, but the source may well still be there in the system.
Either way, it should take a while before you need to clean out the strainer again.

I treated the tank with Biobor JF about a month ago. While this biocide will stop new growth, it cannot remove the detritus of the previous contamination.

I will keep adding Biobor JF to any new fuel to hopefully keep this annoying crud from reappearing.

 

[The FLU farm]

I treated the tank with Biobor JF about a month ago. While this biocide will stop new growth, it cannot remove the detritus of the previous contamination.I will keep adding Biobor JF to any new fuel to hopefully keep this annoying crud from reappearing.

Ah, you did it in the opposite order of what I did, aka the correct way. I cleaned and cleaned, then started using Biobor. Haven't checked the strainer recently, but the fact that the SEE now runs for at least an hour or two (instead of 10-20 minutes) is a good sign.
My tank cleansing was nothing like yours, so a little crud will likely keep showing up in the system. Come to think of it, with the right wand(s), it may work to pressure wash the tank in place. That could be helpful for those of us with the tank mounted too high for easy removal.

I also added Biobor to the storage tanks. It's one thing to get fungus in the relatively simple fuel system of a SEE, but I'd hate to think what it'd be like to deal with in modern, finicky diesels.

 

[peakbagger]

I had to pull the bottom outlet on the front hydraulic tank and replace the gasket due to a large leak since purchase. Found out they don't sell the replacement gasket, but found a local shop that would make one. After draining the fluid and removing the old gasket, it turns out the home made cardboard gasket was in bad shape so I just bought some new rubber gasket material and made a better replacement myself. Leak check all looks good, so hopefully no more drips. Almost every fluid except hydraulic has been changed. Only have the brakes and transmission oil and I will call it finished. Looking on line for transmission fluid, I found Red Line Synthetic MTL 75W80 GL-4 Gear Oil or equivalent. Does anyone know if this is the type to use? Thanks.

Sorry I am a bit late to thread. Its a bit of a rabbit hole on the transmission fluid question. The military used GL-5 to standardize on lubricants as the portals and diffs should have GL5. Thus if you follow the military's lead you would use the same fluid in all three. On the other hand Mercedes specs GL4 for transmissions as GL5 eats synchronizers. I talked with a retired Case/Unimog mechanic at one point and he mentioned that he spent frequent visits at the depots helping to rebuild SEE transmissions with worn synchros. Most SEEs barely have break in mileage so the synchronizer wear may not be apparent due to GL5 use. Amsoil used to push GL5 for everything until they came out with GL4 specific for uses in transmissions that require it and they now offer a synthetic with GL4 additives. Thus its a crapshot, My late production 1990 1300L was built just about the same time as the SEE (but a later model) and it is definitely a GL4 application. So it comes down to if you follow the military spec you are believing Uncle Sam knew best, but if you believe mercedes folks they suggest GL-4. I plan to change my SEE over to GL-4 next spring.

By the way even the experts get confused, the transmission fluid is actually gear oil and is typically used for assembly that dont have synchronizers, thus many companies list GL5 as acceptable for GL-4 applications. Its only in this odd place that GL-4 is the way to go. Apparently some Toyotas and Nissans also have this issue.

 

[FarmMOG]

I read the previous post and associated article about this last night. It seems like there are a lot of different opinions about what is actually GL4 or GL5 among the experts. Talked to a friend and he visited with the engineers at his company that sells oils and lubricants and has found a new product that they all say will work great for this. It is Shell Spirax S6 GXME 75W80. I am getting a 5 gal bucket, (smallest unit available) and will have some for the next change as well. It specifically states it is good for syncro transmissions, so will see.

 

[The FLU farm]

Well, there are lots of transmissions living happily with engine oil in them, as per the manufacturer.
But probably few of them are as costly and hard to replace, putting the FLU trannies in a different league.

 

[alpine44]

The applicable manufacturer's specification for lubrication of the vintage Unimog gearboxes is MB 235.1 and several brands are listed there.
Before we worry about the availability of the listed lubricants in the USA let's look on the German Unimog forums what oils have been recently used and evaluated for their shift behavior:

(The list below was taken from here and translated. Last update: March 2017)

Type/// mm/s² 40°C /// mm/s² 100°C /// rough shifts when

FUCHS titan gear mp 80 /// 92 /// 10 /// warm (too thin, when warm)
Cartechnic GL4 SAE 80W /// 90 /// 10,5 /// warm (too thin, when warm)
RAVENOL GL4 MZG SAE 80 /// 90,9 /// 10,7 /// warm (too thin, when warm)
LiquiMoly GL4 SAE 80W /// 95,2 /// 11 /// warm (too thin, when warm)
bp Energear EP 80W-90 /// 133 /// 13,8 /// warm (too thin, when warm)
Cartechnic GL4 SAE 80W-90 /// 153 /// 15,3 /// shift mostly well
Rektol Gear 300 SAE 80W-90 /// 140 /// 16 /// shifts very well according to user "martin-w"
RAVENOL GL4 TSG SAE 75W-90 /// 76,3 /// 14,2 /// optimum shift behavior according to user "OPTIMOG" and "KLAUSi". Does not attack yellow metals at 100°C.


Both RAVENOL oils are available in the USA directly from ravenolamerica.com or - in case of the supposedly best performer GL4 TSG - from Amazon.
I am probably going to give the RAVENOL GL4 TSG oil a try. RAVENOL GL4 MZG SAE80 is listed in MB 532.1 but did not get much user praise. In fairness, MB did most likely not anticipate that their customers would run Unimogs for hours on the Autobahn.

After reading a lot of articles regarding EP additives, GL-4 vs GL-5 specifications, and several TDS/MSDS, I would also be comfortable using
Sta-lube CRC 85W90 (NAPA Part#: SL24239)
Redline MTL 75W80, MT-85 75W85, or MT-90 75W90

I am confident that these are safe for the yellow metal in our gearboxes; what remains is the question about the best viscosity.
Does anyone have any real life experience with the listed Sta-Lube or Redline oils?

 

[The FLU farm]

Interesting observations, alpine. My concern here would be that people have different standards about what's good, bad, or indifferent, when it comes to how a transmission shifts. And to make things more "uncomparable", it's different transmissions.
Each of mine shifts a bit differently, and there doesn't seem to be any direct correlation between mileage/hours on them and their degree of smoothness or being balky. They all have the Govt. issue fluid in them.

I have seen no reason to change the transmission oil, and for my usage they would probably work fine with olive oil in them. Never driving longer distances, or fast, is not ideal since they probably never reach a decent operating temperature, but heat would not be an issue. Using GL-5 wouldn't be a problem, either, since it doesn't much matter to me if a transmission is synchronized or not.
As long as whatever is in there keeps the bushings, bearings and gear contact surfaces happy, I'm not losing any sleep over what it is...when they're driven like mine are. Your results may definitely vary.

 

[peakbagger]

The resident Unimog expert in NH (and possibly the east coast ) is George Bull at the Unimog Center http://www.unimogcenter.com/ . He recommends and uses Redline GL-4 only for similar vintage gearboxes based on his research. His experience is predominately with the older 406 series and the newer SBUs. He imports them so he is pretty well 25 years behind the times as that's the cut off before things get real complicated. That's why I have a 1990 1300L in addition to my SEE. In addition to selling Unimogs, he also outfits expedition Unimogs and occasionally runs worldwide expeditions so he has lived first hand what is important as these expeditions tend to be way out there in the bush with no support. His first SEE was only purchased last year so he less familiar with the SEE's but he quite familiar with most of the Mercedes components.

His opinion to me was to use synthetic GL-5 in the portals and the diffs with GL4 in the transmission. He really doesn't push synthetic in the engine, his experience is the engines are overbuilt and unless someone is doing long haul trucking, regular oil is fine.

Based on other folks experiences I also installed the drain back tubes on my front portals of my 1300L as many folks have experienced loss of oil and gear damage due to pumping of fluid up into the diff on both the 1300 series and the 406 series. It sounds like this is related to long distance driving so I expect its not needed on typical SEE

 

[alpine44]

Interesting observations, alpine. My concern here would be that people have different standards about what's good, bad, or indifferent, when it comes to how a transmission shifts. And to make things more "uncomparable", it's different transmissions.
Each of mine shifts a bit differently, and there doesn't seem to be any direct correlation between mileage/hours on them and their degree of smoothness or being balky. They all have the Govt. issue fluid in them.

I have seen no reason to change the transmission oil, and for my usage they would probably work fine with olive oil in them. Never driving longer distances, or fast, is not ideal since they probably never reach a decent operating temperature, but heat would not be an issue. Using GL-5 wouldn't be a problem, either, since it doesn't much matter to me if a transmission is synchronized or not.
As long as whatever is in there keeps the bushings, bearings and gear contact surfaces happy, I'm not losing any sleep over what it is...when they're driven like mine are. Your results may definitely vary.

I agree that in reality it will not matter what you pour into the gearbox for most SEE use cases and considering that the machines already sat for decades with the .gov fluids in them. However, since the price difference between the "right" lubricant and a "maybe right" one is insignificant compared to the cost of changing the fluid, let alone having to repair/replace the transmission, I figure it could not hurt to find the "right" stuff.

If the synchros wear out faster with some oil, so be it. I double clutch the FLU gearbox anyway if there is any grade involved as the synchros act way too slowly to keep the momentum. But there are apparently also some brass bushings around the input shaft that could be compromised by unsuitable additives. Having to replace them is going to be a bear of a job that I am trying to avoid.

BTW: Just got off the phone with Ravenol America and will report once I receive their suggestions and pricing.

 

[alpine44]

The resident Unimog expert in NH (and possibly the east coast ) is George Bull at the Unimog Center http://www.unimogcenter.com/ . He recommends and uses Redline GL-4 only for similar vintage gearboxes based on his research. His experience is predominately with the older 406 series and the newer SBUs. He imports them so he is pretty well 25 years behind the times as that's the cut off before things get real complicated. That's why I have a 1990 1300L in addition to my SEE. In addition to selling Unimogs, he also outfits expedition Unimogs and occasionally runs worldwide expeditions so he has lived first hand what is important as these expeditions tend to be way out there in the bush with no support. His first SEE was only purchased last year so he less familiar with the SEE's but he quite familiar with most of the Mercedes components.

His opinion to me was to use synthetic GL-5 in the portals and the diffs with GL4 in the transmission. He really doesn't push synthetic in the engine, his experience is the engines are overbuilt and unless someone is doing long haul trucking, regular oil is fine.

Based on other folks experiences I also installed the drain back tubes on my front portals of my 1300L as many folks have experienced loss of oil and gear damage due to pumping of fluid up into the diff on both the 1300 series and the 406 series. It sounds like this is related to long distance driving so I expect its not needed on typical SEE

Thanks for the info. Did he recommend any specific viscosity for the Redline GL-4 oils?

 

[Another Ahab]

I have seen no reason to change the transmission oil, and for my usage they would probably work fine with olive oil in them. Never driving longer distances, or fast, is not ideal since they probably never reach a decent operating temperature, but heat would not be an issue.

Now THERE'S a wonder fluid for you. The ancient Greeks swore by it, and used it for:

- Cooking

- Lubrication

- Bathing

- Lamplight

Water might be the only fluid more useful.

Or is that beer?

http://www.foodrenegade.com/olive-oil-35-wickedly-cool-uses-for-your-home-body/
​

 

[The FLU farm]

I'd take beer over olive oil, if it's for my consumption. Machinery would prefer the oil, I think.
Olive oil saved my butt once when I ran out of gas with a 2-stroke motorcycle. A few people stopped and offered gas, but nobody had any 2-stroke oil, or any oil - until a guy from Greece showed up. I mixed a fair amount of olive oil into the gas and figured I'd dump it all out when (if?) I'd get to the first gas station.
Well, the bike ran great on it, plus it smelled good, so I ended up burning it all. Been a fan of olive oil since.

 

[The FLU farm]

However, since the price difference between the "right" lubricant and a "maybe right" one is insignificant compared to the cost of changing the fluid, let alone having to repair/replace the transmission, I figure it could not hurt to find the "right" stuff.
If the synchros wear out faster with some oil, so be it. I double clutch the FLU gearbox anyway if there is any grade involved as the synchros act way too slowly to keep the momentum. But there are apparently also some brass bushings around the input shaft that could be compromised by unsuitable additives. Having to replace them is going to be a bear of a job that I am trying to avoid.

I'm with you there. If the fluid needs to be changed, might as well use the better one for the application as long as the price is reasonable.
Should I ever end up in the situation where a trans would need repair/replacement, that FLU would instantly become a parts car. There's no way I'd spend the time and money (especially since I don't have any of either to spare) and I envy and feel sorry for those that do. Have the time and the need, that is.

 

[peakbagger]

On my 1300L his recommendation is GL4 75W90.

With respect to olive oil I expect the additive I use to increase the lubricity in my diesel is mostly biodiesel most likely made out of used cooking oil. It has no petroleum odor to it and looks like cooking oil. Unfortunately I have been told that the critters that plug up diesel fuel systems in boats can eat the oils so most boat owners avoid biodiesel. This may be a superstitious approach as the folks I have known that have battled contaminated sailboat fuel systems for years would be willing to sacrifice a goat yearly if it cured the problem. Instead they just put in huge glass visible filter bowls and carry several spare filters plus overdose the tanks with Biobor.

 

[Another Ahab]

Well, the bike ran great on it, plus it smelled good, so I ended up burning it all. Been a fan of olive oil since.

GREAT story.

 

[FarmMOG]

Continuing to fix small problems and replace most fluids. It is a long but worthwhile process. The nasty rust colored brake fluid was definitely overdue for replacement. I have noticed the front fan on the hydraulic oil cooler comes on, but the back one does not work. Haven't had a chance to look at it yet. Does anyone know if they are separately controlled by the front and rear hydraulic systems, or should they both come on at the same time no matter what? I finally was able to take the beast for a test drive down the road and put a few miles on it. When I parked it the front hydraulic tank seemed fairly hot even with the fan running. It could just be normal, but my experience with this tractor is very limited, so want to make sure.

 

[The FLU farm]

Continuing to fix small problems and replace most fluids. It is a long but worthwhile process. The nasty rust colored brake fluid was definitely overdue for replacement. I have noticed the front fan on the hydraulic oil cooler comes on, but the back one does not work. Haven't had a chance to look at it yet. Does anyone know if they are separately controlled by the front and rear hydraulic systems, or should they both come on at the same time no matter what? I finally was able to take the beast for a test drive down the road and put a few miles on it. When I parked it the front hydraulic tank seemed fairly hot even with the fan running. It could just be normal, but my experience with this tractor is very limited, so want to make sure.

The cooler is for the rear system only, as far as I can tell, as they seem to be completely separate systems. And the fans are wired together, so both are supposed to run when the temp sensor decides that they should.
I don't think I ever thought to check if the front tank got hot, but if things are working like they should, the only way I know of to make that fluid hot would be to work the loader fairly hard.
But what really makes me curious is how you ended up with the fan running after a test drive. Mine takes a decent amount of work with the backhoe at higher ambient temperatures for the fans to come on. Or, running the snow blower (which takes all the power the rear system can muster) for an hour or so. In other words, my fans rarely come on. Was your PTO accidentally engaged during the drive?

Thinking more about this, you got both the front and rear systems hot (which is subjective, except that the cooling fan came on, so that's definitely hot) which makes me wonder if there are severe restrictions in both systems. But the rear one shouldn't know, or care, as long as the PTO isn't engaged. You definitely have my curiosity pegged now.