FLU419 SEE HMMH HME Owners group

[LZahariev]

Update on the weather stripping. I found the right fit. Looks and works like original equipment. I found it at Advanced Auto Parts but I'm sure it can be found elsewhere for much cheaper.

 

[LZahariev]

Below is the picture of the packaging that includes brand and model.

 

[The FLU farm]

A year or two ago somebody mentioned the possibility of a second warning beeper, somewhere in the system.
Well, when taking apart the switch box for the loader and high rpm to fix a switch, guess what I found?

That means that the backup alarm one can go bye bye, and there may still be a warning for low oil pressure, high temp, or whatever this one is supposed to shriek about.

 

[alpine44]

A year or two ago somebody mentioned the possibility of a second warning beeper, somewhere in the system.
Well, when taking apart the switch box for the loader and high rpm to fix a switch, guess what I found?View attachment 715364

That means that the backup alarm one can go bye bye, and there may still be a warning for low oil pressure, high temp, or whatever this one is supposed to shriek about.

This buzzer is supposed to alert the operator of problems when sitting in the backhoe seat (from which the warning lights and buzzer in the cab are not noticeable). The test button on the dash is to verify the functioning of that buzzer. You have to hold the test button for a while to make the buzzer go off - if it is working. My rear buzzer is shot but I at least get 24 Volt on the wire during the test. Since the original part is Unobtainium for reasonable money I am thinking to replace it with two cheap 12 Volt buzzers wired in series.

 

[The FLU farm]

That's what I thought it was supposed to do. But I don't have a clue about what positions the light switch levers should be in, or what moon phase we need, or whatever else it takes to make it work - or to test it.
I do remember reading that it'd take a while after depressing the test switch, and I think the clutch had to be depressed. Either way, I have never managed to make anything happen when pushing the test switch. Guess it's time to get the book out and try again.

Also didn't know that those things were hard to come by. The back-up one does work (which is one reason I hardly ever have any switches turned on), so at least I have a spare.
Maybe running the wires for the back-up beeper to a cheap strobe light, like the ones I have above the cab, would be a better solution? That way it would be obvious (to most somewhat coherent people anyway) that the machine is there and doing something, but without making me and anybody else within earshot having to hear the beeper. It'd also be a far more effective warning for when doing the only thing I do where a warning would be warranted, which is backing out from a driveway when plowing snow, or running the snow blower. For that, the beeper is useless anyway as people tend to have their windows rolled up in the winter.

Yeah, I think I'll spend $20, plus the magnets, on another strobe light. Silence can be priceless.

 

[FarmMOG]

I just had to put a jumper around my clutch safety switch. It quit working and I was tired of pulling the doghouse off and jumping the starter every time I wanted to start it. It was also time today to replace the unloader valve with a new one. I sure didn't think that there could be so much junk in the main airline, but a bunch sure came out, along with a few parts from the broken unloader. The alcohol line that was leaking finally broke when taking everything apart, and sure has me thinking about putting an inline air dryer and take out the alcohol injection. Has anyone else had any luck doing this and what model would you recommend? Thanks.

 

[The FLU farm]

So now you, too, are curious about what the relay that the switch (now wire) activates?

I need to look into what's going on with the HMMH's air system. The last two times I've used it, the unloader keeps "puffing" every 10 seconds or so. Obviously the air isn't getting to the tanks as it should.

But I did get a mower unloaded the easy way today. Not sure how I ever got along without a crane.

 

[peakbagger]

I got the parts to install an air dryer, just haven't found the time. My 1300L has an air dryer and I plan to try to copy the system. The biggest PITA is dealing with the multitude of thread types used by Mercedes to plumb it up. I have a wabco model with built in air pressure regulator.

The question I need to figure out is a source of purge air. The dryer needs a blast of dry compressed air every so often to regenerate. The question is can I pull it out of one of the existing air tanks or do I need to install a dedicated one?.

 

[Brents347]

Trailer brake air

Hey guys, I need some help. I am through page 242 of this thread and haven't found it talked about yet. If it somewhere in the next 100 pages, I apologize in advance for covering this topic again.

I have a FLU, and I have everything operating well but I now have a military trailer with air brakes and have found that the glad hands on my FLU are dead. No air pressure. I have looked through all the schematics and parts breakdowns that I can find, but I haven't figured out if maybe there is a ball valve somewhere that turns off the trailer air system when it is not needed?

The Pull knob in the cab between the seats seems to be dead as well. It does click up and down about 1/8" but doesn't actuate any air. Maybe there is air getting to that valve, but the valve is failed?

Edit; When on the (left) drivers side of the truck, the front air tank is charged but the smaller rear tank by the back tire is not.

Any help greatly appreciated.

Brent

 

[The FLU farm]

Brent, I sounds like you already found the problem. If memory serves me, that rear tank is for the trailer brakes.

Good luck, and welcome!

 

[Skidpad]

Brent, I have a similar issue on my SEE. I think that FLUs right in regards to the rear tank. One thing I definitely know is that the valve immediately adjacent to them (on page 4-313 of TM 5-2420-224-20-2) is the valve that supplies air to the trailer brakes. It strange that you asked this question tonight because I'm actually sketching up an air line schematic for myself to try and clean out the whole system now that I have some time to myself again. Let me tell you that you'll be amazed at the amount of debris that build up in our air lines. The good news is that Wabco is still making all the valves (I think) that are used so you can get direct replacement for those that are too far gone corroded (see attached picture of one of the valves on mine before TLC). You may also want to check the protection valve on page 4-332. It also has lines that go to the read gladhands.

If I finish this schematic of the whole system at a glance this weekend I'll post it.

Good luck!

 

[The FLU farm]

View attachment 716024

Ick!!

 

[Brents347]

Looking into this further, what is the 'tandem valve' that is located under the hood near the fuse boxes? It is part of the air system, but I have no ideas what it does.

Looks like I get to go figure out how to get the trailer air supply valve out from under the cab without tilting the cab as the manual suggests.

Good times!

 

[The FLU farm]

I would try to figure out why you don't get air to the tank that supplies the trailer valve before worrying about the valve itself.
At least I'd think it works that way.

 

[Skidpad]

Brents, the valve under the cab is pretty inaccessible without tilting the cab. Like FLU said, I'd definitely rule out all the easy stuff first. My advice would be to treat this like a plumbing issue or an electrical short. I.e.- start at the compressor (source of power) and work your way out to ensure that you have air along the way until you don't, then you have an idea of where the blockage is.

I'm not sure it if was FLU or Peakbagger who was recently talking about how difficult some of the air fittings can be to get off without twisting the entire airline due to a heavy application of CARC. I did find, while doing some of my repairs, that a combination of CNC Freeze-Off/ PB Blaster/ and Kroil will more or less dissolve the CARC so that you can actually loosen any troublesome fittings. Also, I'd spend $20 and get a cheap set of airline wrenches to get a better bite on those so you don't round them off.

Just my 2 cents of course. This air line thing is really the only thing afflicting my SEE which is why I've been meaning to diagnose it for over a year. I'm interested to hear what you figure out. In the meantime, I'm going to keep working on a comprehensive schematic of the air system that hopefully will allow a dumb grunt like me to figure it out. Cheers!

 

[FarmMOG]

Brent, I have a similar issue on my SEE. I think that FLUs right in regards to the rear tank. One thing I definitely know is that the valve immediately adjacent to them (on page 4-313 of TM 5-2420-224-20-2) is the valve that supplies air to the trailer brakes. It strange that you asked this question tonight because I'm actually sketching up an air line schematic for myself to try and clean out the whole system now that I have some time to myself again. Let me tell you that you'll be amazed at the amount of debris that build up in our air lines. The good news is that Wabco is still making all the valves (I think) that are used so you can get direct replacement for those that are too far gone corroded (see attached picture of one of the valves on mine before TLC). You may also want to check the protection valve on page 4-332. It also has lines that go to the read gladhands.

If I finish this schematic of the whole system at a glance this weekend I'll post it.

Good luck!

I tried to buy some from Freightliner and was told they are in the computer but not able to be ordered. Went online searching for them with no luck. Ultimately ended up rebuilding the exact one you posted the pictures of. They are very simple to rebuild, but a royal pain to remove, as everything has to be put on and taken off in order. I ended up almost taking off all the airlines in that area before I could unscrew the regulator. Be very careful when you put it all back together again, as I adjusted the regulator for a little too much air pressure, and must have blown a hose somewhere as none of the air driven accessories work now. Haven't had time to try and search for the problem, but hear air purging under the center console when driving it now, so it should be a small area to find the problem.

 

[peakbagger]

A few air system comments (I have made before but they are buried in the thread. There are some very useful diagrams of the air systems student manual in the miscellaneous technical manuals section of the forum. Here is a llnk https://www.steelsoldiers.com/showt...cavator-flu-419-manuals-and-a-student-handout.

With respect to taking the rats nest of air lines down near the air tanks apart, Be careful removing the fittings, definitely not the place for crescent wrenches, pick up a set of metric flare wrenches and combination wrenches for the big stuff. You do end up taking quite few fittings apart to get where you need to go. The paint sprayed on the air lines tends to really penetrate into the fittings. The actual metal of the some of the fittings is some sort of zinc product and don't take abuse well. I crushed one and snapped one trying to get them apart. Some of the fittings are also quite custom like tees with two females and one male end that are not readily available.

I haven't chased Wabco parts yet, I just cleaned the crud out of the fittings as I found them. I have seen comments in the Benz world forums that Wabco parts are available elsewhere in the world. I suspect its the US side of Wabco that cant get the parts. It may be that the trick is to have a dealer in Europe see if they can chase them down as Wabco seems to be far more prevalent. Perhaps check with our German member on this forum, MIgginsbro? to see if he has dealer that he uses.

 

[The FLU farm]

As a rainy day project, I finally got around to make 20-foot extension hoses for the tool reel. Now my projects will likely require 41 feet of reach, not just 21 feet.

 

[Skidpad]

Hey guys, as a follow up to the air line conversation and Wabco/Meritor parts. They are available through authorized dealers or online. I don't know about freightliner as they may not be fully tied in. Also, it appears that last year in September Wabco bought out Meritor so everything is consolidated under the Wabco brand (per a press release anyway). Here is a link to the part I replaced just for a reference to their online catalog.

https://www.meritorpartsxpress.com/...&pageView:list&minPrice:&maxPrice:&pageSize:&

To strongly echo what peakbagger said, be extra slow and methodical when disassembling the air system as it was obviously assembled by german magicians with access to alien technology...

Thanks for the link to the student handout. This must have become available since I was last active as I've spent the last 12 months rebuilding a house.

Cheers!

 

[peakbagger]

Great news on Wabco, I expect I will be chasing down a few parts at some point.

Some other member posted the handout. I just made sure it got to the technical forum so it wouldn't disappear. It is incredibly helpful for diagnosis.