1. Thank you for visiting HeavyEquipmentForums.com! Our objective is to provide industry professionals a place to gather to exchange questions, answers and ideas. We welcome you to register using the "Register" icon at the top of the page. We'd appreciate any help you can offer in spreading the word of our new site. The more members that join, the bigger resource for all to enjoy. Thank you!
  2. ALL NEW MEMBERS READ THIS FIRST!! Thank you for joining Heavy Equipment Forums! If you are new to forums we communicate with "Threads", please search our threads to see if your topic may have already been answered and if not then click "Post New Thread" in the appropriate forum. This will allow all of our members to see your question and give you the best chance to be answered. After you've made a number of posts you will graduate to Full Member status where you'll see a few more privileges. Following these guidelines will help make this the best resource for heavy equipment on the net. Thanks for joining us and I hope you enjoy your stay!!

Wacker RT820 (new to me) Can't Get Started

Discussion in 'Other Compact Equipment' started by Parts, Jun 2, 2021.

  1. Parts

    Parts Well-Known Member

    Joined:
    Dec 6, 2016
    Messages:
    87
    Location:
    DMV Area
    I got a new to me Wacker RT820 walk behind articulating trench roller. The machine is CHERRY and seen really little use but when I put a battery to it I get no crank. It has a wired remote (with a battery on it). When I turn the key on the machine the remote does not light up. Do I need to get a fresh battery in the remote even though I am running it corded or should it work even though the remote battery is dead? Not sure where else to look but of course a new battery and charger is over $500 so trying to figure out if there could be something else. I do hear clicking at the fuel solenoid and some sort of click in the remote when I turn the key to the ON position - but when I push the crank button there is nothing.
     
  2. DGODGR

    DGODGR Senior Member

    Joined:
    Dec 19, 2009
    Messages:
    867
    Location:
    S/W CO
    These machines are very sensitive to low battery voltage so be sure your main battery is good first. If running remote via wire the unit should be charging the remote. Light on far left is indicating charge for remote (from main battery/rectifier). If showing green light then battery is being charged. If showing red then remote is NOT getting power through the cord. Next light is relative to communication with main board on unit. If green then remote is talking to the unit. If red then they are not communicating. Issues could be main board, cord, or remote (among others). In my experience the trouble usually lies in the cord which is the cheapest to repair (Last time I bought one it was around $300). If you need controller repairs try Carolina Electronics (only place I've found to make repairs to electronics on these units). One of the bigger issues I have with starting mine is relative to the oil pressure sending unit. It (and the connector I will refer to below) can be found on the passenger side of the engine (look for the oil filter). When it's cold out we have to by-pass the sending unit (un-plug the connector and run a jumper wire from one side to the otheror the 2-pole connector) to get the starter to engage. Once started then remove the jumper and plug it back in. Yesterday the sending unit ground wire broke off of the ring connector where it bolts to the engine. We replaced it today but we were able to simply hold the wire against ground to get it to start before we repaired it. Once started the sending unit won't stop the machine from running but it does keep the starter relay from engaging. That is another thing to check. There are (2) relays under the hood and you may want to check those as well. By the way parts on the old 820s (metal body units) can be hard to find. You may want to buy a spare/parts unit if you come across one. Voltage regulator, or rectifier (I'm not sure which it is) can be problematic. I don't recall if on the driver or passenger side of the engine compartment but it is bolted to the cover on the side. Be sure to turn off (BOTH) the switch on the remote, AND the key when you shut the machine off. Otherwise you run the risk of draining the battery.
    Over-all these are great compactors. I've had mine since '04 (bought with about 400 hours on it) and it now has about 2,800 hours on it. It takes a beating but has been pretty reliable. Be sure to change the oil in the exciters right away. Mine grenaded right after I bought it but I have not had any exciter/bearing issues since it was rebuilt. While you have the drums off be sure to put some extra hose guards on the hoses that operate the drive motors and exciters. Eventually they will rub through and it's a PIA to fix them. I also recommend that you keep an eye on the latches of the engine compartment side doors. They can vibrate themselves off. If you employ a lock on the controller compartment/dashboard lid be sure to keep the hasp closed (or in the locked position) when operating the machine. If you don't the vibration will start to "erode" the hasp of the lock until it simply breaks (yes, it vibrates that much).
    These things remind me of R2D2. "R2D2" all the way!
     
    CM1995 and Vetech63 like this.
  3. Parts

    Parts Well-Known Member

    Joined:
    Dec 6, 2016
    Messages:
    87
    Location:
    DMV Area
    Thanks so much for the help! Well the battery in the controller tests at zero voltage so when I would turn on the machine and remote the remote would not light up at all. A local shop is replacing the batteries in the remote right now. Hopefully that turns on the indicator lights and we get 2 greens. Once the battery is back in I will try to get the remote on again.

    Not to put the cart before the horse but I think I will replace the exciter oil now. The manual says I need special tools...can you describe the process so I can get what I need here thanks!
     
  4. CM1995

    CM1995 Super Moderator

    Joined:
    Jan 21, 2007
    Messages:
    10,438
    Occupation:
    Running what I brung and taking what I win
    Location:
    Alabama
    Brother from another mother DG - The first Wacker trench roller bought at auction with a new paint job and lettering back in 2015.:D

    IMG_1489.jpeg

    BTW - R2 is still pounding ground six years later. FWIW there is a repair shop for the remotes in Wake Forest, NC that is very reputable.
     
    Last edited: Jun 6, 2021
  5. Parts

    Parts Well-Known Member

    Joined:
    Dec 6, 2016
    Messages:
    87
    Location:
    DMV Area
    Found: https://carolinaelectronics.com/ ....thanks for the tip. Good to know this option exists...hoping a battery wakes up the remote and I don't need them!
     
  6. DGODGR

    DGODGR Senior Member

    Joined:
    Dec 19, 2009
    Messages:
    867
    Location:
    S/W CO
    It's been quite a while since we changed it but I don't recall needing any special tools to change the oil.

    That's an RT82! I don't think that they hit nearly as hard as the older RT820s but they are much quieter and don't sound like they are full of a bunch of loose bolts shaking inside of a metal drawer!! Did they ditch the Lambardini engine for a Kubota? I thought that you had an RT820.
    BTW, I started buying Bomag BMP 8500s. They seem to be more available in the used market and I have found a few low hour units from rental fleets at good prices. I think I paid $8k for the one I have. They are a bit heavier (harder to crane with a mini-ex) but I think that they work far better than the RTs for soil compaction. I think that the RTs work better for compacting 3/4" road base. The Bomags come w/Kubota 2cyl engines and the whole unit has proven to be quite solid. The proximity sensor is a bitch though. Anytime you get remotely close to it, it just stops. It can be particularly frustrating if one is used to running the RT.

    That's the place.
     
    Last edited: Jun 8, 2021
    Parts likes this.
  7. Parts

    Parts Well-Known Member

    Joined:
    Dec 6, 2016
    Messages:
    87
    Location:
    DMV Area
    Just in case someone else needs this information in the future: I am told by the shop in Carolina that I do not need a working battery in the remote to get the machine to run. So back to the drawing board by checking to see if there is voltage coming through the cable from the machine. From there if there is juice flowing to the remote I would guess the remote needs rebuilding or repair.
     
  8. DGODGR

    DGODGR Senior Member

    Joined:
    Dec 19, 2009
    Messages:
    867
    Location:
    S/W CO
    The problem could also be in the main board. If you had another machine nearby you could see if things work by swapping remotes, and/or cords (one at a time in a process of elimination) to isolate the problem component.
    Did you happen to ask the guys at Carolina Electronics if they can repair the mother board (machine side)?
     
  9. Parts

    Parts Well-Known Member

    Joined:
    Dec 6, 2016
    Messages:
    87
    Location:
    DMV Area
    He told me to send in remote and board. I didn't have time to remove the board so I sent in just the remote for now. Since the cord is sending voltage I am hoping the issue is isolated to the remote. He mentioned he can test the boards but if its bad that you replace them.
     
  10. Parts

    Parts Well-Known Member

    Joined:
    Dec 6, 2016
    Messages:
    87
    Location:
    DMV Area
    Sorry if I missed the answer to this but should I be able to start the engine by turning the key on and hitting the black starter button on the actual machine? The remote being disconnected the whole time - would it turn over and start?