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Hydraulic Tank leaking on dump truck

PeterG · 2023-07-02 17:14

Anyone know a company or someone that can repair or replace a steel leaking hydraulic tank on my dump truck here in Washington State. It has a slow leak near the bottom rear wheel side that is driving me crazy. FYI, 1. Tank is welded onto truck 2. Likely less than 50 gallons 3. Need someone that could drain fluid and weld leak area 4. Remove tank from truck and weld, or weld up new exact replacement. I don't think I can find a stock one 5. Best if they know how to work on Dump trucks. 6. Prefer small shop

Replies29
  1. #156wrench2023-07-03 10:51

    Who the hell welds any kind of tank directly onto a truck frame?? Cut it off carefully without causing any damage to the frame, repair the old tank, and make new mounts for it or put on a new tank with appropriate mounts

  2. #21693TA2023-07-03 12:55

    I have to find the photos I snapped of a truck that came in for a "shake" above 25mph. If you think a welded to frame hydraulic tank is bad, then universal joint cups arc welded to the rear axle drive pinion yoke would probably "take the cake".

  3. #3DDoug2023-07-03 13:44

    Is the leak from rust ? If so, do you think the surrounding metal is also just as thin ? Or is it a crack from vibration ?

  4. #492U 34062023-07-03 14:01

    Best just to buy a new reservoir if rust is the cause.

  5. #5DDoug2023-07-03 14:07

    Yup, I think this will be the decision about remove/weld in place.

  6. #6cfherrman2023-07-03 17:04

    If you find a pin hole you can center punch around it to seal it off. If you weld it with fluid in put a shop vac on it in case it burns through.

  7. #7PeterG2023-07-04 12:19

    It's off a 1990 truck. May be rust or damage from the wheels kicking up rocks. The other problem is I've thrown on some JB well which has worked at times, but I hate dripping oil on a homeowners driveway and in my parking area. ("I'm a contractor"). I think it's best to remove, sand down and inspect and likely get another one. But it's a custom fit I think.

  8. #8_Weldman_2023-07-04 13:09

    I suggest looking at Buyers Products, I'm sure that's more likely where it came from than customized. https://www.buyersproducts.com/product/upright-steel-reservoir-968

  9. #9PeterG2023-07-04 14:20

    The truck is an old California Municipal truck with two Lift cylinders that I'm sure they spec'd out. It was originally a self loader with side arms and bucket in front. That's why the dump box has a cab cover. Still, I might replace it with a Buyers tank. However, they are not oriented in the right configuration.

  10. #10PeterG2023-09-13 12:58

    Up Date. So I ended up getting a new 18 gallon tank. As it was an odd size, I had it custom made from Propower Mfg. Now I need to get it installed. The shop I normally use is busy, so it may be something I can do. Questions: 1. It will be easier access to have the box lifted. I do not have a shop or chain hoist set up to hold the box up. The truck does have two safety bars (see image), and I could add some heavy dunnage. Can I just raise the box, and then drain the fluid out of the tank then? 2. Once the tank is bolted on and the hoses attached, can I just add hydraulic fluid back in? Best fluid to use? Do I need to bleed the system and pressurize the system etc? It has a breather cap, so I assume no? Your advice and direction would be much appreciated.

  11. #11Jonas3022023-09-13 13:33

    I usually feel pretty good with a oak 6x6 across the frame rails in front of the hinges wrap a chain to keep it from sliding out if you dont trust your safety bars , all mine are rusty but yours look to be in pretty good shape No need to prime just fill it up and cycle the box a few times your good to go

  12. #12PeterG2023-09-14 11:22

    With the box up, and the fluid drained from the reserve tank, do the lift cylinders no longer have fluid in them, so the lift cylinders no longer hold the box up? The reserve tank is an 18 gallon tank. How much hydraulic fluid is likely to drain out of the whole system? There is a shut off coming off the bottom of the reserve tank leading to the filter. When would I use the shut off valve? I will replace the screw on filter.

  13. #1392U 34062023-09-14 14:09

    Oil "should" be trapped between the control valve and the cylinder. Some will probably leak past the valve spool with time but it should be minimal. Whatever you do, don't ever rely on hydraulics to hold up something, especially if you're working under/near it.

  14. #14PeterG2023-09-15 12:08

    Any suggestions on new Hydraulic fluid or just put the drained fluid back in?

  15. #15Delmer2023-09-15 12:37

    Put the old stuff back in. If the new tank is smaller than the old tank, then you need to leave the same amount of empty space when the box is up, or it might over flow the first time you lower the box. So I wouldn't add all the oil back until you know it will fit.

  16. #16PeterG2023-09-15 14:41

    The new tank should be the same size. The old tank has been leaking, so I will check that first. The old tank has a dip stick. The new tank has a sight gauge on the side.

  17. #17cfherrman2023-09-15 17:46

    If the fluid is not mixed with water then the use it. I typically try to filter with a shirt or something to get the dirt you added in back out

  18. #18PeterG2023-12-12 19:37

    I finally started this project! I have drained the old oil. I removed the hydraulic filter , but can not identify it. I took it down to Williams Oil Filter Service in Tacoma. He gave me a Baldwin BT287 spin on filter. Can anyone tell me if this filter will work, or suggest another Baldwin model? The BT287 is a low pressure filter. The lift system is a 1990 PTO Knauss-brand twin telescoping hydraulic lifts designed by Dick Knauss for International 4900 5 yard dump truck. I do not now anything about the PTO pump yet. Return Tank holds 15 gallons.

  19. #19cfherrman2023-12-12 19:41

    Is the filter on the return line? If so it's fine, other than that the only other thing that could be different is capacity.

  20. #20PeterG2023-12-12 20:15

    The system has a ball shut off valve on the bottom part of the tank, and then the housing for the spin on filter. I assume the system is designed to shut off the fluid in the tank to make it easier to just change the filter without draining everything. The other line goes to the top side of the tank as seen in the image of the new tank I posted above..

  21. #21cfherrman2023-12-12 20:46

    Follow the lines and see where they go, that must be a suction filter

  22. #22PeterG2023-12-13 13:11

    Yes, it's a suction filter. So can anyone tell me if the Baldwin BT287 will work in this application? If not, any other filter to suggest?

  23. #23skyking12023-12-13 15:14

    Your question is best directed at the guys who sell the filters. They will know what the application is. If you got it at Williams oil filter they should know.

  24. #24skyking12023-12-13 15:15

    Yes, it's a suction side filter. That's a real good candidate for a lot of cavitation if you try and get on it with cold oil and throttle up any.

  25. #25PeterG2023-12-17 18:28

    Ok, the project is completed. Thank you everyone for all your help. FYI, the custom tank came from Metal Tanks by Propower. I was able to give them dimensions and other design features and they did an excellent job. Only concern was the shipping via pallet was way too much.

  26. #261693TA2023-12-17 20:30

    That's a nice replacement tank. With the tank ends larger than the body some protection is afforded rather than just a straight butt weld at a corner. I've seen several tanks blow out from sloshing oil after several years of use and this will preclude that. Shipping most anything via truck is expensive. Fuel cost, surcharges, etc. really add up quickly.

  27. #27Coaldust2023-12-17 21:17

    Tanks for the update. That’s a sweet looking tank.

  28. #28cfherrman2023-12-17 21:49

    I'm not a fan of that long assembly sticking out on the suction, a rock or debris of some sort might get some leverage and break something, if the last tank was like that then it should be fine.

  29. #29PeterG2023-12-18 11:33

    Yeah the tank shut off handle, and spin on filter was in that position on the old tank at least for the last ten years since I have owned the truck. I have been worried about rocks from the tires hitting the return hose, and chafing below and damage. However, the hoses seem to be in good condition. I might add some hose wrap chafe material.