Ez-dump Trailer Does Not Lower Easy

Is it "power up-power down"?

Is it new? Have you read the instructions? Is the relief valve clogged?

Define the problem, don't tell us about the Ranger. Just the facts, please.

Lynlynch,

Sorry for being so vague. The trailer is bought used; I have only had it for a week. I think it is a power up and a gravity down, but I am not positive about that, how do I know if it is one or the other? There is nothing that states either way. Just the same if it is gravity down, I would think there must be something that is causing it to stick when it is fully extended, preventing it from freely lowering without needing assistance. Could it be air bound? There are no visible leeks; the hydraulic fluid is full in the reservoir when it is fully lowered. Has anyone else had a similar issue? And if so what did you do to fix this?

From the EZ-Dump web site:

Unit does not go down.

1. Down coil is bad and needs replaced.

2. Down valve cartridge needs to be replaced.

3. Connection to the down coil is bad.

Check out the web site. There may be help there. Probably an owners manual or other help.

EZ Dumper and Trailers, Truck Accessories, trailer parts and ...

In general simple systems are power-up gravitation down. To avoid a fall down there is a restriction which opens for the travel up and closes partly for the lowering. This orifice can be clogged by some dirt since it is a not new device. Try to locate where this restriction is and clean it. I had a similar case many many years ago at maintenance the operator lost this valve and when he commuted to down the whole really came as in free fall!

It is also possible if the cylinder is a telescopic one that wear leads to some wedge effect but I doubt it is the case.

Obviously a restriction, if it has one hose to bottom of ram it is power up gravity fall.

I once had a farm tip trailer that because of the return was to slow we just added TEE and a valve and dumped oil straight to gear box case in through another hole.

So valve was off going up and when lever was pushed down valve was opened to dump oil to return.

Pretty basic but simple and saved time, speed controlled by how far valve is relieved.

Bawer66,

I would be willing to bet that lynlynch nailed the problem. Sometimes the solenoid in the dump valve (coil) will stick causing no pressure release. I looked at the EZ Dump site to see if they had any troubleshooting information, but there is not much of anything besides sales pitches. The coil for this application I believe is basically an automated flow control valve that opens when energized to a pre-set flow (dump) volume. Then gravity along with the weight of the bed, lower the bed in a controlled manner.

If the coil in the valve is bad to the point where it does not open at all, the bed will remain raised until the pressure is released by some other means. This could be done by simply cracking open the hydraulic hose/line after the coil. This will result in hydraulic fluid leaking out of the connection. If you need to do this, be sure to have the bed blocked up in a way that it can not come down on you creating an injury or worse.

You may want to try leaving the fill cap loosened or off the reservoir tank to see if there may be a venting problem. Another thing (and I am just guessing because I do not have the specs in front of me) is the coil (dump valve) is probably 12 volt. You may be able to remove the coil when the bed is in the down position creating less of a safety hazard. But most I have encountered are buried in the frame and requires the bed to be at least partially raised to gain access. Once the coil is removed the bed will lower (maybe fairly fast) if the coil is defective, and there is not a secondary flow control device for safety purposes. You could check the coil on a bench with a meter and some source to provide hydraulic fluid to see if you have flow. Sometimes even if the coil (dump valves) make a clicking sound when energy is applied, they can still be defective.

There are several ways you could troubleshoot. Whatever you do, make sure you do it safely.

Guest,

Thank you. You give me credit where none is due. It sounds to me as if you know far more about this than I.

I just took a quick look at the web site and pasted some of it in.

Cheers.

Oh, BTW, why not register? You actually sound intelligent.

The above sketch shows the simplest hydraulic circuit for a low cost dumper.

If there is only one hydraulic device then in the non active position the pump delivers to the tank and the cylinder is connected to the tank as well.

When the cylinder has to lift the oil from the pump goes through the check valve and has thus almost free path to the cylinder. If the handle is released or the solenoid denegized the check valve is no more open and the flow comes from the cylinder via the restriction to the tank. This function is between the cylinder and the hose to avoid a fall down if the hose fails. Usually the restrictor is adjustable to adapt the speed to the oil viscosity (summer/winter).

If for any reason the restrictor which has low section (a few parts of a mm^2) is closed by dirt from the ram speed is either very low or even nil. It is the most probable failure.

Such simple systems have most of the cases not 2 solenoids.

If the carrier is used with several hydraulic devices possible to be used at same time then the schematics are different and more complex.

Thank you,

I will try this out. I will let you guys know how I make out with this. Thank you again for sharing your vast knowledge of hydraulics. I am new to using hydraulic rams, and I thank you both for stressing the respect needed when working on them.

http://www.youtube.com/watch?v=Plskd2eaZYo&feature=related

one of these ?

http://www.google.co.uk/search?q=ez-dumper+trailer&sourceid=ie7&rls=com.microsoft:en-gb:IE-SearchBox&ie=&oe=&rlz=1I7GZEU_en&redir_esc=&ei=8B99TNS-FJmR4ga30IjJBg

First EZ-Dumper is a manufacture. Is it a dump trailer or a trailer that lowers. On some of the trailers that lower there are position locks. It holds it in the up position after loading. Some are mechanical and some are solenoid operated. Insure that it's disengaging properly.

might be of use

http://cr4.globalspec.com/thread/29142/my-hydraulic-trailer-will-not-raise-unassisted-and-will-not-hold-once-raised

http://www.ez-dumper.com/serviceAndParts.aspx

http://www.tractorbynet.com/forums/hydraulics/139938-weak-hydraulics-bri-mar-dump.html

http://wiki.answers.com/Q/How_does_a_hydraulic_dump_trailer_work

http://science.howstuffworks.com/transport/engines-equipment/hydraulic1.htm

http://en.wikipedia.org/wiki/Hydraulic_machinery

any good with other languages ?

http://www.youtube.com/watch?v=lUyUa9EC0Kg&feature=related