Hey everyone, New member here. My apologies if I've posted this in the wrong subforum, but it seemed fitting as there are a few other bucket truck-related threads in here so hopefully you guys can help me out here. Recently, my boss decided that we needed to buy a bucket truck, the theory being that we will use it to help us with our rental properties and our low voltage installation business. The truck we picked up is a 2003 International 4400 with an Altec body and (I think) Allison automatic. I'm not sure the exact model of body, as I have not been able to find any data plates with a model number on them. The truck was previously owned by Kea Energy and came to us with a Oklahoma title. We bought it knowing the boom didn't work. The auction in Louisiana didn't give any specifics (of course), and the price was right, so we brought it home. The truck is fantastic! Drove 4 hours home to Mississippi without a single issue. However, this boom issue is driving me insane. I don't know anything at all about bucket trucks, and my knowledge of the underlying IC chassis is limited to my experience installing low-voltage gear on IC school buses. Here's what I know works. When you put the PTO on (brake in > trans to drive > turn PTO switch on > trans to neutral), the PTO engages and (to my knowledge) is working correctly. You can raise and lower the outriggers just fine and the engine idles up and down in response to the outrigger controls. When you flip the diverter valve at the rear of the truck to the boom controls, this is where things start acting up. The boom fails to respond to input from the controls at the base of the boom or the bucket. Let's start at the base of the boom. I can hear what sounds like either air or hydraulic fluid in the valve body while playing with the control levers and when I flip the lever from lower controls/purge/upper controls to purge, I can hear noise like it is purging something. I can see that the boom is attemping to rotate when commanded, but not with enough power to do anything. Engine RPM does NOT raise in response to the controls at the base of the boom. Moving to the bucket itself, I can get some slight response out of the jig and winch controls, but both are slow responses. I've also confirmed the safety switch is working as it will disable all controls when pressed. The joystick seems dead, and pressing the trigger does not adjust engine RPM. The boom will slowly attempt to rotate when commanded from the joystick, but like at the lower controls, it is very very slow. Here's what I've done. I did replace the hydraulic filter today and I topped off the hydraulic tank to the full line on the dipstick with everything stowed and the truck off. This did seem to improve my outrigger responsiveness and speed, as well as improve the speed of the jig moving. I did observe what looks like a small air line snapped off of some type of sensor or trigger at the base of the boom, but I believe this is the switch for what I think is a electric backup pump at the base of the boom. When the truck is running, there's no air coming from either the line or the solenoid. There's also an unknown red 12-24ga wire detached here with a spade connector on it. And thats about it really! It's a really clean truck and I can't see much evidence of leaks anywhere or anything major that would be the source of my woes. I've been playing with it for 3 days now and really haven't made any progress. I'll attach some photos for reference. Thanks in advance! Brandon
Are there any switches or wires on the outriggers?
I do believe that there is some type of switch on the outriggers, but I can't access them I don't think. I'm not by the truck at the moment to go get some photos either.
If there is you will have an enable valve electrically controlled that makes sure the boom doesn't move until outriggers are down. I have seen many , some need to be down. some need some weight on them
A 2003 probably did not have outrigger interlock switches. Is ther e a data plate on the pedistal? can you post a pic of it if there is? Is there a tool lever with the outrigger switches that energises a pair of hydraulic quick couplers on the rear of the truck? it will stop the upper hydraulics if it is engaged. Is there hydraulic quick couplers at the bucket? If the lever that activates them is engaged none of the upper controls may work.
So that's what my mystery third lever is at the passenger side outrigger controls. I do have the third lever and the quick couplers. I also have the couplers at the bucket. I've messed around with the tool switch at the bucket and have figured out that it works. Keep in mind that I do have very very slight hydraulic pressure going up, as the boom will attempt to rotate but only about a half inch in either direction. The jib will also move, very slowly, and the cylinder that controls the bucket's vertical rotation will also move when commanded, very slowly. If I press the trigger on the bucket joystick, I can hear a noise down below, but I'm not sure what the noise is. Sounds like maybe a pump engaging or something. The truck will rev up when any of the outriggers are triggered but won't rev up when any of the boom/bucket/lower pedestal controls are messed with. I can hear what sound like very weak pressure in the valve assembly at the pedestal. Today I repaired a very small air line that ran to an air switch inside the pedestal that had broken off and reattached a wire to the air switch. I believe this line runs to the plunger in the bucket that controls an electrical pump as this did not resolve any of my issues.
Can you post the model of the lift? What is that lever just to the right on the quick couplers in the picture? There should be a control valve on the turret that is controlled by the valve at the bucket. It has levers on it that will allow you to control the boom from the turret. It will have a selector valve on it as well to select between upper and lower controls. The selector has to be in the upper position for the controls at the bucket to work. There is an interlock trigger in the upper controls handle that has to squeezed into the handle for the upper hydraulics to work. The plunger at the bucket will start and stop the engine. If you push it to stop the engine and continue to hold it ten seconds and the electric pump should kick in until you release the plunger.