Hi all. Got a 2004 terex t200 with 3200 hours on and every now and then when tilting or crowding the headstock the boom drops very harshly! It’s worse when your trying to do delicate work ie pick up or drop off a wobbly pallet and you just need to tilt or crowd the fork slightly it drops the boom and all delicate work is like trying to smash concrete! Not sure if it’s a possible fault with the joystick or something wrong with the valve block .ie bit of dirt in valve or valve rod sticking. Once got told there’s a valve underneath the inner boom to do with the headstock tilt and crowd. Any help or advice is much appreciated! Thanks
Terex t200 2004 telehandler
- Thread starter Rytwent
- Start date
- Location
- Moreton-in-Marsh, Glos
It’s almost certainly a problem with the joystick. Almost certainly fixable by David King Electronics, between Stratford-on-Avon and Warwick.
- Location
- Moreton-in-Marsh, Glos
I had a similar problem with the joystick on a Matbro 250 110 (who Terex bought out). David King sorted it very quickly.
- Location
- Moreton-in-Marsh, Glos
@ACEngineering is probably the expert on these things. I’m fairly certain he will agree that it is the joystick and also recommend David King Electronics Ltd.
- Location
- Oxon
Could it be a problem in the valve chest or a problem with the valve underneath the boom?Its probably not joystick
- Location
- Oxon
It might be a joystick issue but could easy be a solenoid on main valve block which is probably more common.
However your description of the problem does not fit with either of these problems imo cause the lift would only move at slow to normal speeds if solenoid or joystick fault.
Boom dropping very harshly sounds exactly like your crowding the headstock hard back against the stops and then taking weight off the main lift ram on to the self leveling ram.
When you go to tilt forward even very slightly the boom will crash down back on to the lift ram. This is kind of normal but can be made alot worse by worn main lift ram pins and bushes and worn main boom pivot bearings.
Plus it has alot to do with the operator! Or rather a mechanically unsympathetic one not understanding how the self leveling system works and putting the machine in the situation in the first place which causes great stress on all the boom pivots and tilt circuit.
There is no wear in anything on the machine at all and I’m very experienced with driving it and do not give the machine a hard time. It’s definitely not an issue with crowding the headstock back to far! This fault can happen when the headstock is halfway or anywhere between full tilt or full crowd. It’s definitely not getting crowded back to far! It’s as if there’s 2 services getting worked at the same time even though your only doing one! When the boom drops harshly it drops twice as fast as it does when emits working normally!
- Location
- Oxon
Well if theres no play on the bushes it can only drop harshly and twice as fast as when in normal use like your describing if theres no oil in the ram or its leaking badly past piston seal or past the lock out valve or if it has air in the ram.
So start by resealing the lift ram and maybe chance the lock out valve on the side of lift ram.
A quick test to at least check part of the solenoid cross feeding to 2 services is to turn off the tilt on the isolator switch. The hold the tilt leave in either or both directions and watch to see is the boom moves up/down. Cant remember which it does if theres fault but it's always the same way.
