Benford Terex TV1200 Roller problem.

[V8Druid]

Put all back together tonight and primed her up got her fired, started up not bad and cleared no bother. Little leaks on the fuel lines sorted out. Running as good as she ever has while I've had it. Still smokes a bit on stars up but runs away not to bad. It's was either the stuck pin thing or bad fuel/leaks. Will do for now. What a beut she is
View attachment 16159
She's no oil painting but really handy to have around the yard for odds and sods. And yes the whole shed shakes when the vib is one out in the yard

's an old master i'd like in me gallery for sure ..... could put it down with one o' they on the job

 

[Quattromike]

I do like this crane about a meter from full reach and she started beeping , I reckon I could pick it up over the back end if I had to. Must be a good 2.5 ton this thing

 

[V8Druid]

View attachment 16169

I do like this crane about a meter from full reach and she started beeping , I reckon I could pick it up over the back end if I had to. Must be a good 2.5 ton this thing

if not substantially more ..... 's a big roller

 

[Regy53]

120 rollers are usually 2.7/8 ton

 

[CPS]

The little pin next to the injector pipe is that the excess fuel button? The one on the left was stuck in for some reason.

View attachment 16127

It's freed off now but not sure what it does without opening it up more. I dunno if it's meant to come right through as there is a hole all the way through. I'm not sure what is meant to be holding it in place, you can pull it out now
View attachment 16128
Never got it tested as also decided the fuel filter was a bit questionable so getting that changed out and gave the tank a drain out. Was a bit of crud in it.

Not sure what it is, but it seems to have cured your problem I'd say run her for a bit and see how she goes.

 

[Vadder]

Hi everyone! Maybe anyone have a similar expereence? Mine benford 120 of early 00's have a fault of "stop running" when hydraulic system warming-up for working temperature (after 20 ~ 30 or 40 minutes, depends from outside temperature). So we checked out brakes (simply unmounted all of them) and checked flow and pressure on two ports (A, B) of A10VG28 transmission pump. It have 150 bar and normaly changes between A and B ports when steering lever puting on reverse or forward position. Pressure constantly 150bar before / after faulty, except flow what putting down from 30 lpm to 0 lpm. Return line constantly 7 bar as drain constantly 2 bar. Firstable I though about one deffective motor that could be stop all roller, but I disconnected two motors one by one (put circuit to short) and all the same - front motor have similar fault as rear after warming up system. I think now that it can be transmission pump, but today had contact with poclain dealer who is told me about cause of fault motor and give me instructions about properly ckeck them. Tommorow will check again. Have anyone idea?

 

[doobin]

Hi everyone! Maybe anyone have a similar expereence? Mine benford 120 of early 00's have a fault of "stop running" when hydraulic system warming-up for working temperature (after 20 ~ 30 or 40 minutes, depends from outside temperature). So we checked out brakes (simply unmounted all of them) and checked flow and pressure on two ports (A, B) of A10VG28 transmission pump. It have 150 bar and normaly changes between A and B ports when steering lever puting on reverse or forward position. Pressure constantly 150bar before / after faulty, except flow what putting down from 30 lpm to 0 lpm. Return line constantly 7 bar as drain constantly 2 bar. Firstable I though about one deffective motor that could be stop all roller, but I disconnected two motors one by one (put circuit to short) and all the same - front motor have similar fault as rear after warming up system. I think now that it can be transmission pump, but today had contact with poclain dealer who is told me about cause of fault motor and give me instructions about properly ckeck them. Tommorow will check again. Have anyone idea?

I take it you mean the roller stops moving rather than the engine stops running?

 

[V8Druid]

Hi everyone! Maybe anyone have a similar expereence? Mine benford 120 of early 00's have a fault of "stop running" when hydraulic system warming-up for working temperature (after 20 ~ 30 or 40 minutes, depends from outside temperature). So we checked out brakes (simply unmounted all of them) and checked flow and pressure on two ports (A, B) of A10VG28 transmission pump. It have 150 bar and normaly changes between A and B ports when steering lever puting on reverse or forward position. Pressure constantly 150bar before / after faulty, except flow what putting down from 30 lpm to 0 lpm. Return line constantly 7 bar as drain constantly 2 bar. Firstable I though about one deffective motor that could be stop all roller, but I disconnected two motors one by one (put circuit to short) and all the same - front motor have similar fault as rear after warming up system. I think now that it can be transmission pump, but today had contact with poclain dealer who is told me about cause of fault motor and give me instructions about properly ckeck them. Tommorow will check again. Have anyone idea?

welcome Boyo .. can't help I'm afraid, but someone might have some ideas

 

[jd6820]

Hi everyone! Maybe anyone have a similar expereence? Mine benford 120 of early 00's have a fault of "stop running" when hydraulic system warming-up for working temperature (after 20 ~ 30 or 40 minutes, depends from outside temperature). So we checked out brakes (simply unmounted all of them) and checked flow and pressure on two ports (A, B) of A10VG28 transmission pump. It have 150 bar and normaly changes between A and B ports when steering lever puting on reverse or forward position. Pressure constantly 150bar before / after faulty, except flow what putting down from 30 lpm to 0 lpm. Return line constantly 7 bar as drain constantly 2 bar. Firstable I though about one deffective motor that could be stop all roller, but I disconnected two motors one by one (put circuit to short) and all the same - front motor have similar fault as rear after warming up system. I think now that it can be transmission pump, but today had contact with poclain dealer who is told me about cause of fault motor and give me instructions about properly ckeck them. Tommorow will check again. Have anyone idea?

Check the solenoid on the pump in your picture. Once the machine stops is that solenoid coil hot to touch? The terex module controls this solenoid to lock out drive. It'd be my first port of call.

 

[Vadder]

I take it you mean the roller stops moving rather than the engine stops running?

Hi, yes stops the roller not the engine. And it's stops when all hydraulic system warming up for working temperature. I checked singly front and rear hydraulic transmission motor all the same as they working as a pair.

 

[Vadder]

Check the solenoid on the pump in your picture. Once the machine stops is that solenoid coil hot to touch? The terex module controls this solenoid to lock out drive. It'd be my first port of call.

Yes I checked it, and it have a normal coil temperature and it works - when I disconnecting plug, pressure on operating port low down from 150 to 0 bar. But interesting thing when fault comes, the boost pressure on the (pilot) PS port is 22 bar - as belive to scheme flow from auxulary pump comes to PS line across solenoid, and across bypass valve to line port A or B(differents from lever position), but pressure is 0, strange vey strange.

 

[V8Druid]

Yes I checked it, and it have a normal coil temperature and it works - when I disconnecting plug, pressure on operating port low down from 150 to 0 bar. But interesting thing when fault comes, the boost pressure on the (pilot) PS port is 22 bar - as belive to scheme flow from auxulary pump comes to PS line across solenoid, and across bypass valve to line port A or B(differents from lever position), but pressure is 0, strange vey strange.View attachment 18789

faulty PRV somewhere allowing it to dump when the oil's thinned out ??? ..... presumably this is a VD pump ... what's the delta pressure like and is it consistent? if you're losing delta the pump won't upstroke for flow ... pressure could be there but virtually no flow ???

 

[jd6820]

Looks to me like you've diagnosed your own problem! The auxiliary pump you refer to is more commonly referred to as a charge pump. It's job as you are probably already aware is to supply pilot pressure to any valves in the system, release the brakes and maybe most importantly keep the closed loop drive circuit topped up with oil pressure. You get leakage in even the best motors and pumps. The charge pump will keep the oil pressure "charged or topped up" hence the name charge pump I guess? It is a gear driven pump internal to the main piston pump, not one of those mounted on the rear. They are for vibrate and steering. I'd say when it gets warm the charge pump isn't keeping up with internal leaks? Hence the low side pressure dropping. The main piston pump is running out of oil to supply the motors... The charge pump is only small and just spec'd right for the job so the first component to show signs of wear. Make this pump too big and you generate unnecessary heat in the hydraulics and lack of efficiency because it is constantly regulating excess flow back to the tank. The designers want maximum performance and efficiency so the pump is spec'd just enough and not a lot of scope for wear....

Worth checking the charge pump they are easy to get at once pump removed. Not sure if you can get to the pilot pressure regulating valve on that model externally, that I suppose could be dumping oil pressure when warm or enough to cause a problem? But generally they are either open or shut, so I think your pressures would be low even when cold? But an easy thing to check before diving too deep.

 

[Vadder]

Looks to me like you've diagnosed your own problem! The auxiliary pump you refer to is more commonly referred to as a charge pump. It's job as you are probably already aware is to supply pilot pressure to any valves in the system, release the brakes and maybe most importantly keep the closed loop drive circuit topped up with oil pressure. You get leakage in even the best motors and pumps. The charge pump will keep the oil pressure "charged or topped up" hence the name charge pump I guess? It is a gear driven pump internal to the main piston pump, not one of those mounted on the rear. They are for vibrate and steering. I'd say when it gets warm the charge pump isn't keeping up with internal leaks? Hence the low side pressure dropping. The main piston pump is running out of oil to supply the motors... The charge pump is only small and just spec'd right for the job so the first component to show signs of wear. Make this pump too big and you generate unnecessary heat in the hydraulics and lack of efficiency because it is constantly regulating excess flow back to the tank. The designers want maximum performance and efficiency so the pump is spec'd just enough and not a lot of scope for wear....

Worth checking the charge pump they are easy to get at once pump removed. Not sure if you can get to the pilot pressure regulating valve on that model externally, that I suppose could be dumping oil pressure when warm or enough to cause a problem? But generally they are either open or shut, so I think your pressures would be low even when cold? But an easy thing to check before diving too deep.

You right, today I disconnected all "interfering" lines to transmission pump and measure booster pressure, on cold was only a 10 bars that comes to 0 by time of warming up hydraulic system. So yes auxullary pump broken! Also I decided to check why pressure was 22 bar on booster (pilot) line and found another two faulties. First it's "Tow valve", that in "drive" position open flow from steering unit to boster (pilot) PS line on transmission pump. So steernig pump turning to a little support for auxullary pump, and thats why on booster (pilot) line was always 22 bar. Secondary fault shows themself, when I disconnected b1 (brake line) from "Tow valve" for a pressure gauge, I started riding for testing and watch as a hydraulic oil leaks from dissconnected brake line. So broken oil seals of two transmisiion motors made a leakage of "drain" line to brake chambers.

 

[Vadder]

faulty PRV somewhere allowing it to dump when the oil's thinned out ??? ..... presumably this is a VD pump ... what's the delta pressure like and is it consistent? if you're losing delta the pump won't upstroke for flow ... pressure could be there but virtually no flow ???

Well it was several faulties, first and main auxulary pump of main transmission pump and broken "Tow valve" that works incorect, in "drive" position puting flow from steering unit to booster line - that's why was always 22 bar, and interfered with diagnosis. In "tow" position it closing all flows.

 

[bigdigger77]

Hi jumping on the thread here if its ok?
I have had a TV1200 for several years and only use it infrequently, gone to do a job with it and the travel speed has got very quick , just a small movement of the lever and its off in both forward and backwards. Lifted each drum in turn and both rollers power around ok and no strange noises. Everything else works ok, is there a hi and low speed function I'm missing ? any ideas welcome ?

 

[Mick-the-fitter]

Looks like the rollers are from one side of the swash plate bearings, therefore there wouldn’t be a neutral position of the plate, as the end of the plate would move about inside the pump with no bearing. Hence as soon as the lever is moved from neutral position the roller moves backwards instead of forwards.