Manitiou 741

[forblue]

bucket locking pin problem at moment they will come out but not in, engine under load when coming in but nothing trying to go out, switch has been swooped with boom one, no good, have tried moving wires about but no good when i tried it just a few days ago worked perfect, have been told its the slice, [ not cheap] anything else i can try............

 

[Fergieman]

Have you swopped the 2 pipes at the front to reverse the process?

 

[Pan mixer]

Our 627 does that, it was grit in the valves we think.

 

[benny6910]

bucket locking pin problem at moment they will come out but not in, engine under load when coming in but nothing trying to go out, switch has been swooped with boom one, no good, have tried moving wires about but no good when i tried it just a few days ago worked perfect, have been told its the slice, [ not cheap] anything else i can try............

On my 05 741 I had a similar problem but with the boom, it was some form of controller for the proportional controls. They are at the back right hand side of the cab under the trim. You can swap them around to check if it solves the problem before you buy a new one. Sorry I carn’t remember what they are called but it was a couple of years ago and a lot of water has passed under the bridge since.

 

[forblue]

Yes swapped pipes over at front when fault first occurred last year and it worked for some time have not tried it again,as there is no movement of hoses on front when trying to retract pins, there is the other way so no pressure getting there, will look at swapping over pipes on boom valve to see if this fixes it....

 

[ACEngineering]

bucket locking pin problem at moment they will come out but not in, engine under load when coming in but nothing trying to go out, switch has been swooped with boom one, no good, have tried moving wires about but no good when i tried it just a few days ago worked perfect, have been told its the slice, [ not cheap] anything else i can try............

its probably the solenoid valve knackered, is it pre 2010 by any chance? its very common.

Could also be the wiring at the base of the joystick but most of the time its the solenoid which is £770 plus vat from manitou

you can unplug it and swap with the extension, to test the wiring and the roller on joystick etc. but i wouldn't unbolt and take the solenoids off and swap around you will end up damaging the tiny thin section orings on the good extension solenoid and then you will be wanting a seal kit which is over £100 i think.

 

[ACEngineering]

The look like this. If you have a later 2010 machine then they use totally different solenoids and to date never had to replace one.

 

[ACEngineering]

bucket locking pin problem at moment they will come out but not in, engine under load when coming in but nothing trying to go out, switch has been swooped with boom one, no good, have tried moving wires about but no good when i tried it just a few days ago worked perfect, have been told its the slice, [ not cheap] anything else i can try............

These comments isnt making sense IMO.
"at moment they will come out but not in, engine under load when coming in but nothing trying to go out"
then you say
"as there is no movement of hoses on front when trying to retract pins, there is the other way so no pressure getting there"

first comment suggests engine under load but no movement. So in answer to this i would say the check valve in the locking pin ram is stuck or sticking. remove the ram and in the back is a shallow headed hex plug, under that is a check valve.

second common suggests no pressure at all retracting pins!? in which case if pre 2010 is will almost certainly be the solenoid valve i mentioned before. You can easy fit that yourself, its only 4 small cap screws and a electric plug but there is instructions on a PDF document telling you how to fit it with out knackering the orings. Which i email to anyone that buys one if they haven't fitted one before.

 

[Timbo]

I bet he has the pre 2010 valves and its spooled in one direction and stuck either having thumbed the roller or from previously with the engine labouring.

Sometimes switching off and leaving it afew mins or letting it warm up some more will see normal service resume.

I also had to replace the same solonoid (MLA 628) at vast cost, and soon discovered that the operator was not wiping or covering the aux connectors and the odd bit of crap was getting in - first port of call the delicate valve- theres obviously no filter at this stage. He had to leave and we've had no problem (3yrs) since. They do wear out, but are very sensitive to anything in the oil .

 

[forblue]

Should have said pins are in locking position and if you roll switch i can see hoses move and engine under load but when trying to retract pins nothing happens, no movement, no hoses move and engine not under load, its a 2006, 735, looked at wrong one in my book.

 

[ACEngineering]

Should have said pins are in locking position and if you roll switch i can see hoses move and engine under load but when trying to retract pins nothing happens, no movement, no hoses move and engine not under load, its a 2006, 735, looked at wrong one in my book.

it will be the solenoid valve but check by swapping the electric plug with the boom extension first. take plastic trim off in back corner of the cab then under that is a metal panel. Only 2 button headed allen screws to remove them both. solenoids are directly under there.

 

[ACEngineering]

I bet he has the pre 2010 valves and its spooled in one direction and stuck either having thumbed the roller or from previously with the engine labouring.

Sometimes switching off and leaving it a few mins or letting it warm up some more will see normal service resume.

I also had to replace the same solonoid (MLA 628) at vast cost, and soon discovered that the operator was not wiping or covering the aux connectors and the odd bit of crap was getting in - first port of call the delicate valve- theres obviously no filter at this stage. He had to leave and we've had no problem (3yrs) since. They do wear out, but are very sensitive to anything in the oil .

from about 2005 they started fitting a pilot filter on both the MLA and the MLT, but imo it didn't make a jot of difference its the electrics part of the solenoid that fails not the valve, unless the orings are knackered from poor fitting and swapping etc.

They all already have a filter in the oil supply to them anyway, if you remove the pilot feed pipe off the first solenoid block and take the male male fitting out, get a big flat bladed screw driver up inside the hole there is a gauze filter hidden in there

There was several part number changes in the early years, early ones were truly awful and the later one better but still not great.

 

[forblue]

Just to update this, checked it yesterday and swapped over plugs with boom one still same fault, changed it back buck tried moving plug connection when rolling switch and it started working used some contact cleaner and retried ok at moment if it go's again will scotch-lock a bypass wire on each wire in turn till i find one causing problem, unless someone can tell me what each colour wire is for,thanks..........

 

[Mrs Brown]

Thers a multi connector at front bottom right hand corner of the cab we had problems with ours not wanting to operate aux hydraulics which are just the hitch pins pipes swapped around IYSWIM