JCB 804 SUPER EXCAVATOR

JWHITBECK · Feb 21, 2019

After gets warm house and bucket will not work tracks and blade keep working fine HELP

MSM · Feb 22, 2019

Sounds like one of the pumps is failing. Machine should have 2 pumps, one for the upper functions(boom, bucket,stick and swing) one for travel/blade. Doubtfull it is a relief valve,filter or charge pump as it would be slow when cold and all functions would be failing. Need to put a set of gauges on it and test pressures

JWHITBECK · Feb 22, 2019

Thanks for help Its almost like electric kicks off cools down and works Is there a elec beaker that keeps pump engaged ? THANKS AGAIN

AJ. · Feb 22, 2019

Doubt if the pump has failed but in case it has pull the filter and see if there are any traces of metal,the pump is two stage,piston and gear,the piston section for the equipment and the gear for the servo,the most likely thing that could be wrong is the safety lock out and like you said probably the solenoid,look around the armrest for the switch and see it's closing properly,I cannot remember where the solenoid is but it will be on the servo side,the reason the tracks and blade work is they are manual operated,if you have the manual or parts book look for the cut out solenoid,it usually cuts out the servo power so it should be on that circuit.
AJ

JWHITBECK · Mar 1, 2019

Replace cut out solenoid no difference loses elec at that The papers we have says there is 50A breaker can,t seem to find that Can,t locate fuse box now I,m sure we have seen that before Does same thing as if you turn key off THANKS FOR ANY HELP

AJ. · Mar 1, 2019

Hold up on buying parts till you find out exactly what is needed as I know parts are not cheap,the fuses should be under the console on the right in an oblong box,my first advise was for you to check the switch that at the lock out lever,the lever I am talking about is the one you have to push down by the door and lift it up in order to get out,make sure the arm rest is going down fully and the lever as well,the lever when its down pushes a switch closed (on),power goes through it to the solenoid,if if the lever is not closing the switch the hydraulics are locked out.
AJ

JWHITBECK · Mar 8, 2019

Found fuss block Someone put under floor pan Still have not found 50A breaker

AJ. · Mar 8, 2019

I can't remember ever seen a circuit breaker but that does not mean it has not got one and there is a thermal breaker that can act up like you say,call JCB's and ask for advise,if it does have one they should be able to tell you where it is located,usually on all machinery the electrics is accessible and not hidden I cant believe you have to remove the floor to replace a fuse,don't you have a handbook and manual,you need them if you are going to do your own repairs.
Good luck
AJ

JCB 804 SUPER EXCAVATOR

JWHITBECK

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MSM

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JWHITBECK

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AJ.

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JWHITBECK

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AJ.

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JWHITBECK

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AJ.

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