JCB 802 (older 1985 model ) losing power problem

[GHDirect]

I am new to this forum, new to diggers and their technology, recently retired and doing a self build bungalow in Dorset.

I purchased an older JCB 802 (3.5 ton) steel tracked digger believed around 1984/5 (rumoured to be a rebadged Kubota with 3 cylinder Kubota engine) in reasonable nick having had new ram seals, hydraulic oil change in recent years and well greased. (filters unknown status) but no service manual.

Everything working great for a few hours then suddenly the engine seemed to be straining under load and losing power yet all hyraulics still functional but almost stalling the engine.

Leave it 30 mins and it starts and revs as it should but only for a minute and the above sets in again.
Leave it 24 hrs and again it recovers typically for 30 mins before the above sets in.

I feel its hydraulic related rather than the diesel engine being the way it sets in.
Nothing obvious, nothing seized, no leaks, not over heated, hydraulic oil half full.

Need some advice as to how to locate the problem.
On such units can you easily isolate the hydraulics side from the engine when fault is on to help troubleshooting? Could the problem be as simple as bad filter in hydraulics?

Any assistance appreciated

GHDirect

[ianoz]

WElcome to the forum Mate . Sounds to me like Blocked Fuel Filters . Or Fuel lines have what is known as Banjo fittings . These fitting have a hollow bolt though them ,with some having a Gauze filter ,which can block up . Also Possible something in the bottom of the fuel tank that get sucked over the pick up . . Couple pof things to look at .

[Muz]

Hi welcome to the forum .. If it isnt fuel related do you have a stone or dirt or something stuck under a breaker pedal ?

[GHDirect]

JCB 802 Power Restored

WElcome to the forum Mate . Sounds to me like Blocked Fuel Filters . Or Fuel lines have what is known as Banjo fittings . These fitting have a hollow bolt though them ,with some having a Gauze filter ,which can block up . Also Possible something in the bottom of the fuel tank that get sucked over the pick up . . Couple pof things to look at .

Thanks for the above clue. The problem got worse which actually helped the engine would try to start and cough to a halt. I check fuel line to find the small fuel pump feeding the injector pump was not pumping as it should. Stripped and cleaned now 100%.

Restored my faith in this old unit.

GHDirect

[Wee Jim]

I had he same problem with my hitachi ex15 now I think of it! I replaced the small electric pump and it never gave any hassle again!

Glad you are on the go again!!

[Dan]

Hi & welcome fella, I didnt know those old JCB's had electric in them ?