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TAKEUCHI TB138FR Excavator losing Engine RPM when Digging

RIPMUP

Member
Joined
Jan 28, 2014
Messages
19
Location
Australia
Third owner and only 75hrs ? something seems fishie
Sorry I'm the second owner. I've run some injector cleaner and it seems to be fine. Also I think these machines like 3/4 throttle. I will check all fuel lines for any kinks to just to make sure.
 

Lil' Puss

Senior Member
Joined
Nov 24, 2008
Messages
352
Location
WA
I've run some injector cleaner and it seems to be fine. Also I think these machines like 3/4 throttle. I will check all fuel lines for any kinks to just to make sure.

Did you check for diesel bugs?
 

Lil' Puss

Senior Member
Joined
Nov 24, 2008
Messages
352
Location
WA
If you were running it at less than operating speed, around 1,800 to 2,000 r/m, there might not be enough horsepower to pop the relief valve. I had assumed (I know) you were running it at operating speed.
 

RIPMUP

Member
Joined
Jan 28, 2014
Messages
19
Location
Australia
If you were running it at less than operating speed, around 1,800 to 2,000 r/m, there might not be enough horsepower to pop the relief valve. I had assumed (I know) you were running it at operating speed.


Can you please explain the releif valve and how it works or how it should be working?
 

fsmech

Well-Known Member
Joined
Jan 15, 2014
Messages
90
Location
western australia
Occupation
field service mechanic
What type of fuel filter is fitted, does this have a yanmar engine? Would be thinking engine first before hydraulic. Will the engine completely die if you stall out a function?
 

RIPMUP

Member
Joined
Jan 28, 2014
Messages
19
Location
Australia
What type of fuel filter is fitted, does this have a yanmar engine? Would be thinking engine first before hydraulic. Will the engine completely die if you stall out a function?


It's a yanmar engine and it does not completely die, it just dropped in revs when under load and when using all 3 circuits.

I'd say it's a standard fuel filter.
 

Lil' Puss

Senior Member
Joined
Nov 24, 2008
Messages
352
Location
WA
Wasn't the issue solved by merely running the engine faster at operating speed? Say 2/3 to 3/4 throttle?
 

Lil' Puss

Senior Member
Joined
Nov 24, 2008
Messages
352
Location
WA
With the small Yanmar engine I doubt the fuel consumption is greater than 1-1/2 gallons per hour at full load and speed so I think you can take the sediment bowl/filter out of the equation, but check/clean the screen.
I digress.
 

fsmech

Well-Known Member
Joined
Jan 15, 2014
Messages
90
Location
western australia
Occupation
field service mechanic
Check the fuel tap if fitted to the filter and also the o-ring is not damaged. Havent dealt with the TAK excavator, but have the yanmars with fuel probplems in forklifts and gensets. Does it have an electric lift pump fitted or hand priming bulb?
 

heymccall

Senior Member
Joined
Feb 19, 2007
Messages
5,349
Location
White Oak, Pa
On my Takeuchi machines, w/ Yanmar engines, my illustrious operator remove the fuel filler neck screen when refueling. Then they use the fuel nozzle that's been laying in the bed of their filthy work truck. "The screen makes the fuel splash back", they say. The result is blockage of the inlet elbow at the water separator.
Anyhow, mark and disconnect both fuel lines at the fuel water separator. Loosen the bowl mounting ring a little bit. Unbolt the separator assembly from the machine, and disassemble the bowl etc from the head. Thoroughly inspect the inlet elbow for debris. Wash all the inner components and reassemble. Install on machine, connect hoses, ensure fuel lever on separator is in the on position. Turn key to run, wait 2 minutes, then start machine.

I have had the inlet filled with plastic, straw, tiny rocks, paper, and a bit of unidentifiable matter. Had the same inlet elbow bricked shut on my 350hr SVL75 Kubota.
 
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