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I need help!

deereresurrector

Active Member
Joined
Mar 11, 2017
Messages
28
Location
Crockett, TX
Occupation
technician
I have posted and threaded with little to no responses. on a Kobelco sk300lc mark iv I am having the engine stall out and die . checked the single pump solenoid, and replaced . Is it surpo0se to buzz or click when 24 volts is added. I have power to solenoid and it is new . If I extend any function all the way or stall out hyd s it will kill engine or bogg it down. In d mode it will dig at idle no problem till cylinder rod hits the end of its stroke. then it will stall out engine . Not sure if that is normal . Also in the other mode functions if I barly move stick It will stall engine quickly and kill it. s h and fc kill it easily d mode will only kill it if you stay on hyd for about 4 seconds after it is at end on its stroke. does this make any sense to any one. YCU- 1127. Please some one educate me.
 

Tones

Senior Member
Joined
Mar 15, 2009
Messages
3,101
Location
Ubique
Occupation
Ex land clearing contractor, part-time retired
It may not be a hydraulic problem. I suggest you first check the fuel system to insure the engine is producing proper power including the screen in the banjo fitting on the lift pump.
 

deereresurrector

Active Member
Joined
Mar 11, 2017
Messages
28
Location
Crockett, TX
Occupation
technician
OK this is what else I have done complete engine service, and hyd service. This one has the cummins engine. So all filters changed . On primer pump is screen on in ley or outlet. It was ca weird looking primer. not sure if its oem. no I didn't check it. Runs like a spotted ape with no load. but it does make sense.
 

thepumpguysc

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Mar 18, 2010
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7,562
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Sunny South Carolina
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Master Inj.Pump rebuilder
I have to know what engine & fuel system is in it before I can help..
MOST fuel systems have whats called a "torque back up".. that's what engaged when you reach the end of your stroke..
It increases the fuel and holds the governor to prevent the engine from shutting down.. under those momentary loads..
There is also a dump valve in the hydro system, that may not be working/set properly.. and unless you put gauges on the system, and take readings, your pizzing in the wind..
 

Tones

Senior Member
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Mar 15, 2009
Messages
3,101
Location
Ubique
Occupation
Ex land clearing contractor, part-time retired
It's something I learn't many many years ago. An outfit I was working with had a 769B Cat dump truck that was really gutless. They played around with the transmission trying to get it going better and spent heaps of $ guessing and finally got a Cat tech in.He found the engine was short of 300RPM, adjusted the throttle and Bob's yer uncle fixed It.
So even check the rubber fuel lines coming from tank and the strainer in the tank. When you are 100% sure the engine is OK then start pressure testing the hydraulic's starting at the pumps as this will give you a bench mark pressure
 

deereresurrector

Active Member
Joined
Mar 11, 2017
Messages
28
Location
Crockett, TX
Occupation
technician
I have to know what engine & fuel system is in it before I can help..
MOST fuel systems have whats called a "torque back up".. that's what engaged when you reach the end of your stroke..
It increases the fuel and holds the governor to prevent the engine from shutting down.. under those momentary loads..
There is also a dump valve in the hydro system, that may not be working/set properly.. and unless you put gauges on the system, and take readings, your pizzing in the wind..
It
 

deereresurrector

Active Member
Joined
Mar 11, 2017
Messages
28
Location
Crockett, TX
Occupation
technician
It's something I learn't many many years ago. An outfit I was working with had a 769B Cat dump truck that was really gutless. They played around with the transmission trying to get it going better and spent heaps of $ guessing and finally got a Cat tech in.He found the engine was short of 300RPM, adjusted the throttle and Bob's yer uncle fixed It.
So even check the rubber fuel lines coming from tank and the strainer in the tank. When you are 100% sure the engine is OK then start pressure testing the hydraulic's starting at the pumps as this will give you a bench mark pressure
It has the in line 6 cummins ycu 1127
 

deereresurrector

Active Member
Joined
Mar 11, 2017
Messages
28
Location
Crockett, TX
Occupation
technician
So there is a strainer in the tank?! I have went through lines leaving primer pump and disconnected and resealed all connections. So also on inlet on primer pump has a screen? On a banjo fitting. I have not checked that yet and haven't checked strainer in tank.
 

deereresurrector

Active Member
Joined
Mar 11, 2017
Messages
28
Location
Crockett, TX
Occupation
technician
I have to know what engine & fuel system is in it before I can help..
MOST fuel systems have whats called a "torque back up".. that's what engaged when you reach the end of your stroke..
It increases the fuel and holds the governor to prevent the engine from shutting down.. under those momentary loads..
There is also a dump valve in the hydro system, that may not be working/set properly.. and unless you put gauges on the system, and take readings, your pizzing in the wind..
I will retrieve injection pump # as well as engine codes on serial # plate Thank you.
 

deereresurrector

Active Member
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Mar 11, 2017
Messages
28
Location
Crockett, TX
Occupation
technician
I do know there is a bit of farm yard engineering on fuel shut off solenoid . I wired back in solenoid so they dont have to pull a cable to get it started . Without a doubt that crap wasn't OEM.
 

Tones

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Mar 15, 2009
Messages
3,101
Location
Ubique
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Ex land clearing contractor, part-time retired
I wasn't aware that it's Cummins powered. All I have ever seen is Isuzu or Mitzi engines in them. Maybe it's been repowered. Most Jap excavators I have come across have a screen in the tank,screen in the banjo bolt going into the lift pump. I have also come across fuel hoses that have delaminated internaly mainly on older gear and can never be seen just by looking at the outside..All these thing I would be looking at before buying any parts.
The only I could find doing a real quick search on the engine is it's made in China. I maybe wwwrrrrooonnnggg.
 

Kobelco ireland

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Feb 28, 2016
Messages
449
Location
Ireland
Occupation
Mechanic
I wasn't aware that it's Cummins powered. All I have ever seen is Isuzu or Mitzi engines in them. Maybe it's been repowered. Most Jap excavators I have come across have a screen in the tank,screen in the banjo bolt going into the lift pump. I have also come across fuel hoses that have delaminated internaly mainly on older gear and can never be seen just by looking at the outside..All these thing I would be looking at before buying any parts.
The only I could find doing a real quick search on the engine is it's made in China. I maybe wwwrrrrooonnnggg.
Thankfully its not had in China. Most of the mark 4 series kobelco had a Cummins engine
 

deereresurrector

Active Member
Joined
Mar 11, 2017
Messages
28
Location
Crockett, TX
Occupation
technician
I have to know what engine & fuel system is in it before I can help..
MOST fuel systems have whats called a "torque back up".. that's what engaged when you reach the end of your stroke..
It increases the fuel and holds the governor to prevent the engine from shutting down.. under those momentary loads..
There is also a dump valve in the hydro system, that may not be working/set properly.. and unless you put gauges on the system, and take readings, your pizzing in the wind..
Ok pump guythe model # is CB.3-C cummins engine Family group xcexld505aba ,OD/L 505/8.3 , CPL 1845 , Serial # of engine 45821671, The injection pump is a Bosch tag on back of inj. pump is 96224 CDC ,0 402 066 702 AA , bar code on tag is 3933341 0100, plate on the side of injection pump is PFS6P?0A 120R3336-1, 0 402 066 702, 9612054175. If there is a governor issue what would be the adjustment spec? I really appreciate your feedback. thank you
 

deereresurrector

Active Member
Joined
Mar 11, 2017
Messages
28
Location
Crockett, TX
Occupation
technician
I wasn't aware that it's Cummins powered. All I have ever seen is Isuzu or Mitzi engines in them. Maybe it's been repowered. Most Jap excavators I have come across have a screen in the tank,screen in the banjo bolt going into the lift pump. I have also come across fuel hoses that have delaminated internaly mainly on older gear and can never be seen just by looking at the outside..All these thing I would be looking at before buying any parts.
The only I could find doing a real quick search on the engine is it's made in China. I maybe wwwrrrrooonnnggg.
The ycu 1127 sk300lc mark iv seems to be a rare model ,but by serial # the engine is correct to my knowledge
 

deereresurrector

Active Member
Joined
Mar 11, 2017
Messages
28
Location
Crockett, TX
Occupation
technician
It may not be a hydraulic problem. I suggest you first check the fuel system to insure the engine is producing proper power including the screen in the banjo fitting on the lift pump.
what component has this #/
I have to know what engine & fuel system is in it before I can help..
MOST fuel systems have whats called a "torque back up".. that's what engaged when you reach the end of your stroke..
It increases the fuel and holds the governor to prevent the engine from shutting down.. under those momentary loads..
There is also a dump valve in the hydro system, that may not be working/set properly.. and unless you put gauges on the system, and take readings, your pizzing in the wind..
What is a torque back up and how do I check or set it properly? This unit is about an hour away from me so I'm trying to get a days worth of checks and diagnostics before I return to location.
 

partsandservice

Senior Member
Joined
Feb 14, 2011
Messages
846
Location
Georgia
Simple test, if the engine blows black smoke as it stalls you have an air restriction of lost boost pressure, or to much torque load from hydraulic pump. if any one has monkeyed with or removed either torque controller on the pumps start there. No smoke on stall , fuel system issue. Low lift pressure from supply pump or faulty overflow valve. Check the engine smoke. Sounds like a hydraulic pump,issue from where I sit.
 

rmllarue91

Senior Member
Joined
Apr 16, 2014
Messages
701
Location
northeast pa
Occupation
field technician
Hey Deere did you inspect return filters
Many piston pumps run into issues not destroking from mechanical failure. If there is no metal found I'd check releif pressures. The control of pumps output volume hydraulicly and electronically are the most complex and time consuming so I save them for last. I have no experience with kobelco. Good luck
 

deereresurrector

Active Member
Joined
Mar 11, 2017
Messages
28
Location
Crockett, TX
Occupation
technician
Simple test, if the engine blows black smoke as it stalls you have an air restriction of lost boost pressure, or to much torque load from hydraulic pump. if any one has monkeyed with or removed either torque controller on the pumps start there. No smoke on stall , fuel system issue. Low lift pressure from supply pump or faulty overflow valve. Check the engine smoke. Sounds like a hydraulic pump,issue from where I sit.
Black smoke bellows out during stall. So as far as air restriction the intake pipe isn't losing its shape and turbo charger turbine is not sloppy. Educate me please
 

deereresurrector

Active Member
Joined
Mar 11, 2017
Messages
28
Location
Crockett, TX
Occupation
technician
Hey Deere did you inspect return filters
Many piston pumps run into issues not destroking from mechanical failure. If there is no metal found I'd check releif pressures. The control of pumps output volume hydraulicly and electronically are the most complex and time consuming so I save them for last. I have no experience with kobelco. Good luck
Return filters on hydraulic system? The two in the hyd res. Have been changed brand new .now where would the return filter be?
 

rmllarue91

Senior Member
Joined
Apr 16, 2014
Messages
701
Location
northeast pa
Occupation
field technician
The two large ones should be return if you still have them I'd cut them open and inspect for contamination.
 
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