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Hitacha EX120 fuel problems

Benco

Member
Joined
Sep 15, 2019
Messages
18
Location
Eastern shore MD
Occupation
Owner/Operator
Hi guys I have a 1999 hitacha EX120 with 1700 hours. It was running great when i parked it in my shop last May 2018. Well yesterday i went to start it an it just turned over wouldn't start. But it would run with eather. so i cleaned tank put all new fuel hoses on because I found a crack in one. I cleaned the banjo bolt filters, installed new fuel filter, put a new primer on the lift pump because when i would pump it a lil bit of fuel was coming out around the sides. Then i blead the fuel lines an primed it and Tried to start it again an she would try to start but she wouldn't. So i unscrewed one of the fuel lines on the injector pump that run to the injector to see how much fuel would come out while trying to start it and only a lil bit came out. I don't think she getting enough fuel.
Is there any way to tell if the lift pump is bad? I wouldn't think the injector pump would go bad from sitting for a year.
Oh I forgot! When I replaced the primer on the lift pump i lost the spring so i put a spring in it that was close to the same one it seems to work. I noticed my ex60 excavator has the same set up and when you prime it you can really feel that its priming and on the ex120 when ur priming it dosent get as tight.

Any Ideas? I appreciate it
 

BigWrench55

Senior Member
Joined
Oct 11, 2018
Messages
1,176
Location
Somewhere
Does your machine have a electric lift pump inside the door where the hydraulic pumps are?
If so I would check that and also there is a screen inside that pump. There also are screens in the banjo bolts on your fuel filter. Hope this helps.
 

Benco

Member
Joined
Sep 15, 2019
Messages
18
Location
Eastern shore MD
Occupation
Owner/Operator
Thanks..i checked all the banjo bolts and there is no electric pump. Im thinking the lift pump on the side of the injector pump is bad im catch hell takeing it off its in a tight spot but i got to start somewhere
Thank you again
 

thepumpguysc

Senior Member
Joined
Mar 18, 2010
Messages
7,585
Location
Sunny South Carolina
Occupation
Master Inj.Pump rebuilder
I don't think u can find an appropriate spring to replace the "hair" spring in the sp..
Also make sure the overflow valve is ok & the spring isn't broken.. or the plunger isn't stuck from sitting..
 

thepumpguysc

Senior Member
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Mar 18, 2010
Messages
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Sunny South Carolina
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Master Inj.Pump rebuilder
The ovflow is located on the return fuel side on the inj. pump.. THATS what holds the pressure in the fuel gallery on the inj. pump..
 

Benco

Member
Joined
Sep 15, 2019
Messages
18
Location
Eastern shore MD
Occupation
Owner/Operator
Are the overflow valves like banjo bolts with a spring and ball in them if so i checked them and they seem ok. When you pump the primer alot you can hear the fuel going in the tank
 

thepumpguysc

Senior Member
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Mar 18, 2010
Messages
7,585
Location
Sunny South Carolina
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Master Inj.Pump rebuilder
To tell if the sp is working.. take off or loosen the INLET LINE ON the INJ. PUMP.. use the HP or spin
the engine & see if anything squirts out of that loosened line going into the INJ. PUMP..
U SHOULD get wet.. {lotsa fuel}
 

thepumpguysc

Senior Member
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Mar 18, 2010
Messages
7,585
Location
Sunny South Carolina
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Master Inj.Pump rebuilder
Any chance of taking the sp off the 60 & swaping them.??
U HAVE TO hold them side x side to MAKE SURE the BACK SIDE has the SAME extension..
IF the 60 is LONGER than the 120.. it will SMASH the sp.. & if its shorter, u prob. wont get the correct stroke to move the fuel..
& make sure the hp is on the correct side..
 

thepumpguysc

Senior Member
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Mar 18, 2010
Messages
7,585
Location
Sunny South Carolina
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Master Inj.Pump rebuilder
The sp's are very easy to o/h.. Theres a plunger & spring under the big nut.. the spring breaking are VERY common..
& depending on your fuel "quality" the piston might be stuck or scored..
 

Benco

Member
Joined
Sep 15, 2019
Messages
18
Location
Eastern shore MD
Occupation
Owner/Operator
I'm omw to my shop now to check it out I will let you know the outcome thanks for you help
The sp's are very easy to o/h.. Theres a plunger & spring under the big nut.. the spring breaking are VERY common..
& depending on your fuel "quality" the piston might be stuck or scored..
 

Benco

Member
Joined
Sep 15, 2019
Messages
18
Location
Eastern shore MD
Occupation
Owner/Operator
I'm omw to my shop now to check it out I will let you know the outcome...
The lift pump was bad so i took took it off an ordered a new one. And it wasent that hard to take off. It took me longer to find the right wrinch then it did takeing the 3 bolts off..
Thanks for all your input it really helped
 
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