BL4690 Backhoe jerkiness

greeno

Member

Equipment
B2710 w/LA402 FEL, BL4690 hoe, RB1560, GS1560, Haban 5' sickle bar, 5' JD RC
Jul 14, 2018
187
2
18
Big Lake MN
The swing and boom functions on my backhoe are very fast; but the curl and crowd are very slow. Is there a way to address this? For sure I'd like to take some of the quick jerkiness out of the swing and boom.
 

jajiu

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Lifetime Member

Equipment
L3560 HSTC, Grader, Backhoe, Snow Plow, Pallet Forks
Jun 5, 2016
453
111
43
73
Rowley, Massachusetts
Try running at a lower engine RPM. It helped me and when you get better at it you can increase the RPMs.
 

TheOldHokie

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Equipment
L3901/LA525, B7200DT/B1630, G2160/RCK60, G2460/RCK60
Apr 6, 2021
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Myersville, MD
windyridgefarm.us
The swing and boom functions on my backhoe are very fast; but the curl and crowd are very slow. Is there a way to address this? For sure I'd like to take some of the quick jerkiness out of the swing and boom.
The physical geometry of the cylinders may have something to do with that.

Dan
 

Henro

Well-known member

Equipment
B2910, BX2200, KX41-2V mini Ex.
May 24, 2019
5,116
2,341
113
North of Pittsburgh PA
The swing and boom functions on my backhoe are very fast; but the curl and crowd are very slow. Is there a way to address this? For sure I'd like to take some of the quick jerkiness out of the swing and boom.
Is this something new? Did you buy the tractor/backhoe new or from another owner?

I have a B2910 with the same backhoe. For me, 1800 to 2000 engine RPM is the sweet spot. Faster equals jerky, and I have used the backhoe a lot over the years, so it is not beginner effect.

Bought an old mini ex a couple years ago, and so I have not been using the tractor backhoe. But I THINK the jerkiness I remember was in the boom swing.

Never found two motions fast, and two relatively slow though.

If you bought it from a third party, maybe for some reason they put flow restrictors in the lines for the functions that are moving slowly? How do cylinder diameters compare? A larger diameter cylinder will move slower for the same fluid flow.

Just a couple thoughts. Tell us more...
 

greeno

Member

Equipment
B2710 w/LA402 FEL, BL4690 hoe, RB1560, GS1560, Haban 5' sickle bar, 5' JD RC
Jul 14, 2018
187
2
18
Big Lake MN
I bought it used 5 years ago from a dealer and it’s always been that way. I blew the inlet hose and had to tear into the control tower so I thought I’d see if there was something I could do since I was in there.
 

Henro

Well-known member

Equipment
B2910, BX2200, KX41-2V mini Ex.
May 24, 2019
5,116
2,341
113
North of Pittsburgh PA
I bought it used 5 years ago from a dealer and it’s always been that way. I blew the inlet hose and had to tear into the control tower so I thought I’d see if there was something I could do since I was in there.
What engine RPM are you using when using the hoe? As I think I mentioned above at around 2000 mine is somewhat jerky. I usually use 1800 normally. Never felt that any of the functions were slow compared to others though...

As an aside, the old mini ex I bought is a bit loose, and at higher PRMs I also notice jerkyness so I run it at 2000 RPM or a bit lower as well...
 

greeno

Member

Equipment
B2710 w/LA402 FEL, BL4690 hoe, RB1560, GS1560, Haban 5' sickle bar, 5' JD RC
Jul 14, 2018
187
2
18
Big Lake MN
usually about 1800rpm.

i guess i should clarify; my biggest complaint is when booming or swiveling the cylinders move fast and come to an abrupt stop, which shakes the whole unit.
 

Dieseldonato

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Equipment
B7510 hydro, yanmar ym146, cub cadet 1450, 582,782
Mar 15, 2022
728
437
63
Pa
The machine isn't likely to be the issue, more so it's not doing anything wrong. Your letting off the valve too abruptly and there no soft stop feature built into little hoes. My old man's 3pt hoe is the same way with him operating it. I operate more equipment then him so have been able to figure out how to be easy on the swing transitions. Try easing up on the stick right before you want to stop, so it's not an all or nothing motion. Using 2 functions with a single (fixed displacment) pump set up will also slow the works down a good bit. It's the nature of the beast. Just something to get used to.
 
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mikester

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Equipment
M59 TLB
Oct 21, 2017
3,127
1,609
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Canada
www.divergentstuff.ca
Use it every day for 8 hours a day. After a few years you will either
1. become a smooth operator
2. break something

Only you can answer this question

Often going slower means getting it done faster.
 
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