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Bobcat T190

Johnny5590

Member
Joined
Mar 25, 2020
Messages
7
Location
Scotch Plains NJ
I’m having problems with my power bob-tach. It suddenly stopped working. Before going further I simply changed the wedge up/down switch. Nothing
Does anyone know where I should go from here?
Thanks
 

Txhayseed

Senior Member
Joined
Dec 23, 2019
Messages
610
Location
Texas
So you changed the swith and it stopted working or it stop working then you changed the switch ?
 

Johnny5590

Member
Joined
Mar 25, 2020
Messages
7
Location
Scotch Plains NJ
Good morning
I changed the switch after it stopped working. But I did not check for power at the switch until after I changed the switch. Yesterday I checked for power at the switch and found none. I checked all fuses but not the relays in the fuse box.
 

Johnny5590

Member
Joined
Mar 25, 2020
Messages
7
Location
Scotch Plains NJ
Today I jumped power to the switch. Bobtach now opens from the switch but will not close from the switch.
it closes when I tilt the bucket hydraulics back to the extreme position.
What does this situation mean?
Has anyone else out there had a similar problem?
 

Mbar

Senior Member
Joined
Dec 15, 2018
Messages
263
Location
North Carolina
Sounds like low charge pressure or the coil not opening the spool far enough and having to dead head the system to make enough pressure
 

63 caveman

Senior Member
Joined
Nov 11, 2017
Messages
340
Location
western Pa.
Possibly the nut holding the solenoids on the bobtach valve block is loose or missing so not pulling spool out all the way (solenoids just floating on shaft). The valve block on that machine is behind the hydraulic pump (I think) and no fun to get to.
Good luck and let us know what you find out.
 

Johnny5590

Member
Joined
Mar 25, 2020
Messages
7
Location
Scotch Plains NJ
Sounds like low charge pressure or the coil not opening the spool far enough and having to dead head the system to make enough pressure

Thank you!
When I jumped power to the switch the bobtach opens so I would think that the coil works. Right?
I'm trying to trace the wires from the switch back to the coil to see if there is a break somewhere
 

Johnny5590

Member
Joined
Mar 25, 2020
Messages
7
Location
Scotch Plains NJ
Possibly the nut holding the solenoids on the bobtach valve block is loose or missing so not pulling spool out all the way (solenoids just floating on shaft). The valve block on that machine is behind the hydraulic pump (I think) and no fun to get to.
Good luck and let us know what you find out.
Thank you caveman
I'm having difficulty locating the valve block. You are correct, it's not fun to get to.

Question: if the bobtach levers open when I jumped power at the switch, can the coil still be bad or would you assume that I have a bad electrical connection?
 

63 caveman

Senior Member
Joined
Nov 11, 2017
Messages
340
Location
western Pa.
when you "jump power" you maybe jumping it to the the output pin to just one of the solenoids (open)on the bobtach valve.

The first thing is to determine is if you have an electrical or hydraulic problem? Since you haven't stated any other problems other than the power bobtach I guess the charge pressure is OK.

Did you check to see if you have power (12vdc) coming into the switch (pin 2), use a test light if you have one and if so, can you toggle it to the two out put pins 1 and 3 with the switch?
 

Johnny5590

Member
Joined
Mar 25, 2020
Messages
7
Location
Scotch Plains NJ
when you "jump power" you maybe jumping it to the the output pin to just one of the solenoids (open)on the bobtach valve.

The first thing is to determine is if you have an electrical or hydraulic problem? Since you haven't stated any other problems other than the power bobtach I guess the charge pressure is OK.

Did you check to see if you have power (12vdc) coming into the switch (pin 2), use a test light if you have one and if so, can you toggle it to the two out put pins 1 and 3 with the switch?

Hi caveman
I did confirm with a test light that there is no power on the switch located on the console.
So, with the test light I checked for a power supply from one of the spare auxiliary sockets behind the upper console next to the switch.
That is where I jumped a temporary wire to the switch so I could open the bobtach in order to change my bucket. The power bobtach opened withe temp power. After attaching my bucket I removed the temp wire because I was fearful of back feeding the circuit and possibly damaging something else.
To me, it seems like this in an electrical problem. Maybe a broken power wire feeding the switch?
 

Mbar

Senior Member
Joined
Dec 15, 2018
Messages
263
Location
North Carolina
You can google s250 service manual and get a wiring schematic for your machine. The 250 and 190 are the same harness. I’m guessing yours is a g series
 
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