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05 Caterpillar 277B Aux Hydraulic Malfunction

Iggys6

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Joined
Oct 10, 2016
Messages
66
Location
CT
Hi I have a 2005 cat 277b. Last time I used the aux hydraulics were about a month ago. I was using my grapple to move a few logs around. I just bought a new brush hog so I began to use it this morning, It worked for about 5 seconds and then stopped, I tried to go the other way on the thumb and the same thing happened. Now when I try again nothing happens, I tried to press the continuous flow button below the horn button and do not hear any relays. So far I am at the point to where I hooked the grapple back up and now it moves it just a little and then completely stops, I have to turn off and turn back on the machine to get it to move a little again. So now I have a grapple that will not even work and I am assuming my continuous flow is not working. I am hoping someone on here could help with this issue. Thanks in advance
 

DIYDAVE

Senior Member
Joined
Feb 18, 2007
Messages
2,409
Location
MD
First thing I'd check is the couplers, to make sure they are both seated. Then move on to the solenoid that activates the AF...
 

Iggys6

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Joined
Oct 10, 2016
Messages
66
Location
CT
First thing I'd check is the couplers, to make sure they are both seated. Then move on to the solenoid that activates the AF...
Both couplers are seated. What solenoid activates the AF? I checked the closest one near the right joy stick under the cab and I get 1.8-2ohms testing it which I believe is good
 

Mark250

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Joined
Aug 30, 2015
Messages
1,243
Location
victoria,Australia
Occupation
heavy equipment technician
hi Iggys6 this is the same machine you had water ingress to the ECMs. is it possible you still have issues in this area .why I say this is because the aux hydraulic ECM controls the A1 and A2 flow to your Aux Hydraulics .
As Above I would also recheck your couplers. your brush hog may have had crap in the lines which has now got into your machine
Mark
 

Iggys6

Well-Known Member
Joined
Oct 10, 2016
Messages
66
Location
CT
hi Iggys6 this is the same machine you had water ingress to the ECMs. is it possible you still have issues in this area .why I say this is because the aux hydraulic ECM controls the A1 and A2 flow to your Aux Hydraulics .
As Above I would also recheck your couplers. your brush hog may have had crap in the lines which has now got into your machine
Mark
Yes correct. Sadly this machine has been a nightmare. I pulled apart the aux ecu just now and there was some oil somehow in where the connector plugs into the aux ecu so I cleaned out everything and split the ecu and cleaned that out also. now it is back together and I still have the same problems. I hooked up to my grapple and it still only moves very little and then stops almost like a safety valve is kicking in. I checked the connectors and they seem like they are working as the grapple was nice and easy to hook up. Any chance there is a problem with a solenoid? Also I still press the button under the horn for constant flow and I do not hear that relay clicking. Thanks
 

Iggys6

Well-Known Member
Joined
Oct 10, 2016
Messages
66
Location
CT
Also I checked the resistance from the button under the horn to make sure it is working and it is I get approx 2 ohms
 

Iggys6

Well-Known Member
Joined
Oct 10, 2016
Messages
66
Location
CT
What resistance should the aux hydraulic solenoids have when I test them. A1 and A2?
 

Iggys6

Well-Known Member
Joined
Oct 10, 2016
Messages
66
Location
CT
2.2ohms +/- .2 ohms
Ok yea that is what I am getting for them. What else should I check? I just replaced the right joy stick a couple months ago so I think I'm ruling that out for the aux hydraulic fault
 
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