T770 D7528 right swash plate out of position. Anyone familiar with this?
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Right now working with this problem...D7528... It started last summer with error of the solenoid. I changed it and during cold winter time it worked quite fine, no problems. Until last week..i changed left and right solenoids to find out if solenoid has some error but no, now the engine stops and D7528 shows up. Seem' s that i will be aqquinted with "swash plate" ...
If the weather is not warm there are no errors at all! The swash plate and the oil (HVLP 46) temperature- where is the connection ? Anyway, i tried the easy way- we just regulated the position of the swash plate using two buttons located on the top of the left joystick. If something else will rise up i let you know.
T550 :
what did you find out to fix the problem ?
TLJohnson99
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Hope you are still active and you found a fix, I have a machine doing the same thing now. I really don't think pulling motor with pump is the answer. Any tips or tricks would be awesome.
Ok, i`ll try to describe the protsess a little. First is reasnoable to find out if the solenoid has a problem There you can find 4 of them. Right side- 2 pc and left side two. They are located under cabine close to engine, there you can see this big pump unit with steering block`s, right and left side. Top of those blocks you ćan see solenoids, forward is looking forward, reverse is looking back. To find out if solenid has a problem is reasnoable to change two solenoids. I changed right side and left side. If the problem now goes from one side to another you can be shore that this solenoid has a problem and needs to be changed. If the problem stays there where it was than it`s reasnoable to try to calibrate the swash plate via maschines computer. It`s quite easy and usually people can do it . Just take your time. Better contact to your mechanic 
. This calibration you must do anyway if you changed the solenoid.
. This calibration you must do anyway if you changed the solenoid.I pulled engine and replaced the sensor and i still have the same problem.
"..pulled engine..." - what you mean with that? If you have a error code D7528 ... or D7527, you should find out if the sensor have a problem. Just read my post above, there is nothing more i can add. If it`s too difficult to manage just contact to mechanic.
jasoncouch01
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Great information. Thank you!Ok, i`ll try to describe the protsess a little. First is reasnoable to find out if the solenoid has a problem There you can find 4 of them. Right side- 2 pc and left side two. They are located under cabine close to engine, there you can see this big pump unit with steering block`s, right and left side. Top of those blocks you ćan see solenoids, forward is looking forward, reverse is looking back. To find out if solenid has a problem is reasnoable to change two solenoids. I changed right side and left side. If the problem now goes from one side to another you can be shore that this solenoid has a problem and needs to be changed. If the problem stays there where it was than it`s reasnoable to try to calibrate the swash plate via maschines computer. It`s quite easy and usually people can do it . Just take your time. Better contact to your mechanic
Can u recalibrate with just the machines computer or do a need an external plug in Bobcat type of thing?
Yes, you can calibrate it with machines computer. No additional equipment needed.
fortworth-cowboy
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DO NOT change the Swash Plate Sensor! These are NEVER the issue. It is possible that the Harness to The Hydrostatic Pump is rubbed through somewhere but these Sensor are never bad. The only time I had to replace those in 10 Years working by Bobcat, was when there was a other Problem and they got damaged externally.
Do you have your Serial #?
And can you check the color of the Hydrostatic Pump? I am pretty sure it is blue. But please check.
I pretty certain that it is the plastic bushings inside the pump mounted to the swash plates. These get loose and come out of the swash plates, when this happens the sensors are not getting the correct position anymore from the swash plates. The computer compares where the servos (on top of the Hydrostatic pumps) are and what the swash plate sensor report back. If this does not match the computer is shutting down the drive.
Do you have your Serial #?
And can you check the color of the Hydrostatic Pump? I am pretty sure it is blue. But please check.
I pretty certain that it is the plastic bushings inside the pump mounted to the swash plates. These get loose and come out of the swash plates, when this happens the sensors are not getting the correct position anymore from the swash plates. The computer compares where the servos (on top of the Hydrostatic pumps) are and what the swash plate sensor report back. If this does not match the computer is shutting down the drive.
"I pretty certain that it is the plastic bushings inside the pump mounted to the swash plates. These get loose and come out of the swash plates, when this happens the sensors are not getting the correct position anymore from the swash plates."
First you need to make sure that the solenoids are OK. Then you need to make sure that calibration is possible. If calibration is no longer possible, then you need to look for the problem elsewhere. Usually calibration is enough. Or replacing the solenoid.
First you need to make sure that the solenoids are OK. Then you need to make sure that calibration is possible. If calibration is no longer possible, then you need to look for the problem elsewhere. Usually calibration is enough. Or replacing the solenoid.
fortworth-cowboy
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Calibration is never possible if you have a active Drive Code. Solenoids throwing codes or you can swap them, but still very rare compare to the bushings. Specially when he complains that it gets worse when its getting hot.
BTW if its a Blue Hydrostatic Pump, they are known for having these kind of issues with the Bushings. The new Bushings are different plastic and stronger. Did usually so around 50 a year
fortworth-cowboy
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I am not saying that it could be NOT the solenoids, but I would swap them first around and see if the code changes before I throw money at it.
But to be honest, it can't be the solenoids: It could be the stems but not the solenoid. If the solenoids are bad they throw a code by themself. Like open circuit or short, etc. Swashplate codes are created when the swashplate sensor is register something different then what the computer commanded. So I would swap the solenoids (left and right or front and back) best would to swap them left to right. If code D7527 comes up is something with the solenoids. If it stays on D7528 it could be in the stems. You could swap them too and test it again.
How I said because of the machine and what pump is in there, I am pretty sure it the bushings. If there is NO damage to the pump harness.
What is the serial? I bet it starts with AT6.
