Hello, curious about a problem with a no start engine.
I replaced the fuel injector pump in a 2009 skytrak mmv. I wasn't the original mechanic on this job. Anyway, I replaced it and it still will not start. I noticed that when I am cranking it over, the boom goes up on its own and it will not go back down.
I was thinking a hydraulic pressure lock on the motor do to a stuck open valve. I am asked to drain the hydraulic tank to see if the motor runs with no hydraulic pressure at all.
Any thoughts as to why the boom would raise by itself while cranking and having no start?
Showing items 1 - 3 of 3 results.
2 things
First, what is the serial number of the machine?
Second, you don't want to run it with no fluid in the hydraulic system , that will damage the pump and if it has a hydrostatic drive the same goes for that pump.
Check for voltage at the coils for lift valve, and ground.
Another way to disable hydraulic function is to disconnect the dump valve located under the joystick (at least the manual i looked at showed it located there.)
Hello, sir. I have disconnected the joystick and the lift solenoid. Still goes up on ignition. I checked the diodes and relays. I understand that the engine is under a load and will not start, but I have tried all of this. Currently I am removing all hydraulic fluid to see if the PTO will not push while starting. I do appreciate your comment and thoughts. No luck so far.
Yes if the machine is loading up the hydraulic system it can prevent the engine from starting because of the extra load preventing the motor from turning over freely.
i would check the joystick or switch that controls the boom, also if you can locate the solenoid manifold block controlling hydraulic functions and disconnect the boom lift solenoid to prevent it from raising the boom.
If you go to JLG website and look for their service literature they do have parts and service books available to the public for skytrack machines. You will need these to locate the components and test them.
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