Hi All,

I am new to the forum and a new forklift owner so forgive me if I use the wrong terms or wording.

I recently purchased a used crown FC-4000. The forklift works beautifully. The steering, drive motor, breaking, and mast all function as they should. The only issue I'm having is a strange noise that is coming from the engine compartment when the forklift is in park. Here is what the symptoms are:

I turn the forklift on and everything starts up and sounds completely normal. After about 20-30 seconds an unusually load humming/vibrating noise comes from underneath the foot plate. When I take it off the parking break the noise goes away and all sounds and works fine. As long as I am driving and using the forklift no noise is being made. When put back into park (about 10-20 seconds later) the noise comes back on.

I had a chance to read thought the service manual and I have a strong feeling it is something to do with the steer motor going into a low pressure state once the accumulator reaches a high enough pressure since I only hear the noise when the forklift is not being used and parking break is engaged.

The forklift is a 2007 with about 13,000 hours. There are no modifications or aftermarket parts on the forklift that I know of. Do you guys have any suggesting on what it may be? Or maybe have any other steps you would suggest to troubleshoot the forklift a bit more.

Any help is greatly appreciated!