Hydro Noise

JSlezak83 · #1 02-02-2021, 02:40 PM

I just finished cleaning up all the slop from a snow storm that changed to rain. The 1440 and 451 didn’t disappoint....well except for another nearly dead battery after running. I think the Briggs rectifier regulator is toast. Need to get out a DVM.

Anyhow, the issue at hand here is a hydro noise that’s coming from the tractor in reverse only. It’s not the typical whine, but rather an almost grinding sound. It’s almost like the normal whine is being amplified through the driveline. You can feel a vibration in the frame. This only happens in reverse, and slight pressure on the brake pedal will stop it. There seems to be a sticking in the pedal too, so I’m sure they are probably related. When you release the parking brake, you have to slightly lift the pedal.

This has been steadily getting worse over the last year or so. The control lever seems to be properly adjusted, as it holds neutral. I did fluid and filter a few weeks ago, and that didn’t help any. Is there a trunnion issue like the older models? I don’t want to cause any more damage by continuing to run it.

Ambush · #2 02-02-2021, 03:09 PM

It could be your pump port plate. Oil release slots and/or holes at the end of the work rotation may be obstructed or gouged. The pressure can’t release so it actually lifts the plate off the head to escape. The pitch should change with rpm and load. Should be quiet under no load

darkminion_17 · #3 02-02-2021, 05:49 PM

Leaving the release valve lever on will make it do that also, check and see if it is completely disengaged. You may want to lube up the brake lever assembly so it does not stick.

Ambush · #4 02-02-2021, 06:18 PM

Could also be the poppet on the relief valve.
Start with the easy stuff first.

olds45512 · #5 02-02-2021, 09:23 PM

Are you sure it's not the brakes? My 1440 makes noise in reverse and i figured out it was the brake pads dragging on the rotors.

JSlezak83 · #6 02-03-2021, 01:22 PM

I’ll have to get the heat running in the shed and pull the tunnel cover. I’ll see if I can’t post a video of the sound. You guys have given me a few places to start looking. I don’t think it’s the brakes dragging because it doesn’t change with wheel speed. It does seem to be more aggressive with RPM and it definitely does with load.

dale c. · #7 02-03-2021, 06:22 PM

make sure the axle mounting bolts are all tight

JSlezak83 · #8 02-10-2021, 07:00 PM

Quote:

Originally Posted by dale c.

make sure the axle mounting bolts are all tight

I don’t know if it was too late, I had one too many, or I read it too fast, but I dismissed this. I assumed you meant wheel lugs.

I pulled the tunnel cover off and gave the pivot points a coat of silicone spray. Somehow while doing this I pushed the tractor fore and aft, and it was immediately clear. The forward axle mounts were loose, causing the axle to roll, changing the pinion angle. The hydro noise in the driveline was the binding of the driveshaft. The explains the low wheel speed I was experiencing in reverse. The screws needed at least a full turn each side to tighten.

In the spring I will pull the wheels and do a little better job of tightening. Is there any merit in adding the SGT torque arms? Seems like that would be the time to do it.

JSlezak83 · #9 02-10-2021, 07:08 PM

You can see here where the driveshaft was wearing on the brake controls. Tapping the brake pedal moved the controls enough to stop the grinding noise.

Sam Mac · #10 02-11-2021, 08:33 AM

I'd be taking a good look at the mounting bolts for the rear end it looks like the rear has tipped forward allowing the drive shaft to contact the arm for the brake switch. This is what you should have for clearance in the pic.

The 1440 is a GT not an SGT so yes the GT rear end braces are a good idea.