L3700 PTO Noise - Normal?

[e30racer]

I'm new to this forum and this is my first post. I just purchased my first tractor two weeks ago, an L3700 SU with FEL, Box blade, and 60' Land Pride rotary mower. I've noticed that when I engage the PTO at idle RPM (800) and completly let off the clutch that something starts making a fairly loud rattling/knocking noise. The noise sounds like it is coming directly below the drivers seat. Once I increase RPM to 1500 or so the rattle/knock completely smooths out and disappears. Is this normal or should I take the machine back to my dealer to have it looked at? Thanks for any info you can provide.

Steven

 

[leonz]

OH boy lots of opinions on this one:

I'm new to this forum and this is my first post. I just purchased my first tractor two weeks ago, an L3700 SU with FEL, Box blade, and 60' Land Pride rotary mower. I've noticed that when I engage the PTO at idle RPM (800) and completly let off the clutch that something starts making a fairly loud rattling/knocking noise. The noise sounds like it is coming directly below the drivers seat. Once I increase RPM to 1500 or so the rattle/knock completely smooths out and disappears. Is this normal or should I take the machine back to my dealer to have it looked at? Thanks for any info you can provide.

Steven

Don't start the PTO at low idle and it will not be an issue as the motor and drive train are loaded up with more demand due to engaging the Power Take Off at low idle.

You should engage the PTO at the PTO marking for that engine speed on the tachometer, and leave the throttle at that setting when running the implement.

 

[TripleR]

I never engage the PTO at "low idle", depending on the tractor 1500 or a little faster. It should be in your Operator Manual.

At a slow idle, you are going to get a lot of feedback until you spool up and the blades stop flapping around and settle into their extended position.

 

[montelatici]

It could simply be the chain that keeps the plastic shield from turning flapping around. According to the manual (and just normal good sense) you should not engage the PTO at high (540 PTO speed) RPM.

 

[Code54]

I have the L3700 also and often start my PTO at well below the 540 marking without any noise or clunking. Tonight I was starting the post hole digger at right about idle without any problems or noises. This also sounds odd to me and may be worth more inspection.
Good luck

 

[johnrex62]

I keep hearing people saying they are nervous about the high engine rpms on the Kubotas, but I am new to tractors and don't have the background with the older equipment to be aware of the "standard" rpm for a tractor.

I normally consider 1500 rpm to be about as low as I go on starting the tractor or engaging the PTO. It sounds fine to me and I have not noticed any PTO noise other than the blades on the cutter spinning up. My manual says to engage the PTO at a middle rpm, but sometimes I forget and engage at full 540 speed (2500 engine rpm). I can tell the diff on the blade spin-up sounds, but either way still sounds okay to me.

 

[rjkobbeman]

I always engage my PTO at idle RPM (around 800 I think). I simply feather the PTO lever until everything is turning, then engage it fully. The engine never skips a beat.

I think this is easier on everything involved. Engaging the PTO at a higher RPM (1500 or so) may not be a big deal, but I can't imagine engaging it at the "PTO speed" as suggested above. This seems like it would be very hard on the PTO clutch pack.

As long as you have a "good touch" with your PTO lever, you shouldn't load down the engine at all. Trust me, I am very much "in touch" with my tractor and would change my tune if I thought the engine was being loaded down and/or things didn't sound right.

 

[e30racer]

The owners manual says to "Engage the PTO at reduced engine speed to avoid shock loads to the PTO". It does not define what "reduced" is so the wording definitely leaves some room for interpretation.

BTW, I know the noise is not coming from my rotary mower blades or gear box. The noise definitely emanates from below the drivers seat somewhere in the driveline.

Could anyone with a later model L3400 or L3700 that either does or has engaged their PTO at idle speed tell me if they get the same clatter/rattle/knock that smoothes out at RPM's increase?

thanks,
Steven

 

[k0ua]

L3400, I engage at around 1000 to 1200 or so usually, above idle speed, but no where near the PTO 540 mark. have never heard any unusual noises.. if you do, I would have it looked at. If your cutter or other rotary implement is off of the tractor and you engage the PTO does it still make the noise?
James K0UA

 

[TripleR]

I always engage my PTO at idle RPM (around 800 I think). I simply feather the PTO lever until everything is turning, then engage it fully. The engine never skips a beat.

I think this is easier on everything involved. Engaging the PTO at a higher RPM (1500 or so) may not be a big deal, but I can't imagine engaging it at the "PTO speed" as suggested above. This seems like it would be very hard on the PTO clutch pack.

As long as you have a "good touch" with your PTO lever, you shouldn't load down the engine at all. Trust me, I am very much "in touch" with my tractor and would change my tune if I thought the engine was being loaded down and/or things didn't sound right.

When I tried running my Woods DS1260 with the M8540 at idle, my engine blew black smoke and bogged down before recovering. Mine works fine at about 1250. Now if I ever run it with my Land Pride 6', it will be a different situation. My L5030 needs a about 1250 or better for the LP. I just use what gets a smooth start with the tractor/equipment being offered. I have gotten to the point I usually don't even look at the tach any more.