I have an L4508 and run a PTO tiller and trencher. When I hit hard soil with either implement the PTO starts clacking loudly and the speed selection lever on the PTO jerks with every loud clack. I need to slow the engine speed to just above idle and run the PTO at 540 RPM to minimize this otherwise it is a constant noise. Can anyone describe what is going on and whether I need this in for service? The tractor has about 900 hours on it but the PTO has been used less than 50 hours because for many years I only had non-PTO implements.
PTO clacking
- Thread starter Maxx
- Start date
So we are not going to know much about your tractor specifically... BUT my tractor has "Overriding PTO" CAMs AND I wonder if you have the same??
You can see that kubota no longer use these, the PDF talks about replacing them with Locking Cams (see attach). What year did you get your tractor?
I sold a tiller because my PTO would skip with the tiller (not bad but enough) but I did not want to replace the CAMs to the new style ($1200 USD) might be more now...
So, you can quit using the PTO with high demanding pressure or talk to the dealer about a fix...
Little back ground, if you were mowing and pressed the clutch, would you hear the same "constant noise"??? Does it sound like it ratching (clicking quickly)?
PS. Welcome! to Orange Tractor Talks...
You can see that kubota no longer use these, the PDF talks about replacing them with Locking Cams (see attach). What year did you get your tractor?
I sold a tiller because my PTO would skip with the tiller (not bad but enough) but I did not want to replace the CAMs to the new style ($1200 USD) might be more now...
So, you can quit using the PTO with high demanding pressure or talk to the dealer about a fix...
Little back ground, if you were mowing and pressed the clutch, would you hear the same "constant noise"??? Does it sound like it ratching (clicking quickly)?
PS. Welcome! to Orange Tractor Talks...
rbargeron
Well-known member
Lifetime Member
Equipment
L5450, L48, L3250, L345 never enough attachments
Sounds serious but fixable - like broken gear teeth. Ground-engaging implements (tillers, rotary mowers, etc) can damage pto gears - teeth can break off and cause a knock every revolution - louder under load. Need to replace the damaged parts. Running it that way risks worse damage - to tractor and wallet. Once repaired, a slip clutch on the pto shaft will helps prevent it happening again (may protect the tiller too).
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I also have an earth auger with a 16" drill and that puts decent pressure on the PTO but at much lower RPMs and I don't hear any such noise when in use. Also if I engage the drive with the tiller raised so there is no pressure on the PTO, there is no noise as one might expect if there were teeth missing on any of the PTO gears. As for the noise itself, yes it is an irregular ratcheting sound with 1 or 2 pops then back to normal operation to 5-6 or 7 pops depending on the hardness of the soil but the noise comes and goes randomly. Once I get 3-4 passes and the soil has been broken up, I can run the tiller at 720 RPM, turn the engine speed to 1500, and till in 2nd gear and everything runs smoothly.
The tractor was purchased new in 2009 or 2010
When I engage the PTO with nothing attached or with the tiller raised, I don't hear anything that suggests broken teeth. In fact, the sounds are normal until the torque is challenged by hard soil. Not knowing much about the PTO I wondered if there was some safety mechanism that disengaged the drive momentarily when the pressure exceeded a certain limit. Based on my use, I think Old and Tired might be on to something so I plan to head to the Kubota shop and ask some questions. The trouble is, they don't speak English and I don't speak Thai and my wife, as the translater, doesn't know how to describe technical problems and doesn't know the comparable Thai words (if any even exist) in describing the problem. For example, when asking about tires and tubes, you just point and say "outside and inside" in Thai of course and everyone know what you are talking about. So my trip to the dealer will be really fun!
Also, thanks for the replies and the information. I now have a plan. Where can I find a diagram of a Kubota PTO so at least I can show what part of the tractor I am concerned about. I think I know where this is heading. Someone from the dealer will have to drive out and witness the sound himself. Fortunately here that only costs about $10.
I've read more about this and one guy described the L2800 with a transmission driven PTO with overriding cams which sounds like my L4508. The PTO is engaged by a lever selecting either 540 or 720 rpm. When I release the clutch the PTO engages at the same time forward motion begins and everything stops when the clutch is depressed.
I suspect the PTO Overriding PTO" CAMs are worn. I started using the PTO for the first time when I trenched for irrigation and drainage around my house. My soil is sandy and clay mix but there are places where the clay is very hard, dry, and packed. To get a one-pass trench I revved the engine to 2000-2200 and in low gear and 540 RPM on the PTO I attempted to cut a trench 7" wide by 24" deep trench and sometimes in hard soil I first noticed the clacking sound. But I needed to get my work done so I pressed on. I suspect I was pushing my little 4508 too hard which caused excessive wear. Unfortunately, I still have some trenching to do and with the tropical climate here everything grows so fast I need the tiller for weed control. I guess a trip to the Kubota dealer is in order and I hope the cost isn't too much. Labor rates are certainly cheaper here. The average wage is about $500-$600 a month and that is from a good job. Retail jobs pay $300 a month. I hire farmworkers for digging etc around the house and pay between $12 and $15 a day and I am a BIG payor! Anyway, thanks for the advice. I'll report back when I know more.
I've read more about this and one guy described the L2800 with a transmission driven PTO with overriding cams which sounds like my L4508. The PTO is engaged by a lever selecting either 540 or 720 rpm. When I release the clutch the PTO engages at the same time forward motion begins and everything stops when the clutch is depressed.
I suspect the PTO Overriding PTO" CAMs are worn. I started using the PTO for the first time when I trenched for irrigation and drainage around my house. My soil is sandy and clay mix but there are places where the clay is very hard, dry, and packed. To get a one-pass trench I revved the engine to 2000-2200 and in low gear and 540 RPM on the PTO I attempted to cut a trench 7" wide by 24" deep trench and sometimes in hard soil I first noticed the clacking sound. But I needed to get my work done so I pressed on. I suspect I was pushing my little 4508 too hard which caused excessive wear. Unfortunately, I still have some trenching to do and with the tropical climate here everything grows so fast I need the tiller for weed control. I guess a trip to the Kubota dealer is in order and I hope the cost isn't too much. Labor rates are certainly cheaper here. The average wage is about $500-$600 a month and that is from a good job. Retail jobs pay $300 a month. I hire farmworkers for digging etc around the house and pay between $12 and $15 a day and I am a BIG payor! Anyway, thanks for the advice. I'll report back when I know more.
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kubotafreak
Well-known member
Equipment
GRAND l6060, L3560, B6100, gr2100, tg 1860, g1800, g1900, g2160
It does sound like skipping in my overriding cams; only once in a while. I knew it wasn't good and I followed several threads back in 2005-6 where others with my setup continued using their tillers to the point where the PTO just got so worn out that it didn't work any more. Granted, they were a business and most likely used them harder than mine.
Also, once the soil was broken, you could till more without any problems... Good Luck
Also, once the soil was broken, you could till more without any problems... Good Luck
Russell King
Well-known member
Lifetime Member
Equipment
L185F, Modern Ag Competitor 4’ shredder, Rhino tiller, rear dirt scoop
For translating you can use smartphones now. I know that the iPhone has an app that can speak in languages that you select after you talk or type into the phone
Thanks. I'm moving ahead with the idea of overriding cams in the PTO to see where that leads.
I'm not sure what that means really. If by 'clutch' you mean the one in the main drivetrain..I can only say the movement of the tractor remains constant and steady but I do feel a sudden hit to the PTO engagement lever ...a jerking movement...ever time I hear the clacking sound while the PTO is engaged and the tiller is doing work. In other words, the tractor itself exhibits no pause or jerk that I can notice. When I raise the tiller up out of the soil so the tines are free-spinning, also there is no noise and no sudden jerking of the PTO engagement lever.
Yup, I use that at the home improvement store almost every time I go shopping. It's pretty close but you see there isn't a Thai work for every English word so things do get lost in translation. So a cotter pin in the US is a split pin here. A lock washer in the US is a split ring or split washer here. But a picture here is truly worth 1000 words! Thanks
ehenry
Active member
Equipment
BX22, FEL, BH, 40" pto tiller, 42" Bushog Squealer, pto hole digger, B7300 w/60"
Maxx, I've had something similar happen with my tiller and BX22. My problem turned out the be my top link pins were worn and the pin hole on my tiller had become somewhat egg shape. New pins and making the top link hole on the tiller round again fixed my issue. It didn't break the bank either.
I didn't see anyone mention this.
I didn't see anyone mention this.
Thanks, I'll check the top pin. My PTO use is less than 30 working hours so I'd think the top pin should last longer than that but since no one mentioned it before it is certainly worth a look. Also I'll look at other attachment points as well. Thanks
He's asking do you have this type of slip clutch, it's between the pto shaft and the gear box of the tiller (normally). All external to the tractor... it's on the implement side of life...
I don't have one but that is a good idea. I'll see if I can find one here. thanks.He's asking do you have this type of slip clutch, it's between the pto shaft and the gear box of the tiller (normally). All external to the tractor... it's on the implement side of life...
View attachment 52218
Also, I have looked but cannot find a schematic of the PTO showing these cams. Can anyone point me in the right direction? It might help me when talking to the Kubota service rep. Since I don't speak or understand Thai (well I can ask for a large beer, the check, and where the bathroom is), I don't know when they 'get it' or don't so I'd like to just point to the cams and then ask how much.
kubotafreak
Well-known member
Equipment
GRAND l6060, L3560, B6100, gr2100, tg 1860, g1800, g1900, g2160
Maxx,
I was asking because of the different driveline protections available. The ratchet type, will make sound you describe. The one with the external springs tend to be quieter since they have a brake lining. Either way something is probably not right. If you post a picture of your setup (whole three point-pto driveline) someone might be able to better answer, since we will understand what driveline your using.
I was asking because of the different driveline protections available. The ratchet type, will make sound you describe. The one with the external springs tend to be quieter since they have a brake lining. Either way something is probably not right. If you post a picture of your setup (whole three point-pto driveline) someone might be able to better answer, since we will understand what driveline your using.