Rough start-up for RFM

[wushaw]

I had a different brand RFM that was smooth and vibration free at any rpm setting from idel to mowin speed.
I thing you have something out of ballance or what has been said about a bad spindel. I ran this mower behind a tractor that had 15hp at the pto.

 

[Fishguy]

I "assume" you filled the gearbox with oil lubed all the spindles first, right? /forums/images/graemlins/blush.gif I recently bought one from TSC as well (6') and they are not serviced.
Also, remove the belt cover and see if the owners manual is under there. Don't know why they put them there, but mine was trashed by rain and the initial run up. Sure made a wierd noise. /forums/images/graemlins/wink.gif
Luckily I had printed on off their web site prior and found what needed to be done before use.

Good luck!
Steve

 

[RickS]

Yes, I filled the gearbox and found the manual, albeit by accident. Strange place to put it. /forums/images/graemlins/tongue.gif I greased everything, but I'll check closer this evening. Thanks for the replies.

 

[KiotiJohn]

Best to start your mower barely lifted, not too high, or not lifted at all but sitting on the wheels. Safety first. If the blades were loose or there was something caught up underneath, you'd stand a better chance of not doing any damage with the mower down low.

The first thing that I thought of was, is the PTO shaft hitting/rubbing on something since you have the mower lifted. If the shaft wasn't cut just right, it could bind on lifting. Make sure you check where it's positioned when fully raised.
John

 

[George2615]

I just bought the 5' KK rotary cutter (2 blade). Assembled it, filled gearbox, greased u-joints, then hooked it up and took it out to the driveway to test run. I engaged it at a low RPM (owners manual says to engage at idle) and it seemed to be off balance (quite a bit of vibration). Stopped the tractor and checked underneath for any looseness or a bent blade or something but found nothing bad or bent. Blades have about 3/8 - 1/2" play lifting up on the end of the blade. Blade mount bolts are tight. They have to be free to pivot if you hit something solid just seems to me like more up /down play than I'd like to see. Vibration eased up a little at 540 RPM. Maybe I'm just not used to the shaking. Those 2 blades have a lot of weight to spin around. Maybe they aren't balanced blades?

 

[KiotiJohn]

</font><font color="blue" class="small">( They have to be free to pivot if you hit something solid just seems to me like more up /down play than I'd like to see. Vibration eased up a little at 540 RPM. Maybe I'm just not used to the shaking. Those 2 blades have a lot of weight to spin around. Maybe they aren't balanced blades? )</font>
I don't have a lot of up/down play in my RC, but I want to suggest that what happened may be that one of your blades didn't spin out as fast as the other, getting the vibration started and then the other kicked out, but the vibration already had its momentum.

When that happens, try lowering the RPM back down and letting it settle a bit and then run it back up, or disengage the PTO and let it spin down and restart it at low idle again.

I've had it happen several times on mine after some materials got wrapped around one blade making it start the throw out a little later than the other blade. One that has sat outside at the store for a while may just have had enough rust to cause the same problem. Spray the mounting side of each blade with Lithium delayed viscosity grease and it should help.
John

 

[gator]

</font><font color="blue" class="small">( Roger that, Ken. I engage it while raised on the 3pt hitch. )</font>

Rick did you check the PTO length to make sure its not to long and bound up when you start it with the 3PH up? Just a thought.

 

[H3hound]

I just got the 72" 3 spindle KK finish mower. I do not engage in the raised position and start at or just below 1000RPM. Mine spins up smoothly. Also, I did not have to cut the PTO shaft to fit.

I would check for free movement in all the moving parts, make sure the blades are on correctly - one could be upsidedown, and recheck the PTO connections - shear bolt, PTO/tractor clip, PTO size.

Good luck.

 

[john_bud]

Rick,

Do you put in the clutch when you engage the PTO and then slowly let out the clutch? The shock load from just flipping the switch will either wear out PTO clutches (if you have them) or snap something inside the tractor making loud expensive sounds.

Also, does it have a shear bolt of slip clutch on the PTO driveline? If it has a slip clutch, you need to loosen it up, allow it to slip, then tighten it back down to specs. Slip clutches have a tendency to rust up and not slip making that expensive noise when a large rock, stump or what not is pinned by a blade.

luck!

jb

 

[RickS]

</font><font color="blue" class="small">( Rick,

Do you put in the clutch when you engage the PTO and then slowly let out the clutch? The shock load from just flipping the switch will either wear out PTO clutches (if you have them) or snap something inside the tractor making loud expensive sounds.

Also, does it have a shear bolt of slip clutch on the PTO driveline? If it has a slip clutch, you need to loosen it up, allow it to slip, then tighten it back down to specs. Slip clutches have a tendency to rust up and not slip making that expensive noise when a large rock, stump or what not is pinned by a blade.

luck!

jb )</font>

jb, my 4010 does not have a clutch, just a PTO on/off knob. It is full hydrostatic. With my tiller it sort of "soft starts". I can engage the PTO at idle with no problem. I will look closer at the mower soon. Just not enough time in the day.

The mower came with shear bolt. I would like to get a slip clutch for it, but I'm actually considering selling the whole thing and getting a riding mower, so I'll hold off for now. I don't really need the tractor now that I've done my tilling and dirt work. We'll see. Thanks for the reply.