Mid-Mount Mower I may be taking a gamble on a mower deck

[/pine]

I may be buying (sight onseen) a used mower deck that I am not even positive will fit my tractor...but that is not currently the issue...

I do not know the model # of the deck...All I know is it came off a Kubota B7100...

Can anyone tell me where I can by aftermarket parts that will fit? I'm looking for casters, blades , bearings etc...

can someone tell me where to look for a model # on the #...it has been painted grey...

 

[beenthere]

slashpine
You are a brave man.

 

[/pine]

Here's what I know...

It is missing the castors and blades but other than than it is supposed to be in working order...

It was originally under Kubota B7100...which is not very much different than my B1700... general size and HP are very close...so I am assuming I can "make it fit"...

oh by the way...the asking price is $150.00 obo

 

[whistlepig]

Most decks have a metal plaque on them with a serial number and model number. It may have been painted over. As far as after market parts blades shouldn't be a problem. The castors may be hard to find other than a dealer.

 

[Leejohn]

The b7100 had the RC54-71B and RC60-71B mowers and it said only with HST ser.#61077 and up. Also not compatible with the B1630 loader. For the price I would make it fit.

 

[easygo]

I think finding the casters, blades and especially the bearings would be the easier part. What might be your worry is that the attachment points on the two tractors could be slightly or not so slightly different. You may be looking at cutting two to six tabs off the deck and re-weld them in the proper position and even have to modify some of the linkage that attaches it to the tractor. Call dealers and see if any of them have information on the interchangeability of the decks. You know what machine it came from and what you want to attach it to. It should not be very hard for the dealer to find out. However. $150 sounds like a price that is worth the gamble.

 

[/pine]

[update]

OK...I took the gamble and bought the deck for $150.00

The general shape of the deck is decent...some medium pitted areas along the drain channels and spindle recesses...but it is still VERY solid...

What is missing are the arms that span either side of the deck and hold the wheels/casters...I will either need both (L,R) entire assemblies or I will have to improvise with whatever I can salvage from another deck etc...

The gear box and yoke shaft/u-joint are like new...the spindles/bearings are in good shape although I will be replacing the seals...

As mentioned This particular model RC60-71b was not built to fit my B1700...I am in the process of comparing a model that will fit the B1700 to the deck I have...modifying the mounting brackets should not be a problem if required...

However...I am concerned about the RPMs and the gear box ratio...my front PTO turns at 2500 RPM and the gear box seems to be a little better than 1/1...something like 1/1.125 maybe?

What is the ideal RPM of mower blades?

 

[aczlan]

However...I am concerned about the RPMs and the gear box ratio...my front PTO turns at 2500 RPM and the gear box seems to be a little better than 1/1...something like 1/1.125 maybe?
What is the ideal RPM of mower blades?

Ideal speed of a lawnmower blade is generally measured by blade tip speed (in feet per minute, aka FPM), this can be found from the RPMs by finding the circumference of the blade circle (in feet) and multiplying that by RPMs.

Most commercial mowers are over the "magic speed" of 16,000fpm, see here for some examples and here for a discussion on the subject. The maximum blade speed in the US is 19,000fpm, this is supposedly to limit the distance that a projectile can be launched by the blade (see the post by mattv21 here for details)

About your mower deck (RC60-71b): According to this website it takes a 20.5" blade, that gives the equation of (20.5 / 12) * 3.14 which returns 5.36416667. So, each blade has a circumference of ~5.36 feet.

With that we can take your mid pto RPMs of 2500 and your estimated gearbox ratio of 1/1.125 and work out that 1.12500 * 2500 = 2812.5.
Which would make your tip speed 2812.5 * 5.36 = 15,075fpm which is pretty good. However, if the gearbox ratio were 1.20 the tip speed would be 16,080fpm (equation: (1.20 * 2500) * 5.36 = 16,080)

So, with a mid pto speed of 2500RPMs, a gearbox ratio between 1.125 and 1.20 and a 20.5" blade, your tip speeds will be between 15,075 and 16,080 fpm.

Aaron Z

 

[/pine]

Thank you very much for the specific information and the time you took to do the calculations...very informative and helpful...

Thanks again...