Correct blades for a ZD21 ... totally confused ....

[xtal_01]

Hey!

I am a machinist and I living in rural VT .. OK, all VT is rural, our largest city is 42,000

I have a farmer across the street with a ZD21 ... 60" fabricated (he calls it commercial) deck.

He need blades.

Problem, the unit has been painted a few times now and the tag on the mower is missing.

The dealer and Kubota say I need the serial number to get the right blades.

I see there are a bunch of blades listed .... any idea how to find the right one ... or what the difference is between them?

I did a bunch of searching ... I "think" the correct blade is a K5645-34340 ... but that is a guess.

He had an old blade with "Kubota" and the number 56473434 on it.

I assume this is a K5647-3434 (or 34340) ... but I think it is the wrong blade for the machine ... even the factory thought it was wrong ... it is an H30 (what ever that means) and they "think" it is probably an H28 (again, they could not tell me what that means.

I even found on Amazon where they sell a blade that lists all these numbers ...hmmmmm

So, I am confused.

Any thoughts on how to figure out what blade this mower uses?

Thanks .... Mike

 

[hagrid]

When I ordered Oregon blades for my deck they wanted to know the arbor diameter and the overall length.

 

[xtal_01]

When I ordered Oregon blades for my deck they wanted to know the arbor diameter and the overall length.

They didn't ask me that ... but that would make sense and I can easily do that.

Thanks!

 

[North Idaho Wolfman]

Hagrid said it best!
The ZD21 only came with one deck option:
RCK60-21Z
Blades:
K5651-34330

There was no factory commercial deck option, but that's not to say someone hasn't modded one onto it!

 

[lugbolt]

ain't sure oregon has them, and i ain't had an oregon blade yet that will cut as well and last as long as kubota oem replacements. But they also don't have blades for my current mower, either. They size it by the length, and the arbor-and of the ones I've found that are "close", they are not close enough. When I worked at the dealer we had to eat several sets because of poor QC. Maybe the distributor of the Oregon stuff didn't like us, who knows. Some were so far out of balance that it wasn't feasible to try to bring them back to remotely close, others the arbor hole was too big or too small, and one set in particular the hole was off center. Only kubota blade I ever had a problem with was the RCK42P twin blade deck, sometimes they would vibrate. Regrinding them fixed it. Was 2 mowers in 2018 and never saw a problem before or after--and that was the majority of the business we had at that dealer, mowers.

 

[xtal_01]

Hagrid said it best!
The ZD21 only came with one deck option:
RCK60-21Z
Blades:
K5651-34330

There was no factory commercial deck option, but that's not to say someone hasn't modded one onto it!

Interesting ... I know his is a fabricated deck ... I have also seen a stamped deck on them.

His was only a year old when he got it ... and it is the same deck that it came with.

Interesting ,... I have not seen the K5651 number before .... just K5645 and K5647

How can there be sooooo many blades for one machine ???

Not sure if it matters but his was an early ZD21 ... did not even come with rop.

Thanks!

Mike

 

[CGMKCM]

FWIW, I have used Oregon blades on my ZD323 60" deck and the blades thickness is thinner than OEM blades. I have to use a large thick washer to get the clamping force needed to get the blades to work. Take a look at rotary brand blades if OEM blades are not available. I will add a link to the Rotary blades I order, they seem to last as long as OEM blades in my sandy soil, well balanced, only negative is the blade rides 1/4" lower than OEM.

Rotary mower blades.

 

[lugbolt]

Interesting ... I know his is a fabricated deck ... I have also seen a stamped deck on them.

His was only a year old when he got it ... and it is the same deck that it came with.

Interesting ,... I have not seen the K5651 number before .... just K5645 and K5647

How can there be sooooo many blades for one machine ???

Not sure if it matters but his was an early ZD21 ... did not even come with rop.

Thanks!

Mike

They used to (maybe still do?) sell a blade KIT, 3 blades in a box. So you had mulch blades (for the Kubota mulch kit), standard blades, and perhaps bagging blades. Then you could also get them individually which had a different part number. So that's 6 different part numbers.

Also over the years Kubota realized that some blades will fit other models and some old style blades will satisfactorily do the same job (such as mulch blades and standard blades being interchangeable), and some part numbers were superceded and/or eliminated entirely. BUT--sometimes the online and aftermarket resources (non-kubota) will iist old outdated part numbers as a cross reference to a different brand (Oregon does this) which makes it even more confusing.

RCK60P decks are considered "pro" decks. Some of them had "commerical" stickers on them. The P decks are fabricated, aka welded decks. The S prefix is a stamped deck. Weren't a lot of those put on ZD's. Since the ZD's came about, I only saw one. And they use a cheesy gearbox.

 

[xtal_01]

Hey!

Just a quick follow-up.

Thanks for your help last week.

I was able to find a picture of the two mower decks that came with the ZD21 ... RCK60-21Z and RCK60P-21Z

He has the RCK60-21Z

So he does indeed need the K5645-34340 blades ( not the K5647 ... that the local dealer had been selling him).

He told me since the dealer had been selling him the "new" blades, the machine has just not cut right.

With some luck this will solve the problem.

Thanks again ... Mike

Jericho, Vermont