McKee/JD 7 ft blower PTO questions

[Fakker]

Hello,

I bought a McKee which i do believe is actually a 7ft John Deere and have fixed it all up. Now I am confused how to hook the PTO shaft to the implement. It is my first implement. The PTO shaft at the implement end has a key way and the connection on the blower has a key way and what looks like a shear bolt that has sheared and stuck in the hole. The two key ways seem to be different sizes. There is also a small bolt on PTO knuckle that does not line up with the key way. I have included pictures. Any help appreciated. THX.

 

[Bentru]

I have the McKee version and a JD manual to go with it. I will look in the manual tonight and get back to you. From what I see, that isn't a sheared off bolt, it is simply a dent left when someone tightened the set screw. Do you have a key for it?

 

[07wingnut]

Also welcome to the forum.

The end shown in the first photo is the end that attaches to the snow blower. It slides onto the snowblower stub shaft and is prevented from slipping on that shaft by the key . The bolt that is sheared off is not a shear bolt, it is meant to prevent the pto shaft from slipping off of the blower stub shaft. It likely fatigued and broke because the pto shaft is constantly moving back and forth due to there being a tiny amount of play even with the bolt inserted and the nut tightened. This play is supposed to be prevented by tightening the square headed set screw shown in the fist pic. Hope this helps.

 

[Bentru]

I have the McKee version and a JD manual to go with it. I will look in the manual tonight and get back to you. From what I see, that isn't a sheared off bolt, it is simply a dent left when someone tightened the set screw. Do you have a key for it?

I checked and mine does have a bolt, not a set screw. If you really have a broken off bolt, press/pound it out and us another of the same size. Did you determine yet if the keyway on the shaft and the keyway on the gear box match?

 

[Fakker]

I checked and mine does have a bolt, not a set screw. If you really have a broken off bolt, press/pound it out and us another of the same size. Did you determine yet if the keyway on the shaft and the keyway on the gear box match?

The keys are different sizes, one is 3/8 and one is 1/4. Tried to pound out what could be the bolt that is in blower input shaft but it will not budge. Also if it was supposed to be a bolt would there not be 2 hole through the yoke for the bolt and nut. Only hole in yoke is for Set screw. Also, the blower is a McKee 620. What does your manual say Bentru.

 

[pmsmechanic]

I'm thinking the divot in the shaft is for the set screw. If a bolt was broken off in the shaft you should have been able to move it by hammering on it.

Search for an "offset key" or "step key" or ask at a Grainger Supply or equivalent and you can buy a key with one side 3/8" and the other 1/4".

That should get you going!

 

[Bentru]

My manual is very vague when it comes to the PTO shaft. It shows the U-joint and the stub coming out of the gearbox. No indication of key, bolt, setscrew, etc. If it were me, I would either get a new shaft from TSC or elsewhere, or take the shaft to a machine shop and have a new yoke put on it. Your other option is to get a stepped key. You could probably get one online from Zoro Tools.

 

[Dave M7040]

The real guru on these McKee John Deere blowers is a forum member "Eric the Oracle."

He has had posts with links to manuals and parts .

I had a 720 for 25 years.

The shaft and lower pto yoke likely have the same size key but the female yoke likely requires a bit of work with a flat file to restore the width to the proper size. It looks like the key sheared and mushed the keyway.

The set screw never kept the yoke on the gearbox shaft and most owners drilled a hole through both and used a bolt and lock nut along with the key.

The shear bolt is at the tractor end of the pto shaft.

The pto shaft's smaller shaft should have a steel ball pressed into the shaft and the larger half will have a groove for the pressed in ball to slide in. This provides critical indexing of the pto shaft. Often owner's, unaware of the pressed in balls importance, cut that part of the shaft while shortening the shaft, then reassemble without indexing and the shaking will pull anything apart.
.
The blowers are tough and durable. The shortcoming is the 3 blade fan. On tractors with too high a reverse gear, the blower has a hard time getting rid of the snow delivered by the auger. If you have low reverse gears, you will be fine.

I don't know if these links will still work.

A-JD92�9 BEARING, BALL | AllPartsStore

NPS1�6RPC - Bearing With Lock Collar - Shoup Manufacturing

This image with the marked up yellow triangle is an improvement worth trying.

If you look at modern blowers, all have this piece to retain the snow on the fan blades. It would be easy to fabricate and bolt on.

This is the spec table for various McKee models.

Parts diagrams. the 270 is the John Deere descriptor and the McKee would be the 720. The 620 and 720 used many of the same parts

Dave M7040

 

[MinnesotaEric]

Hello,

I bought a McKee which i do believe is actually a 7ft John Deere and have fixed it all up. Now I am confused how to hook the PTO shaft to the implement. It is my first implement. The PTO shaft at the implement end has a key way and the connection on the blower has a key way and what looks like a shear bolt that has sheared and stuck in the hole. The two key ways seem to be different sizes. There is also a small bolt on PTO knuckle that does not line up with the key way. I have included pictures. Any help appreciated. THX.

Looks like 1/4" key stock and a through bolt sized accordingly and you're all set up. You're sheer bolt is on the other end of the driveshaft. If needed I can go take a photo of how my shaft is mounted as my blower is still in my driveway.