QA-42A - blew up the input gear today

[gary noblit]

I knew a fella once or I think I did....It seems most folks run a machine,park it and hope it works next time .It's kinda like the mower buried in the snow attitude. I hear it often,"it ran last year".

 

[mfrade]

It ran when I parked it!

 

[gary noblit]

Mike,it may take a day or 2 but I believe I can get it to purr..hard part might be getting the dang tree to let go.....neat pic !!!

 

[rfunk]

Made the mistake of using just gear oil. If the gearbox doesn't sit level in storage, it leaks through the bearings. (My gearbox is too short to put the seal in at the end). Probably will get a grease/oil mix when I get the thrower together. P/O made an adapter to fit the 149 wide frame, but the belt adjuster hits the frame, so either can't get the belt tight, or can't get it on . . . also the shaft sits not parallel to the crankshaft, so I need to do some work. Only upside, have not had enough snow yet this winter, to need it. Backup is a 1965 Eaton's 6.5Hp Techomaster walk-behind. Haven't needed that, either.

 

[mpatterson]

Well I got the parts QA-42A ripped apart today. Gears seem to be good so far. Need a good cleaning though!
Didn't expect the bearings to be different thicknesses though. Knew the inner ones wouldn't have seals thanks to Hydro Harry kicking in.

 

[hydroharry]

Mike - glad to see you're getting there. Every time I look at the weather for your side of the border, it's snow snow snow

Hey - have a good look at the key way on the gearbox output shaft that goes to the driveshaft. Most of the QA's I've seen have the allen screw locking the drive shaft to the output shaft, on the opposite side of the key way. Hope your's has the allen screw above the key on the key side of the driveshaft. Otherwise the dang allen screw comes loose and the key starts to twist in the key way until it just spins and ruins the shaft. I've seen just a few driveshafts that are done correctly with the allen screw hole going thru the key way side.

 

[mpatterson]

Mike - glad to see you're getting there. Every time I look at the weather for your side of the border, it's snow snow snow

Hey - have a good look at the key way on the gearbox output shaft that goes to the driveshaft. Most of the QA's I've seen have the allen screw locking the drive shaft to the output shaft, on the opposite side of the key way. Hope your's has the allen screw above the key on the key side of the driveshaft. Otherwise the dang allen screw comes loose and the key starts to twist in the key way until it just spins and ruins the shaft. I've seen just a few driveshafts that are done correctly with the allen screw hole going thru the key way side.

We actually got our first good snow storm over the weekend - about 6" or so of wet, sticky, heavy snow! We've been spoiled so far this winter actually.

I do have set screws on the input side - the small pully I still have to take off has two of them. Only problem - there is no key in the key way!! The pully has turned half a key way I see. Hope the shaft is still good, I want to use it! Will know more when I get the bearing and pulley off it. I was using a 2 piece pully on my original QA. It has the bolt in hub that tightens it onto the shaft. So hope to re-use it on the newer shaft once cleaned up. Have to get fathers puller to get them off the shaft.

Still need to get numbers off the bearings and seals to see if can source them locally. Worst case, I know Digger has them.

 

[hydroharry]

Mike - I was talking about the set (allen) screws on the driveshaft. Most of the driveshafts don't have the set screw locking down the key way. Can you post a pic of your driveshaft so we can see if this is the version you have?

 

[mpatterson]

Picture of drive shaft Harry

Is there a chart somewhere that tells you the length of chain needed for 24 vs 26 inch tires? Have this set of tire chains I may look to repair the few links in it if I knew it fit specific sized tires.
Just asking short of trying to make them fit a tire. Figured someone else had found chains before!?
Was debating putting them on my ag tread Firestone

 

[sblunier]

I extended a set of 10.50 to fit 26x12 once.....I have a set of 26x12 off tractor in shed, I could measure them if you want.

 

[hydroharry]

Mike - I can see one of the allen set screws is directly over the key slot, so you have one of the best drive shafts. Many of them have the allen on the opposite side of the key slot - which is a poor design.

Also, about the chains. Hopefully Steve can tell you the number of individual twisted links are in each cross section, and the number of links the entire length of one side for his 26x12x12. I suggest this because taking actual measurements is pretty difficult with chains.

 

[mpatterson]

Steve,
Yes if you could do that sometime, I'd appreciate it! Would be nice to have them on the Firestone's for hauling the firewood trailer this winter. I have just enough of an incline in 4 spots on my lawn that when loaded I spin the tractor tires going up it. IF these will fit properly that they are not moving around and tearing up the lugs on my tires, they will be a great addition. Still think I'm going to load my ag tires with washer fluid. It seems my a$$ isn't as heavy as it once was??

Harry,
Good to hear I have something worth something for once!
I know Steve has the info I will need - just need to be patient to receive it. Busy man. I don't want to be the resulting PIA problem that holds up his production in the shop. I know the job he's dealing with now - I wouldn't want to have to do it.

 

[sblunier]

17.5" wide x 55" long.

 

[sblunier]

When reassembling shafts, tighten set screw on top of keyway FIRST, then the one 90deg offset. Keeps everything good and tight.....

 

[hydroharry]

When reassembling shafts, tighten set screw on top of keyway FIRST, then the one 90deg offset. Keeps everything good and tight.....

Yes Steve - that's the correct way to tighten the set screws when you have 2 of them. The issue I was getting at is that several of the QA driveshafts I've had over the years only had 1 set screw and instead of being above the keyway it was on the opposite side. I never understood why it was done that way. Mike seems to have the best style where there are 2 set screws, 1 above the keyway and 1 at 90degrees from the keyway.

 

[mfrade]

Harry, it was done that way to keep the majority of the key in contact with the keyway. Old School machining would not tighten the screw above the key first. The general idea was to keep the space around the key and keyway to a minimum, full engagement.

I am NOT debating what is right or works for anyone. Just stating how I was taught to assemble this arrangement. Screw over key would be last to get turned. Key & keyway held tight together.

 

[hydroharry]

Harry, it was done that way to keep the majority of the key in contact with the keyway. Old School machining would not tighten the screw above the key first. The general idea was to keep the space around the key and keyway to a minimum, full engagement.

I am NOT debating what is right or works for anyone. Just stating how I was taught to assemble this arrangement. Screw over key would be last to get turned. Key & keyway held tight together.

Mike F - not sure you're still getting what I stated. There was only 1 set screw on many of the driveshafts I've had over the years. How the heck do you keep it tight? Have you ever seen a pulley (sheave) with 1 set screw AND not on top of the keyway? I haven't and don't understand why a driveshaft would be that way.

 

[mfrade]

Harry - I get it. I am not specifically talking about cub cadets. I have seen many combinations of attaching a hub and shaft.
All I was saying, in my training, if a setscrew was on the opposite side of the key tighten it first to pull the hub onto the key.
If you tighten the screw above the key first, you pull the hub away from the shaft and key.and that is not desirable. You said you didn't understand why it would be done that way. That is why. That's all I am saying, not saying anyone is right or wrong in regards to the cub cadet.

 

[sblunier]

Mike F.

I agree if they are 180 degrees from each other there is merit to full key engagement. In this case, the thrower driveshaft has them 90 deg apart. In this configuration, tighten keyway first, then 90 deg out.

 

[hydroharry]

I certainly agree with Steve. I can't agree with Mike F (which is quite unusual). If you have 2 set screws 180 degrees apart then you tighten the one opposite the key way first. If you have 2 set screws 90 degrees apart then tighten the one directly over the keyway.

The issue I raised to begin with was that some of the drive shafts only have ONE set screw and it's 180 degrees from the key way. There is NO set screw over the key way. I really hated these drive shafts and thought it was a mistake by who ever made them for IH.