451 Snowblower with Loose Impeller
 

I have a 190-451 snowblower mounted on my Cub 1862.

I was blowing some snow last week. Stopped to clear a snow jam, and noticed that the impeller seemed a bit loose. I finished the job, pulled it into the garage, and let everything dry.

The next day, I pulled off the exhaust deflector, belt cover, and discharge chute assembly for a good view of the blower’s gear housing and belt pulley, and to provide better access to the impeller, which I wiggled around by hand.

The impeller was indeed loose – I was able to rotate it on the shaft about ½” at the outside diameter, and wiggle it about 3/8” forward and back horizontally. Also, I was able to wiggle the shaft about 1/8” up / down at the end nearest the impeller; the front end of the shaft (at the spiral gear housing) was tightly secure.

All other parts appeared tight and completely functional. There were no unusual noises or other symptoms.

To anyone who has (or had) a 450 or 451 snowblower: is this much ‘play’ in the impeller normal, or I looking at an impending failure?

Thanks in advance,

Jon

Hi Jon,
Just so we're on the same page, the auger feeds the snow into the impeller which flings it out.

The 1/2" of radial movement doesn't sound that bad, the 3/8 fore and aft movement makes me wonder if a collar is loose. As far as the 1/8 movement, is that secure or free floating?

( I'm a narrow frame guy myself and use a QA42 )

Jeff

Hi, Jeff -

Thanks for your reply!

The 451 is a two-stage blower, with a pair of augers and an impeller. I'm referring to the impeller.

I had this whole thing ripped apart a year and a half ago for rust removal, paint, and general p.m., and I didn't see anything resembling a collar. The impeller is secured to the shaft by means of a spirol pin. Both the impeller and shaft are splined where they mate, and both splines showed virtually no signs of wear when I had the entire unit disassembled.

I'm not sure I understand your question about the 1/8" movement at the rear of the shaft.

Thanks for your help -

Jon

Is the front ( auger end ) of the impeller in a bearing/sleeve or just hanging out in mid air?

Sounds like the splines are getting worn on the impeller.

Here's a link to a thread with a guy who repaired his......450/451 snowblower fan spline repair

Jeff -

The front of the impeller is connected to a shaft through the impeller itself. The front of the impeller shaft is connected directly to the spiral gear housing (i.e., the auger gearbox). Hope my description is adequate.


Jonathan -

Thanks for that link; you might be on to something...

"I think the main cause was that the gearbox shaft was not set deep enough into the fan splines. There is alot of in and out adjustment for the gearbox and you could tell only half the spline depth was engaged. I'm also thinking that the PO engaged the PTO at full throttle and not at idle."

When I reassembled everything, I vaguely recall being concerned that the splines on the gearbox / impeller shaft did not penetrate deeply enough into the mating splines on the impeller (fan).

I had hoped for a 'magic bullet' fix, since the blower is mounted on the tractor, and I was hoping to avoid removing the auger / gearbox / impeller assembly. I'm starting to think I'll need to look at the splines to see what's up.

Any other ideas? Anyone?

Thanks a bunch!

Jon

Follow-up:

Got 'er done! Without pulling the auger / gearbox / impeller assembly out from the housing (or removing the snowblower from the tractor), I removed the drive belt for a better look at rear gearbox. I noticed that with some adjustment of the rear gearbox support brackets, I could bring the gearbox about 1/2" closer to the back side of the housing, thus forcing the splined shaft further into the splines of the impeller - and so I did.

When I resecured everything, the impeller still had some slight rotational movement on the shaft, but otherwise was pretty tight. Quite an improvment!

Jonathan, thanks again for posting the above link! After I re-read it enough times, the light bulb came on. It pointed me right at the problem, and a (reletively) easy fix.

I never did have to inspect the splines. Guess I'll find out soon enough whether there was any hidden damage.

Jon

That's great news Jon :beerchug:

Glad to hear it!