Mark VII Impeller

[Ash1562]

Hello -- I've been looking through the many previous posts about this topic but can't find the answer, so thought to post anew here. Thanks in advance for your time and answers.

1. There's a small o-ring (it's really like an omega shape, but I don't know what it's actually called) behind the castle nut that keeps the impeller blade on the idler shaft. Over use, this o-ring comes out of the groove onto which it's supposed to sit and jams the impeller blade against the headstock body and it can't spin freely. I've tried replacing the o-ring but still it persists. I finger-tighten the castle nut as well -- what am I doing wrong?

2. I saw a few posts about lubricating the impeller blade/idler shaft but not sure what that exactly means or what sort of lubricant is recommended -- any comments?

3. There were a few comments about the added noise. To be sure, it's louder but not _much_ louder. But someone said the "impeller could be worn and needs to be replaced" if it's too loud - what does this mean? the blade needs to be replaced?

4. Lastly, is there a way to test if the impeller is working properly? I know this isn't a vacuum system so I can't just go around sucking up sawdust but how do I know if it's working as intended? Is it simply if I sneeze less? ha

thanks all!!
Ash

[JPG]

Is it possible the retaining ring is getting stretched when being installed and thus does not grip the shaft(in the groove) tightly? Is the side of the groove worn?

It should suck up sawdust, but not as well as a vacuum.

Replace the impeller? With what from where?

Lubricate the shaft ?????

[Ash1562]

I realized the cotter pin is missing. Bought one and popped it on. Did I

SmartSelect_20221015_154243_Gallery.jpg (92.89 KiB) Viewed 813 times

install this correctly?

[JPG]

Mine had an external tooth lock washer.

viewtopic.php?t=11986

Scroll waaaaay down.

[miken]

I have the exact same issue with mine. The groove on the motor shaft that the snap ring fits into is worn on mine which allows the snap ring to work it's way out. I ran the motor and used a needle file to clean up the groove and make the edges somewhat square again. I also switched from a snap ring to an e-clip which fit tighter. It worked. However, as mentioned, it's not a great vacuum. I removed it and use a shop vac. If the problem would have persisted my next fix was going to involve drilling a very small hole and adding a roll pin, but the SS vacuum performance simply isn't worth it to me.

As JPG mentioned adding the lock washer will help some, if you fix the snap ring issue. Maybe on yours the cotter pin is all you'll need?

Mike -

[Ash1562]

Thanks a lot, Mike. I feel validated. I also filed the groove and so far, the retaining ring is holding. The cotter pin is also working but it's not been too many hours yet of use.

I debate the efficacy of this impeller constantly. I know to not expect it to be a shop vac but more of a high volume/low pressure deal. But, since everything else on this machine is genius and simple in design, the purist in me says trust the wise ones who made this. Or maybe, back then shop vacs were crap and this is all they had!

[Ash1562]

Does anyone know how or where to get more of those spring clamps that fit on the blower housing? Mine has only ever had one and I've always just used tape, which probably isn't the best idea.

[rpd]

I would be more inclined to install the cotter pin turned 90 deg, so the ends wrap around the nut, rather than sticking out.