Gas leaf blower impeller nut keeps coming loose

[branimal]

I've got an old Craftsman 32cc leaf blower. It's was working pretty good this past fall. Around Christmas time she's was running really rough and the engine stopped running. I couldn't get it to restart. I put it away for the season but took a look at it last night.

I opened the door on the lower housing and the impeller nut was very loose. I could hand tighten it. I tightened it up with a 9/16" socket and I noticed the pull cord (which alway hung loose out of the blower body) started pulling in snug. I'm thinking I've got this thing fixed. I started her up and within seconds she's dead.

I repeated the above steps and the same result - engine starts and quickly dies. Each time I find that nut is super loose.


Here's the diagram from the manual and some pictures.

Any ideas on how to fix this?

Thanks.

 

[Soundq1-150]

Have you tried putting some Loctite on it? That should hold it just fine once it is cured.

 

[Leaflessshadetree]

Is there a key to hold it on the shaft? May have sheared.

 

[branimal]

Have you tried putting some Loctite on it? That should hold it just fine once it is cured.

I haven't. I could use some red loctite, or maybe even a locking nut. But I'm thinking something is causing it to come loose. Like the loose nut is the symptom and not the problem.

The other thing i'm not sure of is how hard do you need to crank this down.

Thanks.

 

[branimal]

Is there a key to hold it on the shaft? May have sheared.

I don't see a key on the diagram I posted.

 

[BillK]

I would almost bet that there is a keyway. If you pull the nut and washer off can you see a slot in the impeller ? Or pull the impeller off and take a look. Take the nut and washer off and post a picture. Very hard to see your diagram.

As far as how tight it depends on what size the threads are ? I would probably say a minimum of 30 ft lbs but it hard to say for sure.

 

[Innovate1]

I don't see a key on the diagram I posted.

Some parts like that have the key cast into the hub so there won't be a key on the parts list. You are going to have to take it apart to tell. Removing the nut and washer will probably let you see the keyway if there is one.

 

[Justind97]

I see what looks like a little tab on the washer directly behind the nut, is this correct? If so, that's supposed to be pried forward toward the nut to lock it in place.

If not, steel locking nut with red locktite.

 

[branimal]

Here are some pictures:

 

[BillK]

So by the looks of it the hex part that drives the rotor is worn or the rotor itself is worn allowing it to move back and forth ? It looks like the hex part of the drive is replaceable ? Item 94 in your diagram ? That might help tighten everything up some. When you tighten the nut is it actually tightening the rotor ?

 

[BD1]

I had a similar issue with a plastic drive pulley on my HF 1" belt sander. I drilled hole in plastic pulley and in shaft. I used a roll pin but a cotter pin will work.


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[joey1320]

The impeller looks worn out causing it to vibrate, causing the nut to loosen.

I would recommend a new impeller and if not available, maybe epoxy it into place. An oversized washer for more contact pressure and a locking nut.

Good luck.

 

[LS6 Tommy]

So by the looks of it the hex part that drives the rotor is worn or the rotor itself is worn allowing it to move back and forth ? It looks like the hex part of the drive is replaceable ? Item 94 in your diagram ? That might help tighten everything up some. When you tighten the nut is it actually tightening the rotor ?

X2. It will always work itelf loose until you replace the worn out impeller.

Tommy

 

[branimal]

So by the looks of it the hex part that drives the rotor is worn or the rotor itself is worn allowing it to move back and forth ? It looks like the hex part of the drive is replaceable ? Item 94 in your diagram ? That might help tighten everything up some. When you tighten the nut is it actually tightening the rotor ?

So there is a tiny bit of play when rotating part #94. Let’s call it’s the impeller washer. The “D” hole might not be a perfect “D” anymore.

But the impeller washer seems to move the spindle with some force.

Where can I find a replacement? I looked online and I’ve found nothing.

Maybe I can search for a D washer with the same ID.

 

[branimal]

When I look really close at the D washer it is worn out a bit on the flat corners.

 

[nadogail]

Does Sears still sell parts?

 

[BillK]

Sears would be my first place to check. If not, try these guys:
https://www.jackssmallengines.com/
They have always had anything I needed.

Most of that type of equipment is all made by MTD and the parts are all the same.

 

[BillK]

So there is a tiny bit of play when rotating part #94. Let’s call it’s the impeller washer.

Ok, My mistake. Look at part number 93 Kind of hard to read the numbers in your diagram.

 

[branimal]

Sears would be my first place to check. If not, try these guys:
https://www.jackssmallengines.com/
They have always had anything I needed.

Most of that type of equipment is all made by MTD and the parts are all the same.

Good tip on that website. I searched Google for both #93 & #94 (both parts might be worn out). Found nothing.

jackssmallengines has them both.

I'm going to pull off the impeller to see if there are any problems further upstream and get all the parts I need in one order.

In the meantime, I'm going to try a locknut just to see if it keeps the engine running.


#93 impeller hub 530-029118
#94 washer 530-015818


Thanks.

 

[branimal]

I put a lock nut on the impeller hub and cranked her down good. She started right up and ran fine.

Thanks guys.