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Yardvacuum Impeller Removal

#1

l008com

l008com

So I watched a bunch of youtube videos for removing the impeller off my machine. This is so I can ultimately take the motor off and open it up because I think it overheated and melted it's camshaft. But anyway....

Multiple videos say to use a 7/16" - 20 bolt. So I go pick one up and when I go to thread it in, nada. Totally the wrong threading, although the diameter seems right.

So what's going on here? Did I buy a bolt with the wrong threading? Certainly possible someone could have put it in the wrong spot on the nut and bolt wall at the hardware store. Easy enough to check if someone can tell me what the " - 20" is. Is that like threads per inch or theads per something?

OR does my impeller just need something other than - 20 threading? Unfortunately you need this bolt to remove the impeller so I can't just bring it into the hardware store and try every size until I find one that works - which is what I normally do in a situation like this :D

BUT I do have a picture, maybe you guys can tell just by looking?
bolt-and-hole.jpg

Assuming the "20" is the threads-per-inch, it looks like I have 19 threads per inch here. I assume that missing thread is just the perspective of the camera. So it is a -20 bolt, so I guess I need something else you think?
threads.jpg

Oh also here's the model number(s) off the machine itself:
24A-070J799
247.77013.0

And the serial number is:
1H198G70100


#2

ILENGINE

ILENGINE

I have found a few references to spindle removal tool for MTD products



#3

l008com

l008com

I don't need the whole tool. I just need a simple short bolt to thread i to teh impeller. I can use a piece of rod or something else to be the "insert" it pushes against. Plus the reviews on that thing to not look good. And it looks like there are more than one threading these impellers have so it all leads back to the same question, which size threading am I looking for. I guess I forgot to include my machine model number in the original post.


#4

ILENGINE

ILENGINE

Went and measures the threads on my DR impeller removal tool and they are 20/inch. but it measures .327 in diameter which is smaller than 7/16 but doesn't match up with anything else. From the picture it looks like the threads in your impeller are damaged so they could be flattened causing issues with your bolt.


#5

l008com

l008com

Yeah I don't get it, 7/16-20 is what this bolt is and the threads aren't right at all. YOu have to go through the impeller threads to get to the crankshaft threads so I'm nowhere near those.


#6

StarTech

StarTech

The tool pushes the impeller off so it is design to pass the 3/8-24 threading of crankshaft and bottom out in the blind hole. This prevents the tool from pushing on the end of crankshaft damaging the threads.

Matter of fact any puller that pushes against a shaft should have a sacrificial intermediate block (shaft protectors) as even those pullers can also damage threading without these. They also help prevent the shaft that being press against from flaring.

Here is an example of one in use.
1733833353381.png


#7

l008com

l008com

Yeah but what I'm saying is that I can't get this bolt to thread into the initial threads that it is supposed to engage with. Once I can get it to engage, I can throw any old rod in the hole to act as a spacer/pusher so I don't to any damage to the threads on the motor shaft. But I can't do that until I get a bolt that will actually thread in to the impeller, which seems to be my problem. When I started to thread this bolt in, it got a few turns in but it was getting tighter and tighter until it basically stopped. It's gotta be a case of the wrong threading.


#8

ILENGINE

ILENGINE

Could it be metric thread.


#9

l008com

l008com

I guess, it could be.


#10

StarTech

StarTech

Sounds like it is a M11-1.25 thread very close to 7/16-20 but is tight two ways. 7/16-20 are drilled out at .390 and M11-1.25 is drilled out at .384 and the pitch are slightly different too. Looks the same but are not.

It will nearly impossible to find a M11-1.25 screw.


#11

l008com

l008com

Hmm maybe I'll go pick up an M11-1.25 then and see if that fits any better.


#12

Tiger Small Engine

Tiger Small Engine

l008com said:
So I watched a bunch of youtube videos for removing the impeller off my machine. This is so I can ultimately take the motor off and open it up because I think it overheated and melted it's camshaft. But anyway....

Multiple videos say to use a 7/16" - 20 bolt. So I go pick one up and when I go to thread it in, nada. Totally the wrong threading, although the diameter seems right.

So what's going on here? Did I buy a bolt with the wrong threading? Certainly possible someone could have put it in the wrong spot on the nut and bolt wall at the hardware store. Easy enough to check if someone can tell me what the " - 20" is. Is that like threads per inch or theads per something?

OR does my impeller just need something other than - 20 threading? Unfortunately you need this bolt to remove the impeller so I can't just bring it into the hardware store and try every size until I find one that works - which is what I normally do in a situation like this :D

BUT I do have a picture, maybe you guys can tell just by looking?
View attachment 70231

Assuming the "20" is the threads-per-inch, it looks like I have 19 threads per inch here. I assume that missing thread is just the perspective of the camera. So it is a -20 bolt, so I guess I need something else you think?
View attachment 70232

Oh also here's the model number(s) off the machine itself:
24A-070J799
247.77013.0

And the serial number is:
1H198G70100
Click to expand...


If you can get the engine opened up, can you show us pictures of what a “melted camshaft “ looks like please? Lobes can be compromised, but never heard of a small engine turning 3600 RPMs, melting a cam.


#13

l008com

l008com

The whole project will be a youtube video some day. I don't have any idea what the camshaft is going to look like, but what I do know is:
The camshaft is plastic
The engine was running well when I first started it up.
It died and had zero compression when I tried to restart it.
The compression came back but with the valve cover off, the valves were opening and closing at the complete wrong times.

Also I didn't know when I started it up but it had a lot of leaves and similar yard waste packed up under the cover.

So the only thing that makes sense to me is that the came shaft melted to some degree. I'l find out eventually.


#14

l008com

l008com

My local hardware store has two big isles of all nuts and bolts. But alas, they only had even numbered mm bolts, no 11mm at all. I grabbed a 10mm just to see but it fit right through the hole without engaging the threads at all.


#15

StarTech

StarTech

I tried to tell you that it is a non standard size. About the only fairly local place that might have an used one is the Toyota Dealer repair shop since it is used as a head bolt.

Now you know why they said to drill for a 7/16-20 tap and tap it for the 7/16-20 bolt.

OR you just buy a set of 8 for around $50+ from the auto part store.


#16

l008com

l008com

Hmm I guess I'll have to consider re-tapping the whole, that might be the easiest solution.


#17

L

Laabk2

l008com said:
So I watched a bunch of youtube videos for removing the impeller off my machine. This is so I can ultimately take the motor off and open it up because I think it overheated and melted it's camshaft. But anyway....

Multiple videos say to use a 7/16" - 20 bolt. So I go pick one up and when I go to thread it in, nada. Totally the wrong threading, although the diameter seems right.

So what's going on here? Did I buy a bolt with the wrong threading? Certainly possible someone could have put it in the wrong spot on the nut and bolt wall at the hardware store. Easy enough to check if someone can tell me what the " - 20" is. Is that like threads per inch or theads per something?

OR does my impeller just need something other than - 20 threading? Unfortunately you need this bolt to remove the impeller so I can't just bring it into the hardware store and try every size until I find one that works - which is what I normally do in a situation like this :D

BUT I do have a picture, maybe you guys can tell just by looking?
View attachment 70231

Assuming the "20" is the threads-per-inch, it looks like I have 19 threads per inch here. I assume that missing thread is just the perspective of the camera. So it is a -20 bolt, so I guess I need something else you think?
View attachment 70232

Oh also here's the model number(s) off the machine itself:
24A-070J799
247.77013.0

And the serial number is:
1H198G70100
Click to expand...
According to the parts diagram it is a 3/8-24 bolt 2.75 inches long


#18

l008com

l008com

Are you referring to the removal tool or the bolt that holds the impeller on to the motor?


#19

L

Laabk2

l008com said:
Are you referring to the removal tool or the bolt that holds the impeller on to the motor?
Click to expand...
The bolt that retains the impeller.


#20

l008com

l008com

I'm not looking for that, I'm looking for the threading in the impeller itself, that you would use with the removal tool or with the right sized bolt, to remove the impeller.


#21

L

Laabk2

Oh, sorry my bad, misread what you were looking for.


#22

S

smallenginesuppliers

Looks to me like it should be 3/8-24. See the link below (reference 31)


#23

l008com

l008com

smallenginesuppliers said:
Looks to me like it should be 3/8-24. See the link below (reference 31)
Click to expand...
Please see the previous 5 posts.


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