Yardvacuum Impeller Removal

Gravelier

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You said that you encountered resistance after threading in the 7/16-20 bolt a couple turns. Then you were able to force a couple more turns before encountering high resistance. Have you tried running a tap into the hole to see what comes back with the tap? If you are getting 4 turns into the hole, it seems like the bolt and threads are correct and that you have crap in the threads. You can feel the difference when running in the tap if you are cutting metal (cross threading the existing threads) or removing debris. Don’t cut metal with the tap. Another method is make a chaser with the 7/16-20 bolt. I use a 3-corner file to undercut the threads. I tried to upload a picture but I get a msg that it’s too large to upload from my iPad. Good luck
 
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l008com

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I don't own a tap kit, I've been asking around to borrow one but coming up empty so i'll probalby go buy a HF kit after the holidays.

I also had the idea of getting a stick of hot glue or a crayon, an slightly melting it into the threads. The once it cools, popping it off and then comparing the threading of the glue stick to the threading of the bolt itself.
As far as dirt in the threads, it looked clean and it didn't feel like i was binding on dirt, it felt like the threads were wrong. But who knows.
 

Gravelier

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You said that you encountered resistance after threading in the 7/16-20 bolt a couple turns. Then you were able to force a couple more turns before encountering high resistance. Have you tried running a tap into the hole to see what comes back with the tap? If you are getting 4 turns into the hole, it seems like the bolt and threads are correct and that you have crap in the threads. You can feel the difference when running in the tap if you are cutting metal (cross threading the existing threads) or removing debris. Don’t cut metal with the tap. Another method is make a chaser with the 7/16-20 bolt. I use a 3-corner file to undercut the threads. I tried to upload a picture but I get a msg that it’s too large to upload from my iPad. Good luck

I don't own a tap kit, I've been asking around to borrow one but coming up empty so i'll probalby go buy a HF kit after the holidays.

I also had the idea of getting a stick of hot glue or a crayon, an slightly melting it into the threads. The once it cools, popping it off and then comparing the threading of the glue stick to the threading of the bolt itself.
As far as dirt in the threads, it looked clean and it didn't feel like i was binding on dirt, it felt like the threads were wrong. But who knows.
I have several tap and die sets. The one that is from HF I only use to chase or clean up threads. I don’t feel it’s strong enough to cut new threads. If I need to cut new threads (tap or die) I use my old craftsman set. Best of luck.
 

l008com

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Hmm well maybe I'll try my crayon thing and see if the threads are close, or way off, and go from there.
 

Markdd60

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There's a reason some have stated using 7/16-20, the M11-1.25 only exist for special applications..... go figure. 7/16-20 = 11.1125 (slightly larger than M11). M11 general tap drill size = 9.75mm / 7/16-20 general tap drill = 9.9218mm (close enough for sure). You already have the existing threaded hole, pick up a 7/16-20 plug tap... local auto or hardware. Those impellers are like cast aluminum it seems, pretty easy to cut new threads.... use a few drops of oil. Be gone silly M11-1.25! 😆
 

l008com

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Yeah thats what I'm thinking at this point. I don't do thread tapping very often so I'm trying to decide how much of an investment in taps to make. I can just get an individual tap or I can get a whole SAE set or I can get a whole combo SAE & metric set. Decisions decisions. Next weekend I should have time to figure this out.
 

StarTech

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I don't own a tap kit, I've been asking around to borrow one but coming up empty so i'll probalby go buy a HF kit after the holidays.

I also had the idea of getting a stick of hot glue or a crayon, an slightly melting it into the threads. The once it cools, popping it off and then comparing the threading of the glue stick to the threading of the bolt itself.
As far as dirt in the threads, it looked clean and it didn't feel like i was binding on dirt, it felt like the threads were wrong. But who knows.
I would not waste my money on the HF taps and dies. I brought two set and both were junk and had to return them then I got a couple Vermont American set. NOw of course that was 15 yrs ago and have only replace one tap so far.
 
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