The 2100 series (Ambassador. LE, etc.)plastic canister vacs have dual stage motors in them, just like the older electrolux's.
That being said, I gave away to my SIL, one of mine that I upgraded to an Ametek Lamb motor (5.7"). I am currently working on another one that I am upgrading.
Here are some pics of when I was test fitting the Ametek Lamb motor.
the 2nd pic is a comparison of an original 2100 motor compared to the Super J motor. A 5.7" motor cannot fit in the Super J body, but will fit in the later metal canisters like a Silverado and later. (They made the hole larger in the metal body).
It is very easy to find the Ametek Lamb motors. The latest one I got was less than $20 (with shipping) and is only 2 years old.
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