[AJD] Another trivia question - Pre-Screeners??

[Dean VP]

Over the years I have looked for a couple good used Pre-Screeners and have
found and installed one on my 620. At the time I came to the conclusion that
the can type with the round holes were for 20 and 30 series and the
stretched metal - diamond type holes were for the New Generation tractors.
Since I was buying used I didn't know the exact Part Number for what I was
buying. The Parts Catalog illustrations for the 520 through 730 show the
round hole type but I am aware that these illustrations cannot always be
trusted for accuracy. But up until the following two eBay auctions I thought
I had come to the correct conclusion.

The two eBay auctions are just the reverse of my thinking.
 
7564613408 - Round holes. New Generation. 

7564613448 - NOS Stretched metal - diamond holes. 520 - 730

Now I suspect since the second one is NOS and has the part number on the box
there is a good chance this is right. 

But it is totally reversed from my previous conclusion.  Does anyone on the
list have a clear precise definition as to what was used when? Or did JD
make a change during production w/o changing Part Numbers? Or were both
types used interchangeably? 

 
Dean A. Van Peursem
Snohomish, WA 98290

Forbidden fruits create many jams!

www.deerelegacy.com

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