Farm Equipment - What sprockets for AC 74 Planter

What sprockets for AC 74 Planter

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Topic: What sprockets for AC 74 Planter

Posted By: biga55
Subject: What sprockets for AC 74 Planter
Date Posted: 14 Mar 2012 at 8:39pm

I have a 74 planter and I need to know what sprocket to use on the drive and the driven for planting corn with a 24 cell plate. I will use 30 in rows and need a population around 30000. My other problem is one of my planters has been replaced with a 50 series planter with size 32 chain and I cannot find sprockets for it. Once i know what sprocket to get my population, I will try and find the right sprockets for it. Right now the 50 series has 14 tooth on drive and 13 on the driven. My 74 has 20(or 10) drive and the driven has 30(15) tooth sprocket. If sprocket are equal in number on both planter will they plant at the same rate, assuming the plate is the same? Thanks for any help!!

Replies:

Posted By: bigbird
Date Posted: 14 Mar 2012 at 9:33pm

I may still have a chart for the sprockets on the 74 unit. I'll look tomorrow a let you know

Posted By: biga55
Date Posted: 15 Mar 2012 at 5:59pm

Thanks, Bigbird!!

Posted By: bigbird
Date Posted: 15 Mar 2012 at 8:43pm

Sorry, I looked today and must have gotten rid of book when planter went. I did look on AgcoParts.com, but not there either.

Posted By: Dave (Mid-MI)
Date Posted: 15 Mar 2012 at 9:01pm

From the 74 unit OM: 29,900 population on 30" rows = 7.0" seed spacing.

With a 24 cell plate, use 13T driving and 8T driven sprockets for 6.90" spacing. For 7.20" spacing, use 14T driving and 9T driven sprockets. Info for 18x7 rubber tire drive wheel. If using 5.5"center rib tire or steel wheel drive, multiply above spacing by 0.9.

From the 50 unit OM: With a 24 cell plate, use 18T driving and 11T driven sprockets for 6.8" seed spacing. For 7.2" spacing, you can use 14T driving and 9T driven or 17T driving and 11T driven sprockets. Same multiplication factor as the 74 units if using the 5.5" tire or steel wheel instead of the 18x7" rubber tire.

Don't forget to factor in germination rate. dave