Toby Stockman 70 #1 Posted July 24 i am looking for the wiring harness part number for an 87 312-8 looking in the manual cant seem to find the # for the whole harness if you know the # please let me know Thanks! Share this post Link to post Share on other sites
gwest_ca-(File Mod) 11,072 #2 Posted July 25 https://www.partstree.com/models/21-12k804-312-8-toro-garden-tractor-1987/electrical-system-9/ https://www.partstree.com/models/21-12k804-312-8-toro-garden-tractor-1987/electrical-system-8/ https://www.partstree.com/models/21-12k804-312-8-toro-garden-tractor-1987/electrical-system-7/ Share this post Link to post Share on other sites
953 nut 55,394 #3 Posted July 25 The likelihood of finding a NOS 37 year old wiring harness is very slim so a part number probably wouldn't be very helpful. You could pay $ 162 for the idiot light harness which is outrageous in my opinion, but it is your money. We can help you go through the process of rewiring the 312-8 if you want to do it yourself. It isn't as difficult as you may think. This file shows each system and will be helpful to you. Share this post Link to post Share on other sites
Toby Stockman 70 #4 Posted July 25 Thanks i have located the main harness part # the reason i ask is i see there are a couple NOS wiring harnesses that just popped up on ebay and looked just like it. figured if it was correct just to replace it while im restoring the tractor and have everything apart. Share this post Link to post Share on other sites
Sport 0 #5 Posted August 13 Hi, I have an 87 312-8. I used to be in the Yahoo groups, but didn't keep up. Just now joined up on this group as I found some details about the indicator board. I've been playing around with a redesign of the indicator board using bright red LEDs. I am now retired, but my profession was electronics. I had designed circuits and boards as part of my job for over 30 years. I would like to offer my learning to anyone who cares. I could probably help owners make repairs, and would provide any information I can to anyone who wants it. I downloaded the demystification guide many years ago, and I have the original manual that came with the tractor. There are errors in the demystification guide, and in the manual on the electrical wiring diagrams. The wiring to the test switch is wrong in the manual. The oil float switch operation and how it prevents start is incorrect in the demystification guide. I can provide the corrected version if any one cares. I can also provide a schematic diagram of the indicator board. I've seen comments stating a regulator must be present on the board to accommodate the SN54LS86. The AJ is because it's a ceramic package/ and extended temperature range specs, but there is no regulator on the board. The voltage to the LS86 is normally too high, but it seems to hold up for some reason. Probably when connected in the tractor, the 470 ohm resistor drops enough to get it closer to 5V. I submit the original indicator board schematic, and another with a few added details helping show the oil test switch here. Is there a documents section? Thanks,WheelHorseIndicatorBoard.pdf SportIndicator Board.pdf Share this post Link to post Share on other sites