JD 790 Battery,Maintainer & Block Heater Install

   / JD 790 Battery,Maintainer & Block Heater Install #1  

Trails2004

Gold Member
Joined
Nov 29, 2009
Messages
297
Location
Outside
Tractor
2009 JD 3520
As a one of the new guys on the block, I wanted to share some recent modifactions to my "new to me" 2003 790.

The first step was to add a block heater. I read many threads on the this forum before I tackled this project. I read the pro's and cons of the "katz" in line type heater and a "block type" heater. I chose a block type heater for my 790,as this type seems to warm the engine and all fluids in the block.

I went to the JD store in a neighboring community, I purchased a thread in type "block heater", I was also sold an adapter- which I later returned for credit. This model of engine does not require the adapter.

I drained the coolant from the radiator, I then proceeded to remove a treaded 1/2" plug from the left hand side of the engine. This did take a little "umph" 2- 12" 1/2" drive extensions and a 1/2" breaker bar. Just when you think the plug will not move - it slowly loosens-- yeah! Remember to place a container below the area with the plug- because you will have 1-2 quarts of coolant that will drain from your engine block.

I used "Rector" seal on the threads of the "block heater plug", you will need a 1 3/8" socket to install the plug-this is a brass plug so you do not need to "drive it home". I also used a large set of "water pump" pliers to help tighten the plug. This is rather akward without removing other components on the engine ( exhaust, starter etc.) But it can be done.

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Next I noticed the battery was a 2002 vintage Napa Professional-The battery must have been laying around at the previuos owners house, becuase the tractor is a 2003 model year- or it was left on hand at the local Napa store- which is more likely the case.

Again after reading many posts on this forum I chose a "Red Top" Optima battery. I debated on this purchase, as I have two of Sears Platinum "AGM's" in my pickup and I really like them. I also have heard of issues with the Optima batteries, but I have had one in my boat for 5 years- so I chose to give the "Red Top" a try. They are not inexpensive! While I was removing the old battery I noticed alot of crud in the bottom of the battery pan area- so I cleaned to the best of my ability- sealed with a primer and re painted with JD green.

Note I did not remove my 419 FEL- I found ample acess through the top, after I removed the air cleaner housing.

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Also at this time I installed an onboard "battery maintainer" which will help keep the new "Red Top" at a full charge. I routed an extension cord around the air intake (see white nylon wire ties in the 3rd photo below) fuel tank and dropped the plug near the block heater for easy connections.

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The cord on the left is the block heater and on the right is the battery maintainer. I use a three way plug to make the connection.

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I also use a "wireless remote" power center for the block heater. I can press a button on the remote from the house and this will turn on the block heater. I leave the battery maintainer on at all times. The block heater will warm up the block and coolant within less than an hour.

Parts List:
JD Block Heater " thread in type"
Optima "Red Top" RED 34/78 CA 1000 amps
Schumacher Model SE-1-12S Automatic Battery Charger/ Maintainer
Carlon "wireless remote" Power Center Model HW2190L

Thanks for reading!
 
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   / JD 790 Battery,Maintainer & Block Heater Install #2  
Nice write-up!

thanks for sharing.:D
 
   / JD 790 Battery,Maintainer & Block Heater Install #3  
Thanks for sharing your project with your setup you should be well prepared. I would have used the Die Hard Platunum battery though. Being a boater I have read of too many problems with Optima batteries. Hope that Optima has their problems fixed by now.
 
   / JD 790 Battery,Maintainer & Block Heater Install
  • Thread Starter
#4  
.....I would have used the Die Hard Platunum battery though. Being a boater I have read of too many problems with Optima batteries..... .


Thank you for your comments- I do have a three year- non pro rated warranty. The Sears outlet store is 25 miles oneway from my home- they do not stock batteries- so I was kinda in a tight spot- if I wanted to fix the tractor pre-christmas

So if the "Red Top" dies I hope it is within 36 months and not 37 or 38 months ;) The later is my luck
 
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   / JD 790 Battery,Maintainer & Block Heater Install #5  
Nice descriptions and pictures! looks like the battery maintainer might be in the way of the air filter housing lid when it comes time to change the air filter.... But very nice job on the installs though:D
 
   / JD 790 Battery,Maintainer & Block Heater Install
  • Thread Starter
#6  
.... looks like the battery maintainer might be in the way of the air filter housing lid when it comes time to change the air filter...

Actually just enough room to remove the air filter-(the picture really doesnt show the correct distance between the maintainer and the air filter cover)-it fits like a glove- I love it when a plan comes through- It doenst always happen that way for me :D

Even if it doesnt fit just right it is very easy to loosen the 12mm bolt on the filter center support band and slide the housing back a touch.

Thanks for your comments- perhaps this will help someone else through the process of adding a heater, maintainer or a battery.

I'm certain their are a ton folks out there that are a lot smarter than I'am and can do a better job on the install! :D :D
 
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   / JD 790 Battery,Maintainer & Block Heater Install #7  
I like the remote!!!
 
   / JD 790 Battery,Maintainer & Block Heater Install
  • Thread Starter
#8  
I like the remote!!!

Yeah that is sweet- I did see a thermostatically controlled plug ( that is used on heat tape) but it turns on at 38 F and shuts off at 50F - In my neck of the woods it would be on all winter! :D
 
   / JD 790 Battery,Maintainer & Block Heater Install #9  
I liked the remote idea too, could you post more info on it?

I am also curious why you thought you would need a charge maintainer with an AGM battery. I have found that while I do need to recharge my boat batteries that once fully charged they will retain the charge for 6 months no problem.
 
   / JD 790 Battery,Maintainer & Block Heater Install #10  
I too have done the install on the 790 block heater....and your description on "how-to" was well stated. It's kind of a bear to get that plug out....and in without special tools. Nice to see such a good write up.....with pictures!!
 
 
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