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What is this?

February 13, 2013, 07:17:03 am

 I'm sorry but this is the first of a lot of ??'s that I have . A little history,Ft made in June 1984 Vin #10t8ma31e1023423, Type FTX8523613600red c and v-917-2. I brought this home Feb. 2012, It has been fun trying to repair all of the things that I have found that do not work.I have a pic. and this thing mounts on the rt rear frame rail and has two black (-) cables and two red (+) positive, One black cable has been removed and the red cables also. They have taken one black and one red and bolted then together. What does this thing do and what will be improved when replaced? The other red cables is not hooked up to any thing..  Sid

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Re: What is this?

Reply #1 – February 13, 2013, 07:49:31 am

That looks like your isolator.  It should be wired the alternator to center stud house batteries on left and start on right. Might suggest a new one.  Looks to me the engine is only charging one side not both as it should. Nt here is also a spliter box in my coach from the start battery to the starter and the isolator.  Those can go bad too. 

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Re: What is this?

Reply #2 – February 13, 2013, 07:50:56 am

Ask away.  Your rig is a bit older but we should be able to help. If not call James Triana at the factory with your unit number and he can help out as well.

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Re: What is this?

Reply #3 – February 13, 2013, 11:29:19 am

Yup,

As John says it is your isolator.

Here is a link to a YouTube video explaining what it is and does.

Why do I need a Battery Isolator?

Keith

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Re: What is this?

Reply #4 – February 13, 2013, 07:50:08 pm

Keith, Thanks for the video, that was great, makes it easy to understand

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Re: What is this?

Reply #5 – February 14, 2013, 07:30:33 am

Kieth, Thanks for video. Is there any place to get a deal on this part? or is it best to get one from Mike at fT? I 'm thinking it is kinda like a junction box? with a brain....

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Re: What is this?

Reply #6 – February 14, 2013, 11:41:26 am

Just a quick search on Google and I found an isolator rated at 140 amps here:http://www.summitracing.com/parts/pwm-903?seid=google&gclid=CPCyh_ydtrUCFUVN4AodIj8AJA

Don't know if it an exact fit but may suit your needs for a bit over a hundred dollars. Did not do an extensive search this is just the first hing that came up. Usually NAC prices are a bit more than what you can purchase on line.

Roland

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Re: What is this?

Reply #7 – February 14, 2013, 05:31:32 pm

Is there a way , or a number on the old one that would tell how many amps are needed ? Do they come in different shapes and sizes?

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Re: What is this?

Reply #8 – February 14, 2013, 05:44:54 pm

They should be big enough to handle the output of your alternator. Many RV owners have mixed up the wires when replacing the isolator. They have a band with the codes but may no longer be readable so put your own tags on before removing wires. Check the big ones with the fins on this ebay page: 200 amp isolator | eBay

Isolator is probably located about a foot in front of your driver's side rear tires at the top of the metal panel.

Pierce

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Re: What is this?

Reply #9 – February 14, 2013, 06:33:24 pm

Amps on isolator should be at least or more than amp output of engine alternator.

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