Electric Tongue Jack

[Kmikesell]

I am planning on putting a new electric tongue jack on my 2016 2720. I am replacing the old crank unit and I have a couple of questions for those who may be in the know.

1. How do you wire around the swing-away hitch?
2. Where should you wire the positive side of the connection?

 

[Shane826]

Just wire along the pivot side of the swing hitch and leave some slack to allow range of motion. I would wire directly to the battery if you don’t already have a lead for a power jack. Don’t forget the fuse on the positive lead within 6” of the battery. If your jack doesn’t have a negative lead and grounds through the body of the jack, create a ground strap to jumper from the A-frame to the main chassis.

 

[Kmikesell]

Just wire along the pivot side of the swing hitch and leave some slack to allow range of motion. I would wire directly to the battery if you don’t already have a lead for a power jack. Don’t forget the fuse on the positive lead within 6” of the battery. If your jack doesn’t have a negative lead and grounds through the body of the jack, create a ground strap to jumper from the A-frame to the main chassis.

Can you define a "ground strap" and couldn't I just run a positive and negative lead back to the battery?

 

[Kidkraz]

I just placed a ground on the jack, I made sure there was bare metal under that bolt hole. I also left about 3-5" of slack at the hinge side of my tongue. There is the ground block on the street side if the tongue after the swing hitch, next to my batteries.
Sorry for the spider webs.

 

[Bill-TMO]

If you have a battery on the tongue, then running two wires directly from the jack to the battery is OK, because both wires would be short. But in a 2720 SL, the battery is a long ways away, and you need long wires to reach it. And long wires cause a bit of voltage drop because of their resistance. You don't have a lot of choice about running a long wire to the positive side of the battery. But you can eliminate the long wire to the negative side of the battery by using the trailer frame as the connection. The frame, being a big hunk of steel, has much less resistance than a wire, and hence less voltage drop. And less voltage drop means more voltage available to run the jack. The only challenge to using the frame is that you have to bridge the gap between the jack and the actual frame of the trailer - the swing point of the swing tongue is a lousy conductor.

Besides, it saves the cost of 25 feet of wire!

Bill

 

[Shane826]

Can you define a "ground strap" and couldn't I just run a positive and negative lead back to the battery?

Ground strap- Just a chunk of battery cable or heavy electrical wire connected from the A-frame to the main chassis.

 

[Kmikesell]

If you have a battery on the tongue, then running two wires directly from the jack to the battery is OK, because both wires would be short. But in a 2720 SL, the battery is a long ways away, and you need long wires to reach it. And long wires cause a bit of voltage drop because of their resistance. You don't have a lot of choice about running a long wire to the positive side of the battery. But you can eliminate the long wire to the negative side of the battery by using the trailer frame as the connection. The frame, being a big hunk of steel, has much less resistance than a wire, and hence less voltage drop. And less voltage drop means more voltage available to run the jack. The only challenge to using the frame is that you have to bridge the gap between the jack and the actual frame of the trailer - the swing point of the swing tongue is a lousy conductor.

Besides, it saves the cost of 25 feet of wire!

Bill

Yeah my batteries ARE in the back. I like the idea of a shorter ground and run the positive to the back. Is there no poss connection closer...say the fridge?

 

[Kidkraz]

Any chance the radio connection might work for this?

 

[goldwingj1]

Electric jack

We created a 2-wire harnes & tapped into the wiring going to our 7-pin plug; that way can ensure we always have power when we need it.

 

[Kmikesell]

We created a 2-wire harnes & tapped into the wiring going to our 7-pin plug; that way can ensure we always have power when we need it.

I though about this option as well!

 

[Bill-TMO]

Maybe ...

Any chance the radio connection might work for this?

TM tended to change the wiring fairly often over the years. The diagram I am looking at shows the radio circuit fused at 20 amps - and shared with the refrigerator, a power hog on DC. So if your TM matches this diagram, it might work - or you might pop the fuse if you crank the jack while the refrig is running.

The radio itself is a low-power device, so it could be connected into almost any of the power distribution circuits, including any of the low power ones. So before connecting the jack into the radio circuit, I would suggest checking which fuse powers it.

Bill

 

[Kmikesell]

TM tended to change the wiring fairly often over the years. The diagram I am looking at shows the radio circuit fused at 20 amps - and shared with the refrigerator, a power hog on DC. So if your TM matches this diagram, it might work - or you might pop the fuse if you crank the jack while the refrig is running.

The radio itself is a low-power device, so it could be connected into almost any of the power distribution circuits, including any of the low power ones. So before connecting the jack into the radio circuit, I would suggest checking which fuse powers it.

Bill

Great advice...thnaks