Replacing tongue jack

[mudman2]

Hi all
I’m replacing my electric tongue jack after not raising it and bending the drop pole. Anyway the existing has one red power line. I guess the unit is grounded to the frame. The new one has a 7pin plug already attached. I want to put a 7 pin receptacle on trailer. Does the existing red wire go to the black power terminal than a ground wire from the receptacle to the frame?

[Bama Rambler]

Can you post the make and model of it?
Yes you'll wire the existing Red wire to terminal 4 and run a ground wire from terminal 1 to a good place on the frame.

Here's a diagram of how to wire a 7-way.

[Mr. Dan]

Originally Posted by Bama Rambler

Can you post the make and model of it?
Yes you'll wire the existing Red wire to terminal 4 and run a ground wire from terminal 1 to a good place on the frame.

Here's a diagram of how to wire a 7-way.

Excuse my ignorance, Rambler... but why would a new tongue jack have a 7-plug on it?

[emm-dee]

Originally Posted by Mr. Dan

Excuse my ignorance, Rambler... but why would a new tongue jack have a 7-plug on it?

I was going to ask the same thing. The power tongue jack only needs a single electrical line which is usually run direct to the battery (with an in-line fuse). The 7-pin has nothing to do with the jack.

[5picker]

Some replacement electric jacks are made with a 7 pin plug/cable so they can be a replacement for a non-powered jack.

All you have to do is plug the plug into the tow vehicle's 7 pin socket and hit the switch. No other wiring needed.

Not really sure why the OP bought this style since they already had an electric jack. Maybe the only one available locally?

[mudman2]

Its a big horn 3500 electric a frame jack. I guess put the 7 pin plug for people who have manual jacks without electricity immediately present. I
People can than plug it into their tow vehicle to operate it. I figured I’ll keep it on and just put a receptacle on the trailer. I guess it’s also a bonus if u find your trailer battery dead. I purchased this unit for its water resistant properties.

[emm-dee]

Originally Posted by mudman2

Its a big horn 3500 electric a frame jack. I guess put the 7 pin plug for people who have manual jacks without electricity immediately present. I
People can than plug it into their tow vehicle to operate it. I figured I’ll keep it on and just put a receptacle on the trailer. I guess it’s also a bonus if u find your trailer battery dead. I purchased this unit for its water resistant properties.

Thanks for the added info. Looked up that model and it appears, as you mention, the 7 pin is there to get power from the tow vehicle. Personally, I'd replace it with the single line to the trailer battery. With the 7-pin system every time you needed to use the jack you would have to back up the TV and, depending on the model, leave the ignition on in order to have power available.

Not sure how many amps that jack uses but it is possible to overload the TV circuit. My previous TH had a Husky jack with a 30 amp fuse. The TV fuse for the 7-pin continuous power line was 20 amps.

[Bama Rambler]

Originally Posted by Mr. Dan

Excuse my ignorance, Rambler... but why would a new tongue jack have a 7-plug on it?

The question has already been answered, so I won't repeat what's already been posted.

I thought about suggesting they remove the 7-way and just wiring it up direct, but than I thought, what if there was ever a need to move the RV and the battery was completely dead or removed. It would be really handy to just plug the jack into a tow vehicle and raise or lower it. So it may not be a bad idea to just install a 7-way receptacle.

[Mr. Dan]

Originally Posted by Bama Rambler

The question has already been answered, so I won't repeat what's already been posted.

I thought about suggesting they remove the 7-way and just wiring it up direct, but than I thought, what if there was ever a need to move the RV and the battery was completely dead or removed. It would be really handy to just plug the jack into a tow vehicle and raise or lower it. So it may not be a bad idea to just install a 7-way receptacle.

All part of my continuing education........ "I've never seen ner heard tell of such!" but I've also never dealt with an A frame trailer. Oh, well.

[mudman2]

Originally Posted by Mr. Dan

All part of my continuing education........ "I've never seen ner heard tell of such!" but I've also never dealt with an A frame trailer. Oh, well.

The a frame was my previous trailer. I have to change the photo

[Chuck_S]

If there's cord with a 7-pole plug on the end the jack is designed for utility or boat trailers which lack an on-board battery. Plug it into the truck when you need to.

But since your camper has battery the long cord is an unnecessary complication as all ya need is one wire to the on-board battery.

-- Chuck

[CincyGus]

Best of both worlds is buy a female 7 pole plug and install it on your trailer. them wire it as Bama Rambler describes and you can leave the jack plugged in on the trailer but still have the flexibility to plug into your truck should your trailer battery ever dies.

[babock]

My Ford F-150 has a 14 gauge wire that goes to the power pin of the 7 pin connector. A jack would not do well with that size wire.