Help! One of my jacks won't retract or extend!

[RamblinAnne]

So I've had issues with my happijacs since day 1. It's partially my own fault - I never properly cared for them. One in particular always seizes up and I have to bust out the manual crank. It's a pain but it works. Except for today. When going to raise the camper up so that I could load it on to the truck, even the manual crank failed. I was going at it and I felt the gear slip and now it just spins and spins and does not lower down or raise up. What do I do??

I took the motor off but can't really get to the actual jack mechanism without taking the whole jack off the the camper. Which I can't do since the camper is not supported by the truck. (I do have it supported by some homemade saw horses - 2 EAZlift telescoping jacks with some 2x4s going across to support).

Most importantly, I want to get the camper back on the truck ASAP. I will feel a lot more comfortable working on the jacks once the camper is on the truck. My biggest fear is being stuck somewhere and not being able to take my home with me so first things first, I gotta get the camper on the truck. But how do I do this with only 3 working jacks?? (It's the front right jack that isn't working).

Any prompt advice would be much appreciated! If you can't tell, I'm slightly panicked by the idea that the two pieces of my home won't come together. Thanks everyone!

[RamblinAnne]

Well Jim, it's true. You must have a very big bootied camper because no matter what I did, I couldn't get the camper to stand on 2 rears and 1 front jack. The weight kept shifting forward.

I was able to get the camper on the truck (yay!). It was panic-inducing but I did it. I didn't have a hi-lift jack (though I did just order one along with two new 4800 happijacs to replace the two fronts) so I used a car jack and a long piece of lumber to jack up that front corner. Got the bad jack off. Was going to swap with a rear but I REEEALLY did not like the idea of the camper being on 3 jacks. So I fiddled with the jack gears a bit and was able to get them to turn, not with the manual crank (that pin had broke) but I used a ratchet coming in from the top. I wasn't able to lift it or anything with this method but once I jacked it up to the right height using the 3 good jacks + the car jack, I was able to lower the leg down enough so that it was at the right height. Then removed the car jack so that I could back my truck in (dually would have hit the jack). Once the truck was backed in to the right spot, I put the car jack + beam back in place and retracted the bad jack leg with ratchet method and slowly lowered with the 3 good jacks + car jack.

Woof! What a process but I got it on there. I feel SO much better. So yes, I just ordered two new 4800s for the front + 2 motors. Hoping the rears will last me awhile longer but we will see.

Thanks to everyone for all the quick replies. You guys always save the day.

[JimK-NY]

You don't need to strain your jack to hold either the front or back of the camper with one jack. My jacks are rated at close to 3000# each and the entire camper is about 4000#. It is not physically possible or certainly feasible to exceed the jack capacity. That would mean almost the entire weight of the camper on one jack. All that is needed is a jack capacity that will support about half of the camper's weight. Nor is it necessary to jack up the camper at some extreme angle that will strain the jacks. Just a few inches is all that is needed.

Anyway this whole argument is silly. There should be no problem putting some pallets or other supports under the camper so that the bad jack can be disengaged and replaced. In fact it is not necessary to have any of the weight on any of the jacks. The entire weight of the camper can be supported by supports under the floor of the camper.

[Bedlam]

With the camper sloped to the rear you can hold it up with only one front jack. It is a lot of strain on that jack due to the angle and weight and that single jack may not be able to raise the camper any higher.

In Anne's case, she needs to shore up the corner with the bad jack and remove it. If she needs to move before getting a replacement or fixing this one, shoring up a back corner and moving a rear jack to the front would get her on her way. There is no use further speculating until Anne responds with her course or action.

[Grit_dog]

I won’t profess to have been around a great number of campers and if it works for you Jim then your camper is an anomaly in that the center of gravity is behind center between the front and rear jacks. (Or at least beyond the line that would bisect the camper on the applicable front and opposite rear jacks that are the pivot of the teeter totter in your scenario.
It has to be if you have lifted a front Jack with no other support.
That is not how most? campers are built though. Yours has to be very rear weight biased.

Regardless, to profess that this is a foregone conclusion to someone who doesn’t even know how to support, remove or fix a Jack is really dangerous advice.

[JimK-NY]

You guys have great logic, but I can still tell you in spite of the logic, I have no problem supporting my camper with a single front jack and two rear jacks.

My camper is a Northstar Igloo with an extended cab to accommodate a N-S orientation for a full sized Queen mattress. If I jack it up and look at it from the side, it appears in danger of tipping over frontwards. That is not at all the case. In fact it can be used supported by the jacks and that use can include at least a couple of heavy people in the overhang.

The camper COG is just not as far forward as it appears. Few of us have scales but there are a couple of ways to determine this. First at least for my Northstar the manufacturer has specified the COG. It is only a little bit forward of the center of the floor area. Second you can weigh your truck and then your truck with the camper. My camper is about 4000# fully loaded. All but about 100# sits on the rear axle of the truck. The COG is only inches in front of the rear axle and again that is close to the center of the floor.

There is another factor that helps. Proper use of jacks means keeping the nose of the camper pointed upwards by a couple of inches or so. That shifts the COG further to the back. In fact I would guess it takes only a few inches of lift to shift the COG so that more than half the weight falls on the rear jacks. It is not necessary to shift more than half the weight to the rear. You can end up with say 55% of the weight on the front jacks and even amounts of the remaining weight on each of the rear jacks. Then lower one of the rear jacks. That will again shift the COG and will tilt the camper to the point where the diagonal front jack will be off the ground.

All I can say further, is try this for yourself. It will work, or at least it does with my Northstar.

[wnjj]

JimK-NY wrote:
The only tinkering needed is to adjust the jack height so that the broken jack does not carry any weight. I can do that easily using the bubble levels I added. It does not matter that the COG is forward of center. The good front jack can be extended to keep the front higher than the rear. All I can tell you in addition is that you can try this for yourself. It is real easy to do and you can easily take the pressure off of any one jack by adjusting the others.

The COG is all that matters. It’s basic physics (statics) that when an object’s COG is outside of its contact points with the ground it will tip over. It’s really that simple.

So if you take a camper where the COG is forward of center, you cannot form a triangle with both rear jacks and only one front that includes the COG inside the triangle.

If I tinker with the jacks and raise a rear one, it lifts off the floor. If I raise a front one, the opposite rear one lifts off the floor. Being careful and deliberate doesn’t change the physics. The diagonal becomes the teeter totter support and the chunky kid is always sitting on the front. A front jack cannot be made to not carry any weight.

[whazoo]

It is correct that you can’t lift with three jacks, 1 front and 2 rear. You can though lift with 2 front and 1 rear. Like someone said it used to be 3 jacks tho they were not even front to back, one was about middle on one side. Huh? So while on the supports, remove the bad front and replace with a good rear. Walla, good to go until to you fix the now rear jack. A big yes to putting the bad jack on the back just in case it does tip, a little leg is better than none. And yes, probably a shear pin on the gear or the mechanism with the lever that transfers from manuel to auto, it’s plastic. I rebuilt mine last year but sitting here now the memory is a little foggy. Also, let a lot of air out of your rear tires so you don’t have to lift the camper as high. Maybe down to 15-20 lbs.

[JimK-NY]

Some people are just plain hard headed. No photo would convince them. They would blame Photoshop. All you need to do is start with a level camper on all 4 jacks. Retract any jack and the jack on the diagonal will be off the ground. I would not expect this to be stable. I would not get in the camper and walk around. I would even be concerned about a strong wind. With the camper on 3 jacks, you can prop it up with a stack of pallets for example and then remove and replace the bad jack.

[Grit_dog]

I had a rather tongue in cheek response queued up, but instead.
Anne, please do not try this trick at home.....at least until JimK posts a pic of his TC balanced diagonally with a front leg in the air.

[AnEv942]

The TriPod jack mentioned, might be something you could rent or borrow 'possibly' from local RV shop. Rental yard might have something.

Atwood jacks are no longer available, parts increasingly hard to find, no longer made.
Previous Happijac jack models also no longer made with the introduction of the new 4820. Some parts still available.
The new leg, Lippert #736515 (new HJ owners) 'I think', but I'd verify, interchangeable with existing motor, depends on retailers Panther says it will, Tweetys only list new motor as fitting- same part?
Other than trying to fix, replacing just the leg assembly and install existing motor on it would be the least expensive and most expedient. Though Id plan to replace other front at minimum-at least sometime in the near future.
https://tweetys.com/lippert-736515-clutchless-current-sensing-4820-acme-hd-screw-jack-2-800-lbs-whit...
https://pantherrvproducts.com/happijac-4820-736515-rv-electric-truck-camper-loading-jack-leg-only/

[JimK-NY]

wnjj wrote:

JimK-NY wrote:

Grit dog wrote:
OMG, that’s the advice that is sooo weird about this site......
OP has a bad FRONT jack and the camper won’t stand on 1 front jack period end of story unless ya seriously ballasted in the rear.

Of course you can. Slightly raise the good front jack and the back jack on the other side. Lower the other rear jack. With a little tinkering the camper will be supported by the 3 good jacks and all the pressure will be off of the bad jack.

By tinkering do you mean piling a bunch of weight on the opposite rear corner or tethering the jack to the ground? The COG of a camper is much closer to the front than the rear jacks. Simply put, this means it will always tip forward if 2 diagonally opposite jacks are extended further than the other 2.

The only tinkering needed is to adjust the jack height so that the broken jack does not carry any weight. I can do that easily using the bubble levels I added. It does not matter that the COG is forward of center. The good front jack can be extended to keep the front higher than the rear. All I can tell you in addition is that you can try this for yourself. It is real easy to do and you can easily take the pressure off of any one jack by adjusting the others.

[bb_94401]

The Camo eze-lifts have minimum height of 19" to 47" and fine adjustment to 61". 5000 LBS support, but I don't know how much you could actually lift without galling or stripping the threads. Good temporary support to remove and repair the jack. Maybe not enough to lift it to load into the truck and fix the jack later. So you may have to do the two diagonal leg slightly higher trick to be able to lift it with the eze-lift (I'd put anti sieze on the adjuster thread).

If you really want to lift it high enough to fit into your truck I'd call Rieco Titan and have them drop ship a single Tripod Camper Jack . It has a minimum height of 38" and max of 60" and can lift 2,000 lbs. Only issue is the height you'd need for your 4x4 DRW truck, may need a block or two. One other consideration is that with the dually, you'd need to make sure that the tripod legs were capable of being oriented so you could avoid hitting them with the tires when loading.


Click For Full-Size Image.

[wnjj]

JimK-NY wrote:

Grit dog wrote:
OMG, that’s the advice that is sooo weird about this site......
OP has a bad FRONT jack and the camper won’t stand on 1 front jack period end of story unless ya seriously ballasted in the rear.

Of course you can. Slightly raise the good front jack and the back jack on the other side. Lower the other rear jack. With a little tinkering the camper will be supported by the 3 good jacks and all the pressure will be off of the bad jack.

By tinkering do you mean piling a bunch of weight on the opposite rear corner or tethering the jack to the ground? The COG of a camper is much closer to the front than the rear jacks. Simply put, this means it will always tip forward if 2 diagonally opposite jacks are extended further than the other 2.

[JimK-NY]

Grit dog wrote:
OMG, that’s the advice that is sooo weird about this site......
OP has a bad FRONT jack and the camper won’t stand on 1 front jack period end of story unless ya seriously ballasted in the rear.

Of course you can. Slightly raise the good front jack and the back jack on the other side. Lower the other rear jack. With a little tinkering the camper will be supported by the 3 good jacks and all the pressure will be off of the bad jack.