Happijac 4500 Fun

[brucekr]

Hello, new to the forum.

I recently bought a used Bigfoot camper and when we were loading it in my pickup, I could tell the jacks needed some TLC. I watched this video for the teardown and reassemble of the units:
https://www.youtube.com/watch?v=k9wKi0kO19o&t=188s

But at about 2:40 into that video, my issues arise. I can't get the motor assembly off of the jack. I've tapped on it with a hammer like the video shows...nada. I'm a little leary of breaking it, so I grabbed a section of 2x4 and a rubber mallet and I just can't seem to separate the motor housing. Any ideas on that it could be? I have of course removed the 2 screws holding it in.
In the process, I did have a slight miss and nicked a tiny piece, but think it should be ok with a little sealer.

Thanks in advance!

[brucekr]

Appreciate the help and the links.

I got the motor off, but ended up breaking the housing and had to order a replacement from Lippert. Mine had the drive coupling release lever, but the hardware didn't match any of the tutorials that I've watched or read. There was no spring and the drive coupler was different, and it was nearly impossible to disengage the motor for manual cranking. And ultimately, I gave up trying to get the bottom gear off the shaft, so I couldn't directly grease the threaded shaft. But I can run the jack from stop to stop with my drill without any hangups, so I'll address this in the future I guess.

Just FYI, here are the part numbers and prices as of today from Happijac (Lippert).

182923 Housing (top and bottom with seal and screws) $59.95
182517 The drive coupling hardware kit (spring, etc) $8.95

The phone number I called to order the parts was 801.544.2585
I'll say that they were easy to deal with and had I called an hour earlier, my parts would've shipped that day. As it was, they shipped the next day, and in 2021 that's much appreciated.

[bigfootford]

The motor and gear box should come off with some gentle tapping...If not that would be strange. I wonder if someone put the motor/gear box back on with some sealer..uggg.
My BF is 21 years old now. My jacks have been used 100's of times. I have serviced them 2 times, only the fronts. One broke the shaft keeper and was binding up. I ended up buying 2 new 4500's a couple of years ago. I have only serviced the rears one time.

Here is the link to HJ repairs....

https://www.rv.net/forum/index.cfm/fuseaction/thread/tid/22881036.cfm

Jim

[TxGearhead]

Search this forum for Happi Jac lubrication.
I found it. It's a "sticky" in Truck Camper University.

[JimK-NY]

You are supposed to periodically run the jacks up and down a couple of times with full extension to spread out the lube. I would try that first.

Once you pull the bolt the motor should come off easily. If not, I suppose it could be corroded. More likely someone used some sort of sealant. Anyway I would start with penetrating oil.

[brucekr]

By TLC, I meant that the front driver side jack at first wouldn't even budge with the motor, so I had to manually crank it at first. Then at different points throughout, the motor was just more labored than the others. So I was going to clean and grease the ball screw and thread and potentially send the motor in

[JimK-NY]

Just two quick comments---

First what do you mean about the jacks needing some TLC? What is wrong?

Second, disassembly and services of the jacks is not a simple matter. If you are having issues just removing the motors, you are only on the first and simplest part of a long journey.

I think I was lucky with mine. One froze and parts broke. It was easy and not especially expensive to replace the jack. I even bought a spare.