On this board, one will find different ways to mount a camper to a chassis. I'm not an expert on any of them and can't participate in the details of any mount. This thread is simply our journey to fix a problem. If you ask me any questions about anything other than what we've done, I won't be able to answer. Questions about breaking the frame are outside my expertise. Perhaps other discussions can simply reference this thread as one way to solve a specific problem.
We bought a well known 2003 Fuso camper a year ago. This thread is about our journey to remount the camper on the chassis. Mounting the camper to the chassis was originally accomplished with C channel steel and hard wood 4" square posts, secured with 8 U bolts. This is a direct fixed mount allowing no pivot. Over time the wood posts moved and partially collapsed, causing the camper to move forward and down, especially on the passenger side.
Our first stage to correct this problem was to return to the Unicell manufacturer in Toronto. They easily lifted the camper, squared it in all directions with the frame, and replaced the square wood posts with C channel steel and one 2x4 hard wood board. Thinking all was well we returned to Arizona.
Then I noticed the bottom legs of the bottom Fuso C channel steel were bending upward under the U bolt cross plates and the top legs of the top C channel steel were bending downward under the top curve of the U bolt. The U bolt cross plates were also bending upward. Unicell stated the U bolts were to be torqued to 75ftlb. This was not possible because all the U bolts had shifted toward the inside of the frame. The outside leg of the U bolt was against the frame and could be torqued. The inside leg of the U bolt and cross plate stuck out over 2" inside the frame. This meant that when I tried to torque the inside leg, the U bolt bent downward and the cross plate bent upward, not allowing greater than 40ftlb pressure. So, one leg tight and one leg loose on the U bolts. I had 1/2" thick flat cross plates made. They started to bend upward like the prior thinner plates.
Examining this situation more closely, the new hard wood 2x4 also protruded further to the inside, preventing the U bolts to be centered.
Over time I'm guessing various attempts to torque the U bolts resulted in bending the C channel steel and the U bolts.
I had longer plate steel welded under the bottom C channel for strength- didn't solve the problem.
It was futile to straighten the C channel. A frame/alignment shop just didn't want to do it. They didn't want to give up insured car wreck time to fix my small problem.
I had 1/4" thick plates cut and welded inside the C channel under the U bolts to reinforce the upper and lower channels, turning them into "box" frames. Some of these plates had to go through the grinder to fit the bent curves of the C channel.
I chiseled out the wood to allow the inside leg of the U bolt get closer to the inside and center on the frame.
Next, some of the U bolts wouldn't stay centered during the torque. They would shift to the inside of the frame. Instead of having a straight across top of the U bolt, some had become angled downward to the inside. I had square 1" steel blocks welded to the upper outside C channel to keep the U bolt centered during the torque. This allowed the U bolts to extend 1" to the outside and inside, centering the bolts.
Last I had thick L angle steel cut to replace the flat U bolt cross plates. These didn't bend.
These were the steps to allow me to torque all U bolts to 75ftlbs:
remount body
convert C to box channel frame members
center the U bolts
use L angle U bolt cross plates
Before and after pictures to follow
We bought a well known 2003 Fuso camper a year ago. This thread is about our journey to remount the camper on the chassis. Mounting the camper to the chassis was originally accomplished with C channel steel and hard wood 4" square posts, secured with 8 U bolts. This is a direct fixed mount allowing no pivot. Over time the wood posts moved and partially collapsed, causing the camper to move forward and down, especially on the passenger side.
Our first stage to correct this problem was to return to the Unicell manufacturer in Toronto. They easily lifted the camper, squared it in all directions with the frame, and replaced the square wood posts with C channel steel and one 2x4 hard wood board. Thinking all was well we returned to Arizona.
Then I noticed the bottom legs of the bottom Fuso C channel steel were bending upward under the U bolt cross plates and the top legs of the top C channel steel were bending downward under the top curve of the U bolt. The U bolt cross plates were also bending upward. Unicell stated the U bolts were to be torqued to 75ftlb. This was not possible because all the U bolts had shifted toward the inside of the frame. The outside leg of the U bolt was against the frame and could be torqued. The inside leg of the U bolt and cross plate stuck out over 2" inside the frame. This meant that when I tried to torque the inside leg, the U bolt bent downward and the cross plate bent upward, not allowing greater than 40ftlb pressure. So, one leg tight and one leg loose on the U bolts. I had 1/2" thick flat cross plates made. They started to bend upward like the prior thinner plates.
Examining this situation more closely, the new hard wood 2x4 also protruded further to the inside, preventing the U bolts to be centered.
Over time I'm guessing various attempts to torque the U bolts resulted in bending the C channel steel and the U bolts.
I had longer plate steel welded under the bottom C channel for strength- didn't solve the problem.
It was futile to straighten the C channel. A frame/alignment shop just didn't want to do it. They didn't want to give up insured car wreck time to fix my small problem.
I had 1/4" thick plates cut and welded inside the C channel under the U bolts to reinforce the upper and lower channels, turning them into "box" frames. Some of these plates had to go through the grinder to fit the bent curves of the C channel.
I chiseled out the wood to allow the inside leg of the U bolt get closer to the inside and center on the frame.
Next, some of the U bolts wouldn't stay centered during the torque. They would shift to the inside of the frame. Instead of having a straight across top of the U bolt, some had become angled downward to the inside. I had square 1" steel blocks welded to the upper outside C channel to keep the U bolt centered during the torque. This allowed the U bolts to extend 1" to the outside and inside, centering the bolts.
Last I had thick L angle steel cut to replace the flat U bolt cross plates. These didn't bend.
These were the steps to allow me to torque all U bolts to 75ftlbs:
remount body
convert C to box channel frame members
center the U bolts
use L angle U bolt cross plates
Before and after pictures to follow
