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Background
The potential for the lift pump bracket on my Jayhawk 26Y pump to fracture and in turn, allow the pump to fall off, caused me to investigate and improve its mounting.
Although the manufacturer has not recalled my model for this problem my gusseted bracket looks just like the one that did fracture.
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| Evidence of other owners failed lift pump bracket |
The problem is that this heavy pump is mounted to a cantilevered bracket that is welded to the chassis frame. Although the bracket is stout it has a failure point just above the gusset at the frame. Note that the gusset is not connected to the frame. This cantilever allows the bracket to vibrate.
I found I could move the bracket and pump 1/8" at its longest point by pushing/pulling with my hand. I feared that the rough vibration that a RV experiences during travel would cause the bracket to sheer off at its weak point.
Since Jayco notified me that my RV is not on the list to fix this problem I set out to reduce the possibility of pump bracket failure or at least ensure the pump would not fall out the bottom of the RV in the event it did fail.
The Recalls Approach
My Stock Bracket
Notice that my bracket hangs below the frame but the top of the gusset is not welded to the frame leaving the pup hanging on a cantilever whose stress point is exactly where the bracket fails.
The Approach
After spending time under the RV and creating multiple CAD models of approaches to fixing this problem I was inspired by this approach that uses UniStrut as a support beam. This beam is anchored to both sides of the chassis frame:
A Unistrut beam is placed perpendicular to and clamped on the RV's C-channel frames. This beam better supports the pump and eliminates the cantilever. Clamping avoids drilling any holes in the frame.
Unfortunately, in the case of my model RV (Jayhawk 26Y), the placement of the pump is in line with the muffler and drive shaft so a beam cannot be easily placed on the lower lip of the frame, under the pump, and from the frame rail to rail without significant relocation of the entire pump assembly.
I elected to put the beam on top of the frame rails and drop a rod to the underside of the pump bracket to stabilize it. The modification, therefore, mounts to the frame and the existing pump bracket.
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Beam clamped at the passenger side
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3/8 all-thread hanger rod attached to pump bracket from above
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Detail of extension attached to the underside of pump bracket.
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Top view of crossbeam attachment
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Fabrication
The bulk of the modification used Unistrut parts. No welding was necessary and there were no holes drilled in the RV.
I fabricated two C channel saddle brackets to ensure that the hanger stayed centered everything else was made from off-the-shelf parts.
Fabrication consisted of:
- Cutting the crossbeam, pump extension bracket, and all-thread hanger.
- Fabricating the hanger saddle brackets.
- All bolts were locked with either jam nuts or self-locking nuts
- The assy was painted to prevent corrosion and make it "pretty".
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| The proto assembly |
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| Crossbeam length |
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Pump bracket extension dimension
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3/8 all-thread length
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| All-thread centering saddle bracket 2"x 2" w 3/8 hole in the center |
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Unistrut clamps on each end of the crossbeam
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All parts after painting
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Fender washer placement in the pump extension bracket. A 9/16 deep socket was used to install the nuts.
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Installation
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Lay and loosely clamp the crossbeam on the passenger side frame .....
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... to the driver's side and attach the beam clamps at each end
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The driver side (under the crossbeam and above the pump)
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The driver's side attachment will require cutting the wire bundle tie wrap. Then the wire loom is pulled aside so the clamp bolts are visible. About 3/4" was cut off the clamps u-bolt just to ensure that they would not chafe the wiring. The wire bundle was repositioned and re-tie wrapped as a final step in the installation.
The crossbeam should be locked down centered over the pump's mounting bracket on the driver's side and tight up against the muffler bracket on the passenger side. This will position the crossbeam at a slight angle, the passenger side will be forward of the driver side. This slight angle does not create a problem.
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The Hanger Assy
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Hanger extension bracket placement (before painting and washers)
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The hanger rod is assembled between the pump bracket extension and the cross beam.
Attach the pump bracket extension to the pump bracket loosely, using existing hardware. A large fender washer is added and then the lock washer and nut are installed. The photo above does not show the washers as I added them later. However, the photo below shows the fender washer placement.
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Washer Placement
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Four 3/8 nuts are threaded a few inches from either end of the hanger rod and then the rod is inserted between the crossbeam and the pump extension bracket. The 4 nuts, two upper and two lower will be used to adjust and lock-in the gap between the pump extension brack and the crossbeam.
The upper saddle bracket is placed under the crossbeam but on top of the 2 upper adjustment nuts
A locking nut and fender washer are assembled on top of the crossbeam.
The hanger rod is connected to the pump's extension bracket with the saddle bracket under the extension bracket and a washer and the two nuts above the bracket.
After initial installation, the hanger rod should be free to move up/down a 1/4" or more, ready for adjustment.
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Lower Hanger Attachment
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Upper Hanger Attaachment
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Upper Hanger Attachment Adjusting and Locking Nuts
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Adjustment
The hanger rod is not intended to put tension on the pump bracket rather just stabilize it. The adjustment nuts on the hanger allow a fixed dimension to be set between the crossbeam and the pump's mounting bracket keeping the pump's cantilever mount from vibrating under load but not applying any tension.
Before you adjust and tighten the hanger rod you can grab the pump's extension bracket at its extreme, push up and pull down, and feel its movement. Mine was about 1/8". The adjustment is intended to eliminate this motion.
The upper and lower hanger rod bolts are adjusted so that there is NO tension on the pump bracket but the movement of the pump mount is restricted. You don't want the rod pulling up on the bracket or inversely pushing down on it.
To adjust:
- Loosen the 2 upper and 2 lower adjustment nuts so the rod is free to move up/down.
- Then tighten the locking nut below the pump extension bracket so that its threads are fully engaged and the thread is flush with the nut. You will have to hold on to the rod with a vice grip and loosen the lower adjusting/locking nuts.
- Then adjust the nut that is atop the cross beam until it is snug against the cross beam. At this point, the rod is snuggly between the cross beam and pump extension bracket but not putting ANY tension on the pump's mounting.
- You should be able to tap the rod left-right to get it as vertical as possible.
- Tighten the upper adjustment nut upward against the centering bracket
- Tighten the lowermost adjustment nut downward against the pump extension bracket.
- The rod should now be firmly attached to the cross beam and the pump extension bracket without any tension on the pump mounting.
- To verify grab the pump extension bracket at its extreme and push up/pull-down. There should be no motion. If there is, tighten the rod adjustment nuts as appropriate to eliminate the motion but not create any tension.
- When the adjustment is complete tighten the rod's upper and lower locking nuts against their respective adjustment nut.
Hints
- Use locking or jam nuts everywhere.
- Mount the extension bracket using large fender washers followed by lock washers and then the nuts. [re-use the hardware that previously mounted the pump]
- The application of a removable thread locker is a good idea.
- Re-tie the cables with tie wraps. In my case, I took the opportunity to tie up loose wire and plumbing.
- DO NOT OVERTIGHTEN the hanger rod.
- While your down there spray some corrosion inhibitor on rusting parts
Parts
- Cross Beam 1 5/8 x 42" Unistrut
- 2x beam clamps
- Hanger Rod: 3ft 3/8-16 all-thread cut to 14 1/2"
- Hanger rod Hardware [in order of assembly top-bottom]:
- Upper locking nut: 3/8-16
- Fender washer with drilled 3/8 hole
- Saddle bracket: fabricated from 2 inch C channel
- Upper adjustment nut: 3/8-16
- Upper adjustment locking nut: 3/8-16
- Lower adjustment locking nut: 3/8-16
- Lower adjustment nut: 3/8-16
- Fender washer with drilled 3/8 hole
- Saddle bracket: fabricated from 2 inch C channel
- Lower locking nut
- Pump Extension Bracket: 1 5/8 x 12 1/4"
- Pump Extension Bracket Hardware:
- 2 x fender washers with drilled 3/8 hole
- 2x lock washers (original reused)
- 2x 3/8 nuts (original reused)
All the parts except the saddle brackets came from big box stores.
The centering brackets may be overkill. Alternately use fender washers. I already had some 2" channel in the shop. Something like this is equivalent
https://www.mcmaster.com/7779T39/No holes or welding on the RV.
Conclusion
I plan to leave this fix installed until it is decided that the recall applies to my RV. If my RV is added to the list I will consider having the recall installed instead of this solution.
As a stopgap to the new recall bracket, this approach affords at the least a temporary DIY solution that:
- Can be shop made with normal hand tools
- Parts can be sourced at local home stores
- Does not require any welding or drilling in/on the RV
- The pump does not need to be relocated. I don't think the hydraulic hoses in my RV are long enough to move the pump.
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Enjoy and comment,
Don
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