Frame Popping while on Jacks

[mike45b]

Our 2016 Cornerstone 45B makes load popping noises while we are parked and leveled on the jacks. It comes from the front and the back and seems to come from the frame. Sometimes it happens when we are moving around inside, but it will also do it with no one inside. Our neighbor in the RV park we are in has a 2016 Aspire that is popping also. Has anyone else had this problem and is there a fix?

[Kiawah]

I suspect the hydraulic fluid in the jacks is slipping past the closed solenoid. As the pressure in the cylinder leaks down, coach drops slightly.

At the jacks, measure the distance between the frame and the pad, and see if it's dropping over time. If so, you'll know which jack(s) and will probably need to replace a valve, which in Tiffins HWH's are easy quick fixes.

[brobox]

Here are several Entegra posts and remedies. https://www.google.com/search?q=Ente...earch=irv2.com

[Flanz]

Actually, it’s probably a change in ambient temperature that is causing this issue. This is a know issue with other manufacturers out there. Make note of the day temperatures and as the temperature drops you’ll probably here the popping noise. It seems to only happen during a big change in temperature. Should happen at night them as the temps stabilize popping may stop only to start again as the day temps warm...

I’ve read several posts over the years on this and it could be the expansion and contraction of the transmission fluid in the hydraulic system. Some say to put a quart of Marvel Mystery Oil and others use Caterpillar hydraulic additive 1U9891. there are other fluids, but from what I’ve read the CAT fluid appears to work the best.

Have a look at the attached file and do some searches....

[backwater4]

Had the same thing a while back. I was told to run jacks all the down ,raising coach off the ground. Let it sit for 20 minutes, retract jacks all the way up, then relevel. No more popping for a couple years now.

[Kuppajoe]

I added the Caterpillar hydraulic additive 1U9891 about a year ago but it did not slow down the popping. Hopefully the information in one or more of the above posts will shed some light on the situation. During our annual maintenance this past September at Spartan, they did a hydraulic fluid change but the amount of popping seems to be about the same.

[Fiesta48]

Easy fix. Put wood blocks under the jack pads.

[Hivoltmaint.]

See post #2. In my 5th wheel we had the same popping noise. I removed almost a quart of hydro fluid and added the motorcycle fork fluid. Problem solved.

[RogerBall]

Our Anthem has popped while on jacks since day one. I added one quart of the CAT magic fluid with minimal results. Still popped all night and day.

Then I found the system purge procedure on the Equalizer troubleshooting website that Backwater4 refers to above.

It worked great! Here's the procedure from Equalizer:

"Hydraulic System Purge Process
After the installation of the hydraulic jack system, the system must be
purged of air, which is replaced with hydraulic fluid. Occasionally,
this process is not done adequately and some air will remain in the
system. This causes the jacks not to run as efficiently as they should,
and may result in the jack legs sagging out of their stowed (retracted)
position. This procedure will solve the problem.
· Make sure the pump reservoir is filled with hydraulic fluid.
There is a fill line on the reservoir.
· Using either the manual buttons or the All Retract button on the
Control Panel, fully retract all of the jacks.
· Re-check the fluid level – add as necessary.
· Using the manual buttons on the Control Panel, fully extend all
jacks to their maximum extension. This will require alternating
between the front two jacks and the rear two jacks – the crossframe
twist limiter in the Control Panel will not allow you to fully
extend one jack at a time. Keep the jacks extended for at least
15 minutes.
· Again, fully retract the jacks. Re-check the fluid level – add as
necessary.
The process is complete."

It's a little unnerving to see how high the jacks will lift either end. Be sure to wait at least 15 minutes between lifts to allow the pump to cool. We did just one lift for each end and that seems to have been enough.

Hope it works for you!

[Fattman-Litlboy]

Thanks for the advice. We had this problem last July in Breckenridge, CO, and recently in Jacksonville, FL. We'll give this a shot. Happy New Year!

[Tall Tex]

I had the same popping and put it on my list for AIR at Middlebury. They put in an additive (didn’t say what) but the popping is now completely gone.

[brobox]

Originally Posted by Tall Tex

I had the same popping and put it on my list for AIR at Middlebury. They put in an additive (didn’t say what) but the popping is now completely gone.

When I was there they were using Marvel Mystery Oil. On mine they also did the raising the coach, but instead of letting it sit like they do now, they did a couple of full cycles to bleed the air and burnt up the motor. I guess now they have changed that to "let it sit fully extended for 15- 20 minutes". I believe the air bleed is the most important part.

For those that are going to DIY, remember to drain a quart of fluid off before adding the new fluid. I know one forum member that did not and had a mess to clean up.

[mike45b]

Hi to all, I just would like everyone to know I and we tried all the great info the mmo change out and then raising it up all the way up on jacks and let it sit for 20 min and level it again The coach did not make a popping for almost 24hr on all them then they all began popping again in front and then the back around jack area vice-versa about every 45 min to 2hrs nonstop there are 2 other coaches here in the park we are all together and we all have tried this and all are still doing it but they seem not as bad but still popping dose anyone have more ideas or solutions to this or try redo the steps please help driving me up the wall thanks mike looking forward to answers

[Lault]

As I said Im waiting for the magic fix??