Reply
 
Thread Tools Display Modes
Old 07-27-2016, 04:20 PM   #21
Senior Member
 
I-RV's Avatar
 
Join Date: Jun 2013
Location: Mount Laurel, NJ
Posts: 1,006
Quote:
Originally Posted by accumack View Post
I had it until I did the Marvel Mystery oil (I have 3 of the new plates). It was the jacks creaking / settling it went away after a few cycles after adding the MM oil to the reservoir.
That would be Marvelous if Marvel Mystery oil is the solution. Not debating that it isn't the solution, but need more corroboration. Why do you have three new plates?
Hank
__________________

__________________
Gale & Hank- 2012 Berkshire 390BH
I-RV is offline   Reply With Quote
Old 07-28-2016, 08:00 AM   #22
Junior Member
 
Join Date: May 2016
Location: Poulsbo, Wa
Posts: 22
How much MM oil do you add? When do you check your fluid level for the Jacks? All up, slides in? Or all down and out?
__________________

__________________
55post is offline   Reply With Quote
Old 07-28-2016, 08:05 AM   #23
Member
 
Join Date: Jul 2015
Posts: 91
Jacks up and slides in.
__________________
Bunci is offline   Reply With Quote
Old 07-28-2016, 09:59 AM   #24
Senior Member
 
Join Date: Apr 2012
Location: West Michigan/Fort Myers
Posts: 3,927
The service person added a qt to my system.
__________________
Phil57 is offline   Reply With Quote
Old 07-28-2016, 11:40 AM   #25
Senior Member
 
I-RV's Avatar
 
Join Date: Jun 2013
Location: Mount Laurel, NJ
Posts: 1,006
Has everyone that added Marvel Mystery oil had the clinks/chirps sounds go away from the jacks?
Hank
__________________
Gale & Hank- 2012 Berkshire 390BH
I-RV is offline   Reply With Quote
Old 07-28-2016, 11:57 AM   #26
Senior Member
 
Join Date: Apr 2012
Location: West Michigan/Fort Myers
Posts: 3,927
Not me.
__________________
Phil57 is offline   Reply With Quote
Old 07-28-2016, 07:02 PM   #27
Senior Member
 
Mmnsc's Avatar
 
Join Date: Sep 2012
Location: Charleston County SC
Posts: 503
Still there even after adding 1 qt Marvelous Mystery Oil


Sent from my iPhone using Forest River Forums
__________________
Mmnsc is online now   Reply With Quote
Old 07-29-2016, 07:48 AM   #28
Senior Member
 
I-RV's Avatar
 
Join Date: Jun 2013
Location: Mount Laurel, NJ
Posts: 1,006
Okay, we have two that still have clinks after adding Marvel Mystery Oil.

My next question is to those that have had their jack pads replaced with heavier duty ones. Do you still have clinking sounds?
Hank
__________________
Gale & Hank- 2012 Berkshire 390BH
I-RV is offline   Reply With Quote
Old 07-29-2016, 07:53 AM   #29
Senior Member
 
CAT-RN's Avatar
 
Join Date: Jul 2014
Posts: 5,526
Clunking noise after axle/tire upgrade

Quote:
Originally Posted by I-RV View Post
Okay, we have two that still have clinks after adding Marvel Mystery Oil.



My next question is to those that have had their jack pads replaced with heavier duty ones. Do you still have clinking sounds?

Hank

I not sure how it could be jack pads? If there would be some deflection there it would be just a one time clink?

I believe on mine it's the jack leaking back. (Very little). Or the jack pads settling into the surface their on.

And I haven't replace my pads so I know I didn't respond to your question.

Russell
__________________
CAT-RN is online now   Reply With Quote
Old 07-29-2016, 01:31 PM   #30
Senior Member
 
I-RV's Avatar
 
Join Date: Jun 2013
Location: Mount Laurel, NJ
Posts: 1,006
Quote:
Originally Posted by CAT-RN View Post
I not sure how it could be jack pads? If there would be some deflection there it would be just a one time clink?

I believe on mine it's the jack leaking back. (Very little). Or the jack pads settling into the surface their on.

And I haven't replace my pads so I know I didn't respond to your question.

Russell
Hi Russell - I never implied that the jack pads deflect. My contention is that the noise comes from the contact area where the round end rim of the hydraulic ram rests on a race-track like ring of the jack pad. At this point contact mating of the two parts, there can be a variable amount of psi (pounds per square inch) which can vary because of the weight from the RV and the angle of the jack pad (when it is tilted).

I'd just like to explain psi with an analogy. Say there is a 150 lb women wearing spiked heels. When she steps on the front of the shoe with a 2 x2 area (4 sq. in), the shoe is putting 37.5 psi on the floor. When she puts all her weight on a 3/8 x 3/8 heel (0.14 sq in), she is placing 150 lb on 0.14 sq in, which comes to 1,071 psi on the floor. No wonder that the heel leaves marks in some floors.

Now back to the motorhome. Say one of the rear jacks is supporting 9,000 lbs. That means (approximately) say the 8 x8 jack pad has 9000 /8x8, or 140 psi between the pad and ground. Even so, if the ground is not firm the pad sinks in. However at the Achilles heel, the contact area of the mating contact of the ram's rim to the pad, there might be 2 sq inches of contact. This means that there is 9000/2 or 4500 psi on the contact. However, if the pad is very tilted with say 1/4 sq inch of contact, there will be 9000/0.25 or 36,000psi.

Punch trough of the ram punching through the pad has happened to our fellow forum members. Just using common logic, I believe that the punch-through occurs after a long duration of metal fatigue weakening at the contact points of the ram to the pad. Does this weakening emit sound. Well I am not a metallurgist, but a PhD metallurgist says yes for some types. See the two links below and especially the second one.......

Fatigue (Failure Mechanism) | Metallurgical Associates

https://www.reddit.com/r/askscience/...n_they_strain/

If the noise is from fretting, that is just the two surface grinding in together in knocking down the Asperities. If the noise is from brittle fracturing, I can see this leading to punch through.

On a side note, when I put boards under my old style pads, with the pads being parallel with the moho (non-tilted), I get the bolt head impression of the bolt holding the pad to the ram on the wood pad. Further more, I have no clinks because the bolt head is releaving a lot of pressure off of the the pad. Does that tell you something.

Russell; sorry I unloaded on you, but I just want to get to the bottom of thins clinking thing. I shared my beliefs and hope others chime in.
Hank
__________________

__________________
Gale & Hank- 2012 Berkshire 390BH
I-RV is offline   Reply With Quote
Reply

Tags
axle, noise, tire, upgrade

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off




» Virginia Campgrounds

Reviews provided by




ForestRiverForums.com is not in any way associated with Forest River, Inc. or its associated RV manufacturing divisions.

Our Communities

Our communities encompass many different hobbies and interests, but each one is built on friendly, intelligent membership.

» More about our Communities

Automotive Communities

Our Automotive communities encompass many different makes and models. From U.S. domestics to European Saloons.

» More about our Automotive Communities

Marine Communities

Our Marine websites focus on Cruising and Sailing Vessels, including forums and the largest cruising Wiki project on the web today.

» More about our Marine Communities


Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -5. The time now is 02:11 PM.