Aug-06-2014 01:42 PM
Aug-16-2014 07:25 AM
dougrainer wrote:Doug I assume by your answer that you don't get into the actual seal engineering or seal material. I don't know if you or Pete can talk to the engineers at HWH and find out the mechanics of what is causing so many seals to fail. When the seal is replaced is HWH replacing it with the same seal? Or does the new seal have more clearance or made from a different material or a new design ? If it is the same seal won't this problem occur again?Gjac wrote:dougrainer wrote:Doug you have described many times how these seals go bad and need to be replaced. What actually happens, do the seals swell causing a tight condition preventing full retraction? What are the seals made from that cause this condition? Is there a different seal material that you know of that can be used to prevent this swelling if that is what is causing this problem? This seems to be more of a problem with the newer HWH systems I don't see this amount of posts on the older joy stick models. Where different seals used, or more clearance between the shaft and seals?Mandalay Parr wrote:
Also may need to lube the cylinder shaft.
ANY lube is a band aid for the real problem. HWH jacks are immersed in ATF when retracted. Lubing will help for a few weeks and then the seals still cause the problem. Doug
The problem started about 10 years ago and took years to develope the problem(inner seals). Once HWH realized they had a problem with the seals(HWH DID back then recommended Lubing and such as they were not fully aware of the problem), they redesigned the seal material. BUT, for older than 5 year old jacks, the correct fix is either new cylinders or rebuild yours. It still happens occasionally under warranty or a few years out of warranty, but the repair and CORRECT fix is still the same---REPLACE or REBUILD the cylinder. You can continue to crawl under your RV every few months or so and hand wipe and use various lubricants to help free them up, but the problem remains. As I stated, about springs, yes the NEW style springs are tapered on the ends. If you have the old style springs it is best to replace all 8 of them with the newer stronger. BUT, NEW springs will NOT fix a sticking jack problem. They just retract quicker and are a tab bit stronger, but NOT strong enough to overcome sticking inner seals. The TEST for sticking inner seals is to extend the jacks for 24 hours THEN retract, If 1 or more do not fully retract within 5 minutes replace the cylinder. Just extending and THEN retracting, the inner seals will sometimes allow a full retract because you have just used them. Doug
Aug-16-2014 06:28 AM
kohlerguy wrote:
I was surfing around and found a hwh forum. Someone said the rear ones cost about $375 for the rebuild. Front ones are about $100.00 less.
Aug-16-2014 04:07 AM
Aug-12-2014 10:12 AM
Aug-11-2014 10:37 AM
Aug-11-2014 10:35 AM
Aug-10-2014 08:39 AM
Aug-09-2014 02:52 AM
Aug-08-2014 05:06 PM
Gjac wrote:dougrainer wrote:Doug you have described many times how these seals go bad and need to be replaced. What actually happens, do the seals swell causing a tight condition preventing full retraction? What are the seals made from that cause this condition? Is there a different seal material that you know of that can be used to prevent this swelling if that is what is causing this problem? This seems to be more of a problem with the newer HWH systems I don't see this amount of posts on the older joy stick models. Where different seals used, or more clearance between the shaft and seals?Mandalay Parr wrote:
Also may need to lube the cylinder shaft.
ANY lube is a band aid for the real problem. HWH jacks are immersed in ATF when retracted. Lubing will help for a few weeks and then the seals still cause the problem. Doug
Aug-08-2014 07:01 AM
dougrainer wrote:Doug you have described many times how these seals go bad and need to be replaced. What actually happens, do the seals swell causing a tight condition preventing full retraction? What are the seals made from that cause this condition? Is there a different seal material that you know of that can be used to prevent this swelling if that is what is causing this problem? This seems to be more of a problem with the newer HWH systems I don't see this amount of posts on the older joy stick models. Where different seals used, or more clearance between the shaft and seals?Mandalay Parr wrote:
Also may need to lube the cylinder shaft.
ANY lube is a band aid for the real problem. HWH jacks are immersed in ATF when retracted. Lubing will help for a few weeks and then the seals still cause the problem. Doug
Aug-06-2014 05:14 PM
Mandalay Parr wrote:
Also may need to lube the cylinder shaft.
Aug-06-2014 05:12 PM
Aug-06-2014 05:01 PM
Aug-06-2014 02:00 PM