Foretravel Owners' Forum

Foretravel Motorhome Forums => Foretravel Tech Talk => Topic started by: Peter & Beth on March 16, 2012, 09:27:35 pm

Title: Power Tech 8KW Vibration Isolators
Post by: Peter & Beth on March 16, 2012, 09:27:35 pm
Ever since the fuel lines were replaced by Cummins, when starting or shutting down the generator, there's a rattling going on that's disturbing.  One job I'll tackle next week is to examine what's going on in the genny compartment.  It could be that the fuel lines need to be properly secured.  Or, it could be spent isolators allowing too much vibration amplitude.

Has anyone replaced the vibration isolators in one of these units?  What level skill is this job?  And, besides Power Tech, where did you get the isolators?  Does any one know the isolator specifications for these units?

Peter
Title: Re: Power Tech 8KW Vibration Isolators
Post by: Barry Beam on March 17, 2012, 12:22:03 am
Ever since the fuel lines were replaced by Cummins, when starting or shutting down the generator, there's a rattling going on that's disturbing.  One job I'll tackle next week is to examine what's going on in the genny compartment.  It could be that the fuel lines need to be properly secured.  Or, it could be spent isolators allowing too much vibration amplitude.

Has anyone replaced the vibration isolators in one of these units?  What level skill is this job?  And, besides Power Tech, where did you get the isolators?  Does any one know the isolator specifications for these units?

Peter
Check this thread
Powertech 10KW rubber mount (http://www.foreforums.com/index.php?topic=10616.msg50492#msg50492)
Title: Re: Power Tech 8KW Vibration Isolators
Post by: Bill Willett on March 17, 2012, 12:46:43 am
Peter,check the bolt's that lock the slide tray.
Title: Re: Power Tech 8KW Vibration Isolators
Post by: Pierce & Gaylie Stewart on March 17, 2012, 01:58:35 am
Barry has a good link. There are two different styles of isolators available. Price about the same.

Have the generator door open when you shut it down and watch the exhaust system. My exhaust pipe was banging on the back wall of the compartment when I shut down. Was also rubbing and causing some vibration plus wore through the wrap on the pipe.

Bill also has a good point about the bolts.

Pierce
Title: Re: Power Tech 8KW Vibration Isolators
Post by: Barry & Cindy on March 17, 2012, 08:42:25 am
Generator vibration when starting and mostly stopping is caused by the two slide 'lock' bolts not being tight enough. Take your 1/2" wrench and crank it
Title: Re: Power Tech 8KW Vibration Isolators
Post by: Peter & Beth on March 17, 2012, 08:47:11 am
As usual, all excellent posts.  Many thanks to all.

Peter
Title: Re: Power Tech 8KW Vibration Isolators
Post by: Felix and Gail on March 18, 2012, 02:43:40 am
When I removed the bottom steel plate under the generator to change the belt I found two V type bracket tack welded to the frame that the back of the generator slide fits into when the generator is pushed into place. Both of the welds had failed and the angle brackets were just sitting in the tray. I bolted the brackets back into place and lined them with gasket material that were cut to fit and glued. This stopped the rattling and decreased the vibration. Thes brackets can be seen by looking between the generator and pan on either side.They can be seen much better if the generator is pulled out a few inches. It appears these brackets secure the back of the generator pan to a frame crossmember when the two front bolts are tightened. 
Title: Re: Power Tech 8KW Vibration Isolators
Post by: Peter & Beth on March 18, 2012, 09:50:28 am
Felix,
Thanks for the details of the compartment layout.  The more knowledge I have about how things are laid out, the better chance that I can locate the problem.
Peter
Title: Re: Power Tech 8KW Vibration Isolators
Post by: Kent Speers on March 19, 2012, 10:14:50 am
Peter, we just recently had a very irritating generator vibration fixed at FOT by Wayne. I had previously had the generator looked at by both MOT and an OKC RV dealer to no avail.  Within a few minutes Wayne at FOTfound that the generator housing was touching the left hand rail of the generator slide and that the rubber vibration grommets between the muffler and the frame had been removed. I also found the same situation on another 93 U300 while at Camp Foretravel. However, based on you description, I'm betting on the slide frame.

Wayne also said in all of his years at Foretravel. He had never seen the Powertech Vibration dampers worn out. He had replaced a few at customers requests or because they had been damaged but never found the old ones worn by age or use. FWIW
Title: Re: Power Tech 8KW Vibration Isolators
Post by: J. D. Stevens on March 19, 2012, 10:51:51 am
Peter, we just recently had a very irritating generator vibration fixed at FOT by Wayne. I had previously had the generator looked at by both MOT and an OKC RV dealer to no avail.  Within a few minutes Wayne at FOTfound that the generator housing was touching the left hand rail of the generator slide and that the rubber vibration grommets between the muffler and the frame had been removed.

Wayne is "Da Man!" He has done work on our coach a couple of times. He has diagnosed and fixed several items to my satisfaction. He has fixed steering alignment, air leaks, wheel seals, generator preheat/startup, furnace, water heater, and steering gear. I just scheduled an appointment at FOT for a repair that could have been locally. I chose FOT because I have been pleased with the work they have done for me in the past.

The information about vibration and isolators will likely help some folk address vibration issues on their generators.
Title: Re: Power Tech 8KW Vibration Isolators
Post by: Peter & Beth on March 23, 2012, 04:09:37 pm
Thanks to all who contributed to this post.  As usual you folks are "right-on-the-mark".  I tightened the generator slide tray "holding" bolts, and voila the rattle is history.

Again, Thanks!

I'm Happy Camper Again!        :dance: