What the Heck Was That Noise?!

steve R · 01-09-2009, 09:19 PM

I just bought a used '07 Sightseer, 35J. While getting ready for our second trip in the motorhome, I unplugged it from the shore power about 15 minutes later I walked in the motorhome and noticed that the check light on the refrigerator was blinking, so I turned it off to reset it, all of a sudden there was a loud bang. My wife, who was sitting on the bed said that the whole back of the motorhome shook. Upon investigation I could not find the source. I do not think that it was a propane leak because I turned the refrigerator off which would not create a spark to light the refrigerator. Camped in it for the next 5 days, with full-hook ups, and no issues. I had to turn the auxillary battery switch off while we were plugged in because on of my batteries were overheating. While getting ready to leave from our 5 day camping trip, we unplugged the motorhome, saying our goodbyes to our neighbors when we heard the loud bang again, it sounded as if it was coming from the rear of the coach. Once again, I do not believe it to be a propane leak because the auxillary battery switch was off, there fore there should have been no ignition source. I called the dealer where I bought the motorhome from and they said they did do a propane leak test and there was no evidence of any leaks. I talked to the poeple at Winnebago and they were clueless at what the noise could possibly be. Any help would be appreciated. Thanks.

steve R · 01-09-2009, 09:19 PM

I just bought a used '07 Sightseer, 35J. While getting ready for our second trip in the motorhome, I unplugged it from the shore power about 15 minutes later I walked in the motorhome and noticed that the check light on the refrigerator was blinking, so I turned it off to reset it, all of a sudden there was a loud bang. My wife, who was sitting on the bed said that the whole back of the motorhome shook. Upon investigation I could not find the source. I do not think that it was a propane leak because I turned the refrigerator off which would not create a spark to light the refrigerator. Camped in it for the next 5 days, with full-hook ups, and no issues. I had to turn the auxillary battery switch off while we were plugged in because on of my batteries were overheating. While getting ready to leave from our 5 day camping trip, we unplugged the motorhome, saying our goodbyes to our neighbors when we heard the loud bang again, it sounded as if it was coming from the rear of the coach. Once again, I do not believe it to be a propane leak because the auxillary battery switch was off, there fore there should have been no ignition source. I called the dealer where I bought the motorhome from and they said they did do a propane leak test and there was no evidence of any leaks. I talked to the poeple at Winnebago and they were clueless at what the noise could possibly be. Any help would be appreciated. Thanks.

NeilV · 01-10-2009, 01:26 AM

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by steve R:
I just bought a used '07 Sightseer, 35J. While getting ready for our second trip in the motorhome, I unplugged it from the shore power about 15 minutes later I walked in the motorhome and noticed that the check light on the refrigerator was blinking, so I turned it off to reset it, all of a sudden there was a loud bang. My wife, who was sitting on the bed said that the whole back of the motorhome shook. Upon investigation I could not find the source. I do not think that it was a propane leak because I turned the refrigerator off which would not create a spark to light the refrigerator. Camped in it for the next 5 days, with full-hook ups, and no issues. I had to turn the auxillary battery switch off while we were plugged in because on of my batteries were overheating. While getting ready to leave from our 5 day camping trip, we unplugged the motorhome, saying our goodbyes to our neighbors when we heard the loud bang again, it sounded as if it was coming from the rear of the coach. Once again, I do not believe it to be a propane leak because the auxillary battery switch was off, there fore there should have been no ignition source. I called the dealer where I bought the motorhome from and they said they did do a propane leak test and there was no evidence of any leaks. I talked to the poeple at Winnebago and they were clueless at what the noise could possibly be. Any help would be appreciated. Thanks. </div></BLOCKQUOTE>

If your refridgerator is malfunctioning it could be releasing propane. This could happen every time you unplug from shore power and it automatically switches over to propane.

Have you someone observe the sidewall vent on the refriderator the next time you unplug to see if there is any discharge from there.

You will also get a loud clunk from the transfer switch but that is more immediate and should happen the moment you unplug.

Belgique · 01-10-2009, 03:25 AM

Just grasping at straws here. My 08 35J Sightseer does not have a transfer switch...you plug in the shore power plug to a box in the utility compartment and it doesn't make a noise. Maybe you do have one.

I'd try turning off the propane at the tank and do things that you normally do to see if it happens again. If it does, it isn't propane...if it doesn't, then maybe it is? Keep us posted...like to hear the outcome of this. Steve

steve R · 01-10-2009, 05:34 AM

MY motorhome does not have a transfer switch. I did try to duplicate the proplem with the propane on while the motorhome is on the side of my house and I cant get it to do it again.

Rick Long · 01-10-2009, 07:48 AM

Steve... You do have a transfer switch but it's not something you have to do manually. I have an older RV and the transfer switch is a solenoid and can be heard when it's engaged. Yours is probably a small control relay on a printed circuit board and would make no noise.

Always turn off everything before un-plugging or plugging in, from shore power. The surges your creating by not doing so, could be catastrophic for some of your electronics and appliances.

Like some others have said.. It really sounds like a propane pop. If your frig is on auto when you disconnect, it will immediately switch to propane and try to light.

ps.. Replace BOTH of your house batteries at the same time. Be sure and test the batteries first... If by chance the batteries where in the middle of a desulphation or equalization cycle when you touched them, they could be quit warm.

Belgique · 01-10-2009, 10:06 AM

Rick...the 35J Sightseer does NOT have a transfer switch. I just happen to have the wiring diagrams and Wiring Install sheets on the desk in front of me.

What ours have is a box with a 30 amp receptacle in the utility bay. When you get under way, you plug your shore power cord into that receptacle if you want to use the generator. Our 2001 35U Itasca did have the transfer so I'm familiar with it.

autofish · 01-10-2009, 10:37 AM

Just a guess if it is not propane could it be hydogen from the hot gassing batteries.

steve R · 01-10-2009, 12:26 PM

One of the house is bad it does get very hot thats why I had the battery switch in the off position so the converter wasnt charging the batteries. With the battery switch in the off position their should no be power to anything that could spark a propane leak.

autofish · 01-10-2009, 12:50 PM

So Steve did the noise sound more like an exposion or a mechanical noise and where did it sound loudes Hope you solve the puzzle

Belgique · 01-10-2009, 01:19 PM

Another straw grasping here...are you sure that the battery disconnect switch stops the charger from charging the battery? I know it kills everything down stream from the battery but maybe not the charger? Even if it doesn't, I still can't guess what the pop is. There are no appliances aft of the fridge. Treat this a a rhetorical question...just thinking out loud.

Wait a minute: you weren't raising the jacks were you? They sometimes will make a bang.

Jeanne M. · 01-10-2009, 02:49 PM

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Wait a minute: you weren't raising the jacks were you? They sometimes will make a bang. </div></BLOCKQUOTE>

Exactly! I was just gonna say that! Sometimes our jacks 'bang' when they've just been raised or lowered. And if the jacks have been extended a long time they'll 'bang' quite loudly!

steve R · 01-10-2009, 03:29 PM

It's hard to tell if the noise is more mechanical or explosion if I had to guess I'd say mechanical. When I called Winnebago they told me that turning the battery switch off would not charge the batteries but as long as your pluged in everything else will work. I was not raising the jackes. Thanks everybody for your help.

Eric Hennen · 01-11-2009, 07:18 AM

Here's another possibility: When we put our middle slide in too hard, pushing the button until the pump dogs down, the slide mechanism will bang some time afterward. It's loud. If you have a back bedroom slide, try not putting it in so hard.

steve R · 01-11-2009, 10:52 AM

I think Eric Hennen is on to something. My slides are electric and not operated by a pump. The first time it happened my wife was sitting on the bed and said the whole bed shook. But whats causing the noise? Eric are your slides pump drive or electric motor.

Belgique · 01-12-2009, 03:17 AM

My J's slides are electric, like yours, but I've never heard anything like this. The manual tells you to pull them in until they stop. But hey, we're all running out of ideas so this bears checking into. The 35U had the HWH hydraulic and they would make noise sometimes.

I thought I had it nailed on the jacks...dang. A great mystery.

Sammie · 01-12-2009, 04:32 PM

Just a wild guess. Were you using the propane heater at the time? My friend had a problem with his heater where the propane gas would come on when he turned his heater on but the ignitor would not light the gas for a few seconds. When it finally did light there would be a LOUD BANG that sounded like an engine backfire.