Foretravel Owners' Forum

Foretravel Motorhome Forums => Foretravel Tech Talk => Topic started by: Tom Endres on November 13, 2019, 01:03:42 pm

Title: Vacuum generator for slide bladder
Post by: Tom Endres on November 13, 2019, 01:03:42 pm
Does anyone have the part number for the front slide on a 2002 U295.
The last time I extended the slide it sounded as though the slide  was contacting the bladder. I had plenty of air pressure.
Thanks in advance.
Title: Re: Vacuum generator for slide bladder
Post by: Rich Bowman on November 13, 2019, 03:14:46 pm
It is a venturi vacuum generator built into the slide manifold block.  Mine is located high on the right side wall in the driver side storage bay.  No moving parts on the vacuum generator but there are 2 solenoid valves.  One is the same as on a 6-pack and one is different.  Not sure which one controls the vacuum generator actuation.  I would try to contact HWH.  Can you see the bladder retract when you turn the key?

Rich
Title: Re: Vacuum generator for slide bladder
Post by: Roger & Susan in Home2 on November 13, 2019, 10:09:07 pm
You should not hear any squealing when you extend or retract the slide.  When you turn the key in your coach to get ready to extend or retract compressed air makes a low pressure which deflates the bladder as Rich explained.  The yellow light comes on in the 2002 (maybe not all) and later coaches when the vacuum reaches a preset low pressure.  You should be able to see light between the slide and the retracted bladder. Check before you move the slide.
Title: Re: Vacuum generator for slide bladder
Post by: Woody & Sitka on November 13, 2019, 10:26:45 pm
The original manifold in my 2001 is part# AP20078.  I have it in my hands as it was removed last week after the slide bladder was replaced at MOT.  New bladder design needs a higher capacity manifold evidently but this one was working fine.  I kept it for a spare or a door stop.  Woody.
Title: Re: Vacuum generator for slide bladder
Post by: rbark on November 14, 2019, 01:57:40 am
I kept my old manifold also, if anybody needs it.
Title: Re: Vacuum generator for slide bladder
Post by: Roger & Susan in Home2 on November 14, 2019, 08:27:21 am
In the air line from the bladder manifold to the bladder add a quarter turn valve and a pressure gauge.  This lets you monitor the pressure in the bladder. If you suspect a leak, closing the valve with the bladder inflated will isolate the bladder.  If the pressure drops then something (likely the bladder) after the valve is leaking. If it does not then something before the valve (likely the manifold) is leaking.

If you think the bladder is dragging on the slide when the slide is moving try spraying the area with soapy water to reduce friction and minimize the possibility of damage to the bladder. This is a temporary fix, find out why the bladder is not fully retracted.
Title: Re: Vacuum generator for slide bladder
Post by: folivier on November 14, 2019, 09:48:49 am
Would it be possible to add a vacuum pump to each bladder manifold?
I'm not familiar with the Foretravel system but know a few Newell guys that have added an electric vacuum pump to theirs and it works nicely.  I can get the link to that info if anybody is interested.
Title: Re: Vacuum generator for slide bladder
Post by: DavidS on November 14, 2019, 09:51:08 am
Would it be possible to add a vacuum pump to each bladder manifold?
I'm not familiar with the Foretravel system but know a few Newell guys that have added an electric vacuum pump to theirs and it works nicely.  I can get the link to that info if anybody is interested.
I dont think it would hurt... I have both my old ones and maybe they can be modified?
Title: Re: Vacuum generator for slide bladder
Post by: folivier on November 14, 2019, 10:22:13 am
Anybody should be able to see this post as a guest.  The poster is the same Tom who sells the HWH leveling kits. 
hwh slide seal vacuum pump installation (http://newellgurus.com/showthread.php?tid=3478)
Title: Re: Vacuum generator for slide bladder
Post by: Rich Bowman on November 14, 2019, 06:32:36 pm
I think that not all 2002 coaches have a sensor to turn the light on steady when the bladder is deflated.  Ours is an early 2002 (built Aug 2001) and appears to still just use a timer to activate the light.  We have to visually check for deflation.  It usually takes about 5-10 seconds after the light goes on steady.

I'd suggest that everyone check visually a few times to make sure they can trust their light to give a reliable indication of bladder deflation.

Rich
Title: Re: Vacuum generator for slide bladder
Post by: Roger & Susan in Home2 on November 14, 2019, 06:42:46 pm
We look every time to make sure the bladder is deflated before moving the slide. 
Title: Re: Vacuum generator for slide bladder
Post by: Tom Endres on November 15, 2019, 10:52:03 am
Thanks all, for the replies.
The parts listed are obsolete. Think I'll attempt a rebuild of the unit.
Title: Re: Vacuum generator for slide bladder
Post by: Roger & Susan in Home2 on November 15, 2019, 12:38:27 pm
We had our bladder manifold replaced at HWH with a rebuilt one.  About $250 vs 3-4x.  Same warranty.  It has worked fine for the last 6 years.  I think it is usually the solenoid valve that starts to leak.
Title: Re: Vacuum generator for slide bladder
Post by: Travelin' Man (RIP) on November 15, 2019, 12:44:45 pm
Is a DIY rebuild possible?
Title: Re: Vacuum generator for slide bladder
Post by: Roger & Susan in Home2 on November 15, 2019, 12:57:16 pm
I would think so although the 2003 version might be different from the 2001. 
Title: Re: Vacuum generator for slide bladder
Post by: Travelin' Man (RIP) on November 15, 2019, 01:32:18 pm
Wonder if anyone has been in there to see what parts, etc. are needed and if they are available?
Title: Re: Vacuum generator for slide bladder
Post by: Rich Bowman on November 15, 2019, 02:25:42 pm
It's been a couple of years since I worked on mine.  I think there are only two parts to rebuild, the solenoid valves.  See my earlier post.  The rest is basically the manifold block.  I'm sure any needed parts are available from HWH.

Rich
Title: Re: Vacuum generator for slide bladder
Post by: Tom Endres on November 16, 2019, 11:23:22 am
I certainly appreciate everyone's
I'll pull the unit and check it out.
Thanks.