|
|
11-05-2007, 01:42 PM
|
#1
|
Senior Member
Join Date: Oct 2007
Location: Huntington WV
Posts: 1,041
|
Air Pressure Multiplier
This little , 10 x 4 x 4 inches, device takes air from your coach supply and doubles the pressure. It has been mentioned on the forum before. It is a convenient way of providing the higher pressure needed to inflate your front tires to 120 psig. Hard to get there with just 120 psi max from your engine compressor
Newell sells them for $258.
How does it work? Great !!!!, No, seriously, the concept is simple. Pressure is measured in lbs per square inch, so if we had 50 psi pressing on a disc that was 3 square inches in area then that would equal 150 lbs force. If we coupled that disc to one that was only 1.5 square inches in area then it would exert 300 pounds force. That's how the multiplier works. The incoming air presses on a piston which is coupled to another piston of half it's area. When the pump reaches the end of it's stroke, the air is released on the incoming side, and a spring returns it for the next stroke. It builds pressure on the outbound side with each stroke. So if the incoming pressure is 100, the pump is capable of producing 200 psi. Of course the pump does not produce a large volume of air, but you don't need it for topping off the tires. It does have a regulator so you can control the maximum pressure out of the multiplier.
At $258 I could have certainly bought a nice pancake compressor capable of running at 150 psi. I already had a compressor for the garage, plus you need to actually have the compressor on the bus
So I went for the more expensive but elegant solution. With the engine compressor, aux compressor, and the 12 volt compressor already on the bus, I didn't think adding a fourth was the right thing to do.
Before the multiplier, it would take about ten minutes of fiddling to get the front tires up to about 115. That included bleeding the system air down and only inflating when the sytem pressure was at it's max. With the multiplier, it took all of two minutes to top off the tires. Sweet !!!
__________________
__________________
Richard Rhonda Ty and Alex Entrekin
1995 Newell # 390 DD Series 60, Allison World Trans
Subaru Outback toad
CoMotion Tandem
Often wrong, but seldom in doubt
Rhonda's chronicle https://wersquared.wordpress.com/
|
|
|
11-05-2007, 03:08 PM
|
#2
|
Senior Member
Join Date: Feb 2006
Location: Texas
Posts: 1,558
|
Wholeheartedly agree!! I run 120 psi in my front tires and it took forever without the multiplier since the engine mounted air compressor cuts off about 125 and has to be bled down to about 110 to cycle back on.
__________________
|
|
|
11-05-2007, 10:07 PM
|
#3
|
Senior Member
Join Date: Mar 2007
Location: mesa, az
Posts: 1,375
|
i bought it as well and it works as well as we are all saying. right now i have it loose and am deciding if i want to mount it or not.
tom
|
|
|
07-22-2009, 12:25 PM
|
#5
|
Senior Member
Join Date: Oct 2007
Posts: 279
|
Forest, purchased the multiplier from Newell for our coach. It is excellent to plug into the air chuck on the passenger side of my engine compartment and fill the tires as needed before any trip. I think I purchased the air hose and accessories for checking air pressure etc. at home depot or lowe's. I have the old fashioned readout on the tire gauge but I have seen Wally's and his is digital. Probably much more accurate.
David
|
|
|
07-22-2009, 12:36 PM
|
#6
|
Senior Member
Join Date: Sep 2008
Location: Thibodaux, LA
Posts: 1,221
|
I tried calling Newell yesterday but Chuck (parts guy) is off all week. The girl who answered didn't quite know what I was talking about, said they would have to install fittings, etc. and would be about $400. If the only fittings needed are quick connects, or bushings etc. I have them in my barn. I'm trying to get one before the Creede trip.
|
|
|
07-22-2009, 01:04 PM
|
#7
|
Senior Member
Join Date: May 2006
Location: Houma, LA
Posts: 886
|
Quote:
Originally Posted by folivier
|
Yes Forest that is the multiplier that I have in my coach. You'll love it!
__________________
Tuga & Karen Gaidry
1999 Newell 45 w/2 slides
Coach #512
2005 Pilot
|
|
|
07-22-2009, 01:21 PM
|
#8
|
Senior Member
Join Date: Apr 2007
Location: Minnesota
Posts: 326
|
Diddo's from Wally, it is a great addition to our coaches. I also have not mounted it permanently and just plug into the air outlet at the rear of the coach. Just make sure that you get air lines that can manage 240 pounds and I double clamped them at all splices.
__________________
Wally and Phyllis
1988 Newell Coach #163
40' with tag 8V92
|
|
|
07-22-2009, 02:26 PM
|
#9
|
Senior Member
Join Date: Mar 2007
Location: mesa, az
Posts: 1,375
|
hi forrest,
the one you linked to is what mine looks like. when i get home tonite i will take pictures of how mine is set up. i noticed the other guys each have it done a little bit different. i am a find a deal guy and when i bought it i searched and at the time, it was the cheapest from newell.
tom
|
|
|
07-22-2009, 03:15 PM
|
#10
|
Senior Member
Join Date: Feb 2006
Location: Texas
Posts: 1,558
|
Forrest, I bought just my pressure multiplier from Newell, SMC part # NVBA1110-T02N. I paid $252.75, including shipping, several years ago. It is well worth the money. I just added two quick connects I bought from Home Depot. In retrospect, I would have used the standard screw in fitting on the 18" air hose that I now use to connect to the engine compartment air quick connect. At the time, I was using a 25' air hose on that end and wanted to be able to easily separate both hoses from the pressure multiplier. I have less than $20 in the fittings and the short air hose, which I purchased from Harbor Freight. I do recommend using a quick disconnect on the output side of the pressure multiplier.
As an aside, I found that the air quick disconnect in the engine compartment had a tendency to leak so when I replaced it, I added a brass shut-off valve between the air line and the quick disconnect. That has worked well. I leave the shut-off valve in the off position until I have the air hoses and fittings attached then turn it on. I turn it back to the off position before I remove the air hose.
|
|
|
07-22-2009, 10:30 PM
|
#11
|
Senior Member
Join Date: Apr 2007
Location: Minnesota
Posts: 326
|
I put a small water seperator in front of the input side to prevent any moisture getting into the multiplier which could easily get damage by moisture and I don't want to put any into the tires either.
__________________
Wally and Phyllis
1988 Newell Coach #163
40' with tag 8V92
|
|
|
07-22-2009, 10:35 PM
|
#12
|
Senior Member
Join Date: Sep 2008
Location: Thibodaux, LA
Posts: 1,221
|
I just ordered one from Newell, should be here by Monday. That'll give me plenty of time to rig it up and head for Creede on Friday!
Thanks for all of yall advice!
|
|
|
07-22-2009, 11:04 PM
|
#13
|
Senior Member
Join Date: Feb 2006
Location: Texas
Posts: 1,558
|
Great idea on the water separator Wally. I will have to add that to my rear air chuck. Man you guys cost me a lot of money.
|
|
|
07-23-2009, 01:52 AM
|
#14
|
Senior Member
Join Date: Mar 2007
Location: mesa, az
Posts: 1,375
|
mine is a NVBA1110-T02N which is a slightly different part number than michaels, unless he transposed a couple of characters.
the picture is below with the fittings i have on mine....
hope it helps the others,
tom
|
|
|
07-23-2009, 02:51 AM
|
#15
|
Senior Member
Join Date: Oct 2007
Posts: 279
|
Yep, looks just like mine. Some very good ideas from Wally and Michael on water input and connection and disconnection. Mine almost blows me into the engine when I go to disconnect the thing. I like what Michael has done.
|
|
|
07-23-2009, 03:24 AM
|
#16
|
Senior Member
Join Date: Mar 2007
Location: mesa, az
Posts: 1,375
|
mine doesnt move me at all. maybe you need to put on a hundred pounds or so.
tom
|
|
|
07-23-2009, 03:35 AM
|
#17
|
Senior Member
Join Date: Feb 2006
Location: Texas
Posts: 1,558
|
Yep, I mistyped the number (added an extra 1). I have corrected my previous post to avoid confusing folks.
|
|
|
07-23-2009, 04:38 AM
|
#18
|
Senior Member
Join Date: Feb 2008
Location: Riverside, California
Posts: 1,543
|
Tom, Michael.....I'm ignorant on this item....please explain for the uninitiated (of which I may be the only member here) what the air multiplier does, and why I should add one to my system......
|
|
|
07-23-2009, 05:42 AM
|
#19
|
Senior Member
Join Date: Feb 2006
Location: Texas
Posts: 1,558
|
Clarke, if you use the system to inflate your tires AND your tires are inflated to over about 110 psi you will find that it is a pain to use. The engine mounted compressor will take the system pressure up to about 120-125 psi and shut off. However, it will not kick back in until the pressure drops to about 110 psi. That makes it very difficult to fill the front tires on most Newells that need 120+ psi or even the drive axle which may require 110+ psi.
The pressure multiplier takes the air from your coach system and increases the pressure by approximately 50% so if your engine air compressor kicks in at 110 psi, the pressure available to inflate the tires is, at a minimum, 165 psi. That will easily inflate any of the tires on a Newell.
|
|
|
07-23-2009, 06:19 PM
|
#20
|
Member
Join Date: Sep 2008
Location: Elk Grove, CA
Posts: 91
|
Great discussion, I will be ordering one from Newell as well (they are currently backordered as of 7/23/09). Check out the picture on this link from the Bob Dickman Les Schwab website:
http://www.dickmantires.com/air_pressure/air_pressure.html
They sell the same unit (for about double the cost) packaged in a nice Pelican case. I will probably set mine up in a similar manner. They do have a few extra pieces though. There is a mechanism on the inlet air side, it doesn't look like a moisture trap. Anybody know what that is? On the outlet side it looks like they have added either a high pressure blow-off valve or maybe it is just a simple spring loaded valve to vent the air line between the unit and the tire after use. Any ideas?
__________________
__________________
Tim and Laura
2000, 45', Single Slide
Coach 541
|
|
|
|
|
Posting Rules
|
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts
HTML code is Off
|
|
|
|
» Recent Threads |
|
|