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RAP1940 6 Pack Air Solenoids Rebuild Advice
#1

Howdy all,  this is about the hwh leveling system and not valid

I get calls and emails and texts several times a week on these valves.  as you know i sell rebuild kits for the valves that allow you to rebuild one entire 6 pack for about the cost or less of one single complete new valve.  

i wanted to share what i have learned about these simple valves and give some tips on rebuilding and installing them.  

what i have to say is based on helping alot of people with these things, and having rebuilt and installed them on many coaches.  

there are several ways these things can leak and fail.  that said,  these valves were meant for a zillion cycles.  a zillion cycles in a CLEAN air system, which our coaches are NOT.   

how can they fail.....

1.  the seal on the plunger inside the stem that rides on the orfice gets compromised causing the valve to leak.  causing the bags controlled by that valve to deflate.  the seal most likely gets compromised by dirt or rust or debris in the air system that gets inside the valve between the plunger seal and the orfice, causing to to keep it partially open and or scored.   the spring that holds the plunger on the orfice is only strong enough to seal it with no debris.  if you take the valve apart and see moisture and junk inside the valve body, it is possible that could, and i say could cause an issue.  

let me give you a scenario where the rear raise valve is leaking by alot.  you are driving and the raise and lower valves are not activated, but the rear passenger side raise is leaking.   now the passenger side rear bags are getting air from the valve leaking,  and the ride height travel valves are supplying air to the ride height valve and if the raise is leaking enough to overpower the ride height valve letting air out, then the coach will raise up on the rear passenger side while you are driving.   dont ask me how i know.....it happened to me.   

it is also possible that the plunger seal has gotten scored by the orfice such that it doesnt seal all the way when not static (with the spring holding it down, not energized)  the first picture below is a plunger with a seal that is fairly well deeply grooved.  the orifce has sharp edges to help it seal. 

another scenario is if you are parked overnight and you have leveled it and do not have it on auto level.   a 95 newell was here at my place this week where his passenger side rear would drop in a few hours.   i took the six pack apart and found that there was a problem with the lower valve on the passenger side.  it had a mangled outer O ring on the valve body that was letting air escape slowly.  that valve had been screwed into the manifold wayyyy too tight and it gouged the O ring.  since i had the valve apart, i also put new plungers and springs and all new o rings in it since it was apart.   these valves do not need to be much more than slightly snug when you install them.  the next picture is of the O ring that goes in the outer bottom of the valve body.  this is the one that was leaking.  

another scenario is what i have seen a number of times.   this happens when someone is installing the valve.   and comes from over tightening it.  the valve bodies i have seen in several materials.  the older ones are mostly brass.  the newer ones seem to be mostly aluminum.  both can have the same issue if you over tighten them and you would think that if you just rebuilt the valve that there would be nothing wrong.  

btw, all of this assumes you use some type of oring grease on the 2 orings that touch the six pack body from the valve.  

this next picture shows a valve body that has been overtightened.  it distorted the inner 0 ring groove such that it broke loose at the bottom and now has a hole that can leak by.  this one is brass.  it happens on the aluminum ones too.  

btw, the brass or aluminum valve bodies are exactly the same.   just a different supplier.  the stems that hold the plunger and spring are all the same.  the 4th picture is of a 6 pack that has valves that have the brass body and the ones in the travel position on the right are black aluminum.  

when you get into the early 90s and back they used KIP valves that had a coil that was completely covered with a metal case.  the parts are interchange with that valve and the newer style.  the next two pictures show that coil.  some of the early kip valves had a slightly larger orfice.  since the rear of my 02 comes up very slowly, i put a larger orfice valve in the raise position on both sides in the back. 

i have found that there was batch of valves that were labeled rap1940s that were completely different.  and i have found that they failed alot more.  they had a silver aluminum body and a different style plunger and spring and they do not work with any of the parts that i have.  i dont know that newell used them but other brands certainly did.  but i think for a very short time.  

these things are pretty simple.   as far as i have seen, the 6 packs in newells all have the same valve location placement.  so i have attached a highly refined sketch.  on all that i have seen the travel valves are nearest the firewall that the manifold is mounted too.  

o rings are cheap so always replace them.   the stem comes out easily is you have one of the spanner wrenches.  if not, then use a vice on the body and gently use pliers on the stem.  the stem is hollow for the plunger to go in so dont distort it.  

btw, NO o ring grease on the inner oring between the stem and valve body.  you dont want to junk up in the inside of the valve where the air flows.  

the coils almost never go bad.  

i take a felt tip maker an mark on the 6 pack manifold what each valve is doing.  just so it is easy to remember next time.  

well, thats my 2 cents worth.  remember every newell is different so apply common sense to if any of this for sure applies to your coach. 

foretravel used the same valves as did alot of the SOB's.   

i just tried to cover some of the things, there is certainly more scenarios.  

be sure to the get the right coils on in the right positions.....and use o ring grease....clean them up when you have them apart and dont overtighten when you put the valves back on.   

tom


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2002 45'8" Newell Coach 608  Series 60 DDEC4/Allison World 6 Speed HD4000MH

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#2

Thank you Tom! I have ordered one of your kits and when I checked it out, felt like it would be an overwhelming task to rebuild these things. So far (knock on wood) mine are working as intended. The HWH leveling system is one of the few things left that I have not really understood well on my coach. Next is the basement a/c units which 2 have failed even after a condenser fan motor and caps have been replaced last year. I gave up on those and have no idea what to do next. (No roof airs for me as I am a stubborn bastard!)

--Simon
1993 8v92TA #312
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#3

Tom,
Great info thanks for sharing! Question; do you remove the manifold and take it to your workbench or remove the individual valves in-situ?

Steve & Doris Denton
45' Newell #525, Bath & Half....sold
37' Country Coach, Tribute....Cat C9, 400 hp
2014 Honda CRV Toad
Summerfield, FL
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#4

I leave the manifold in. Taking the valves out a pair at a time gives you room to get at them

1 to 2 hours to label, take them out. Rebuild and reinstall. I take the coils off and leave them hooked up once I have labeled them

The front manifold is harder cause of where it is

Tom

2002 45'8" Newell Coach 608  Series 60 DDEC4/Allison World 6 Speed HD4000MH

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#5

The front is not so much fun but the rear is a piece of cake I used both kits so should be good for awhile but I will be out to visit nephew in Surprise AZ this upcoming 4th of July, if your going to be around I would like to meet you in person and purchase another kit for just in case.

1999 45'  #504 "Magnolia"
Gravette, Arkansas
1996 40 XL Prevost Marathon 
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#6

We should be home. Keep in touch as it gets closer

Tom

2002 45'8" Newell Coach 608  Series 60 DDEC4/Allison World 6 Speed HD4000MH

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#7

Tom,

On my coach #606, I am having the rear of the coach completely deflate within a few hours of parking. I’m also not having much luck with the leveling controls as I can’t get the travel mode button to stay lit, and I feel that the coach sits low in the driver side rear almost all the time.
My first plan will be to rebuild the solenoids in the rear. How do I go about buying this kit?
Any idea if rebuilding these will aid in the travel mode on the control panel functionality?
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#8

there are a number of things that can cause your problems. you have to start breaking it into chunks and eliminating things. my valve rebuild kit would make the valves as new. is that your cause of dropping in the rear.....cant say. that would means both lower valves are leaking by. possible.....but usually just one. it would not fix your travel mode issue. you could have bad fittings, lines, airbags etc.

the rear six pack is the easiest to do because it is easy to get at.

email me at [email protected] and i will give you the scoop on getting the kits from me.

tom

2002 45'8" Newell Coach 608  Series 60 DDEC4/Allison World 6 Speed HD4000MH

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