Do I have an air system leak?

[RBAJJK]

Hey All,

May be a silly question, but here goes. I have a 1996 Gulfstream Scenic Cruiser w/Spartan Alpine Chassis. I have the front dump switch on the dashboard, and know that it dumps all air when activated. The issue is when this switch is not activated, if I turn off the engine the rear will come down and the front stays up. Does this indicate a rear leak, or is this normal? The coach rides great and level when aired-up on the road. But if I stop for fuel, once full I have to idle for a couple of minutes so the back comes up especially with my bike rack and toad (they don't like sharp turns together if not fully aired - one will touch the other).

Any way for me to test for a leak?

Thanks as always.

[RBAJJK]

Hey All,

May be a silly question, but here goes. I have a 1996 Gulfstream Scenic Cruiser w/Spartan Alpine Chassis. I have the front dump switch on the dashboard, and know that it dumps all air when activated. The issue is when this switch is not activated, if I turn off the engine the rear will come down and the front stays up. Does this indicate a rear leak, or is this normal? The coach rides great and level when aired-up on the road. But if I stop for fuel, once full I have to idle for a couple of minutes so the back comes up especially with my bike rack and toad (they don't like sharp turns together if not fully aired - one will touch the other).

Any way for me to test for a leak?

Thanks as always.

[GaryKD]

If you lose all your rear air during a fuel stop, I would think you have a leak. That is a lot of air leaving in a short amount of time. You should be able to hear the leak and trace it by following the sound.

[RBAJJK]

Thanks for the reply, Gary! I do not lose all of the air during a fuel and coffee stop, but enough so the rear does come down. I'll try to listen for the leak this weekend. If that dash switch is not activated the front keeps all of its air indefinitely. I'll update after I investigate.

Thanks again.

[quikduk]

Brian, it could be several items in front of the rear diff that are leaking but from my recent experience, it is most likely the original air leveling valve.

These chassis of this period typ. have one for the rear air springs/bags and two up front, one for each side.

The factory LV's had the brass fittings threaded into the phenolic plastic bodies which had brass inserts. It was/is common for some to overtighten these and thus cracking the phenolic body of the valve.

You will have to either safely inspect it yourself or take it to a shop with either a lift or a pit. The change out takes 20 min. or so including cleaning and testing for leaks with soapy water. If you take it in, the valve installed should run right around $200.

The new valve (RideRite) is blue and can be used in horix. or vert. positions. The rear is a horiz. mount.

This is the one that retrofits for our older models.

http://www.ridewellcorp.com/air.shtml

http://www.anythingtruck.com/M...duct_Code=270-E12525

The second link shows the part numbers that this valve replaces.

There is still the possibility that your bags, lines, safety brake, pressure relief valve, or distribution ports or any of the hoses are leaking but that is why you need to check or have it checked with soapy water from below while it is aired up.

Be safe as you do not want to get squished if it comes down on you...and you will unless there is enough safety clearance if the entire systems dumps. It isn't a difficult repair. Just be carefull if you do it yourself.

I personally have the rear wheels on solid wood blocks, chock the front wheels, set the trans in neutral (Allison), set the brake, open the compartment doors on both sides of this area (gains about 3") and then while the coach is idling with my DW standing by inside at the DS seat JIC, I roll under on a creeper and spray soapy water on all of the fittings and valves.

The leak will show up as BIG bubbles very quickly. Identify the areas, roll out, shut off the coach, dump the air (the brakes require air to release the BIG springs inside the cannisters so once the system is "dumped", the coach should not be able to move) and then go back and replace the defective parts.

Again, this type of repair is simple BUT the safety precautions are critical to success. The new part(s) will have to be checked for leaks and tightened (if they do leak) with the coach completely aired-up.

If you do not feel comfortable or qualified to do this, take it to a reputable Spartan chassis shop.

[RBAJJK]

Quikduk,

I was able to check the rear air system today. Started spraying the soap solution on the valve first - but no bubbles. Using my best contortionist moves I decided to try to spray the top of the valve. While positioning my hand and spray bottle, from six inches away I actually felt air spraying on my hand. I followed the leak to a crack in the valve, near the bottom where a metal plug is screwed into the bottom connection. It is quite a leak, so you were right again......thanks again!

Of course, I neglected to find and write the old part number down, so I will likely go back tomorrow and try to locate it. I want to be sure I order the correct replacement. I do have a quik question for you. The link you supplied above has a part that refers to push-to-connect fittings. I know mine are threaded as I suspect yours were. Should this be of any concern? Is there some type of retrofit that is required - making my threaded connections, push-to-connect?

Thanks again as always.

Brian

[quikduk]

I was able to get the retrofit valve with screw on connections but I suspect that they are all gone by now. The new one is a push to fit type. Hopefully your lines are long enough that you can cleanly cut, debur and push into the new valve. If not, you will have to get some push to connect couplings and extra air hose.

This really isn't a big deal BUT you must correctly size the hose. They are usually color coded for sizing (red, blue, green etc.). I think the lines are blue but I do not remember what size they are and my MH is presently under 3 feet of snow...and we are supposed to leave IN it next Tuesday...

When you buy the P-T-C type valve, the shop should be able to tell you what size air hose goes to the bags/springs as I am sure it is standardized in the industry.

[RBAJJK]

To All,

I did order the valve as suggested above by Quikduk (thanks). Also ordered some replacement 3/8" replacement nylon hose from the same place - anything truck. The shipping for the valve was only about $10, then I went ahead and added 100' of the nylon hose and it only added $.50 to the shipping, so I bought both. The valve and hose were both a perfect fit, and given how easy the push to connect fittings were to use, I ended up with about 99.5' of leftover hose. Once I got the valve replaced I checked the hose valves and connections for leaks, all OK no leaks - it was 100% the valve.

Thanks again for all the help.

Brian

[quikduk]

Sorry for the late response but life has been hectic for a while now.

Glad the fix worked. I will be going to the PTC fittings and valve someday when the new valves fail.

The old ones had fixed alum. inserts in the phenolic resin body and the brass fittings were typically overtorqued in these causing the housing to crack.

I apparently got the last of the old style retrofit Ridewell valves. All of the new ones are the universal (vert. or horiz.) PTC one I listed above.

I will buy one and some hose for a spare JIC.

OAN, another spare part(s) to carry would be a serpentine belt and 36"L 1/2" breaker bar ($35), a diesel lift pump ($85) and spare fuel filters (primary and secondary - $25-$35) as sources on the road can be a bit sketchy and these can be replaces with hand tools but without the parts your ride is not moving.

Great job and congrats again.

Ken