Propane Problem Resolved - Regulator Leak

Rear bumper removed to gain access to the propane system

I opened the propane tank shut-off valve and I could hear a "hiss" when kneeling at the shutoff-valve.  This indicated a nearby leak in the system.  Climbing  under the Roadtrek I could barely see the regulators, but could not reach in or determine the source of the leak.  In fact, I used a dentist's mirror to see the regulators. In 2014 the Roadtrek had a propane issue. We could smell propane when at the rear outside of the vehicle. This was repaired by the dealer "under warranty". However, the corrugated black plastic protective shield was not fully closed. Which was why I could see the regulators while on my back and under the vehicle.

I decided to think about the possible solutions.  Obviously, I needed to get to the regulators. I suspected the accessory regulator diaphragm had failed. But there was nothing to do until I could get access, nor could I locate the specific source of the problem until I could gain access.

I had several choices:

1. Take it to a dealer.
2. Do the work myself.
3. Take it to another repair source and share the work.

I pondered the best approach.  I crawled under the Roadtrek a couple of times and concluded there were two methods to gain access to the propane regulator area:

1. Remove the tank and propane components.
2. Remove the rear bumper, thereby exposing the propane components.

The rear bumper of the Roadtred is a fiberglass shell bolted to the original Chevy 3500 steel bumper.  The fiberglass covers the steel bumper which is not visible from the rear.  The Chevy bumper is attached to the chassis with eight bolts.  The fiberglass shell also has two plastic straps attached to the body, acting as stiffeners.

I decided to go to a local repair shop I use in Tucson and discuss the removal of the bumper with them.  I described what I wanted and how the bumper(s) were attached to the Roadtrek frame.  They concluded that they could remove the bumper.  That was the approach I chose.  They would remove the bumper, I would deal with the sourced of the propane issue and then they would re-install the bumper.

The labor cost to remove and re-attach the bumper was $119.43, including Tax.  My material cost was about $10.  It included yellow (natural gas/propane) sealing thread tap, a 1/4 NPT brass cap, 1/4 NPT brass plug (I wasn't  sure which I would need). My material also included Velcro tape to attach the corrugated protective cover over the regulator.

The bumper was removed and the top photo shows it in the garage.

Accessing the Propane Tank and Regulators

The next photo shows the tank and regulators exposed by removal of the rear bumper.  There are two regulators:

1. Chassis regulator - two stage
2. Accessory (grill) regulator - single stage, 10 PSI.

I suspected the single stage regulator was the source of the leak. 

As can be seen in the photo, this model Roadtrek (2013 210P) has the regulators installed above the 10,000 lb. hitch frame.  Because the regulators are sandwiched between the bumpers and the propane tank, there is absolutely no access from below with the tank and bumper attached. 

Rear Bumper Removed, exposing Propane tank and Regulators

To check for the source(s) of the leak I made a soapy mixture and sprayed it on the piping and on the weep hole of the 10 PSI regulator.  These regulators have an internal spring-loaded diaphragm. The diaphragm can fail and if it does, propane can leak to the spring side of the regulator and from there to atmosphere via a pressure weep hole.

I sprayed the mixture on the regulator, opened the propane valve slightly and the leak became readily apparent, as can be seen in the photo:

Propane Leak at Regulator Sprays water

Remove or Replace the Regulator?

With the source of the leak identified I had two choices:

1. Replace the accessory regulator.
2. Remove the accessory regulator.

Because this was the second problem in this area since 2014 and the fact that I have never used the accessory propane connection I decided to remove the accessory regulator and install a brass plug or cap, as required.

Removing the regulator and capping the propane piping

I removed the regulator and a brass street-elbow and attempted to remove a short fitting but it was really stubborn. I was going to install a plug in the tee, but that wasn't possible. So I decided to install a cap instead of a plug.

Remove the accessory propane hose clamp

Remove the Accessory Regulator and hose

Regulator and hose removed

Brass cap installed with yellow gas sealing tape

I reinstalled the hose clamp using the original screw. That was the easiest method to seal the hole. I then removed a street elbow and installed a 1/4 NPT brass cap using yellow gas sealing tape; that is very important. The proper seal must be installed.  White Teflon tap must not be used. After tightening the cap I opened the propane valve and applied a liberal amount of soapy water to the existing Tee and the new cap.  No leaks were detected. 

Testing the Propane System

To test the system I lit the range top burner.  Success.  I then returned the Roadtrek to the shop so they could wrap the propane dual-stage regulator with the original plastic protective "box" using velcro strapping I provided.  They then re-attached the bumper.

Range top works again on propane

Final Assembly

There were two plastic stiffeners to hold the left and right caps of the fiberglass bumpers. I drilled out the pop-rivets and re-attached. One had been previously damaged. I replaced it with plastic strapping material I got at the hardware store.

Final Step

The next step will be to put fresh water in the tanks and turn on the hot water heater.  That will be tomorrow.

Additional Information - Rusty propane tank

You may notice that the propane tank is white but dirty.  In fact, when I had the first propane issue in 2014 I crawled under the tank and noticed some pits and dings which were rusty.  I assume this was caused by stones and other road debris being tossed up and onto the tank.  I cleaned the tank with a solvent and then applies white Rust-o-leum paint.  The tank still looks good.  I am a firm believer of Preventative Maintenance as a means to minimize breakdowns.

Original material http://roadtrek210.blogspot.com/ (c) 2021