Venting Boot Layout and Install
(Click any pic for an enlarged view)

In the beginning of this project I did all the planning, design and layout. Then took it all to scale drawings. This allowed for many pitfalls and problems to be worked out before I started. Using AutoCAD, drawing to scale never lies.

There are some NFPA 52 rules regarding venting CNG and vent booting. From what I understand, you can get away with wrapping a plastic bag around the valve assembly and venting it to the outside. Well that is not going to fly here. We are going over the top.

This is the layout of the tank configuration showing the vent boots, hoses and connector fittings. As you can see all body panels, supports and equipment can be see in color. When I started building the vent system I saw a more efficient way of routing the hoses and lines. The below pics reflect the modifications.

Here is what we are starting with. Notice the rubber boot on the far tank. You guessed it, salvaged from a Cavalier along with other fittings, clamps and connectors.

I needed some way to provide an air tight seal between the floor and the vent hoses and got an idea from this rubber pipe cap.

First I needed to drill a hole in it large enough to allow a bulk head fitting to pass through.

Then fabricated a funky washer to fit inside the cap and also pass over the fitting.

Three holes were drilled to allow self drilling metal screws to hold the cap to the floor.

Another pic of the washers.

Next I needed an adapter from the cap to the hose. This was accomplished with some PVC fittings, glue and a little lathe work to mate the cap and hose.

Another pic of the adapter assembled and glued together.

A little paint on the the viewable surfaces and we are done. I needed three of them to do the job.

Here is an semi exploded view of how the parts will fit together.

Some preliminary fit up to make sure things work right.

Here the PRD vent pipe, boot, adapter and cap are fitted up. So far so good.

At this point I decided to route the 1/4" 316 Stainless Steel tube. A #4 JIC x O-ring boss fitting is installed in the HPL. I used a 37° flaring tool by Rigid Tools to flair all the tube ends.

316 Stainless is so hard that I ruined many tube flares until I developed a workable way to flare the tubes. Now every flare is perfect. Here more fittings are installed and the tube from the front tank is connected to the rear tank.

The tube from the rear tank ends up here at the bulkhead fitting in the floor.

A healthy dose of black silicon rubber, three stainless steel self drilling screws and the floor seal is installed.

A finished view of the seal.
     Now on to the rear tank. The PRD vent pipe created a problem. The pipe has clearance, however the floor seal landed on part of the support pad. Moving the seal rearward put it in the under floor channel. Ugggg

So to get a point to work from. I drilled a hole in the floor to get my floor seal clearance. No matter what I did I could not get the existing pipe and fitting to bend into place.

So I cut the O-ring face seal fitting off the pipe and lathed off the weld. Then custom bent a new tube and TIG welded the fitting back on. I was surprised at how nice 316 stainless steel TIG welds. Like melting butter.

Here is a view if the new PRD vent pipe and associated seal hardware. A floor connection is all that is needed and we are done.

Here I am coating the O-ring that fits on the face seal and PRD fitting. Any time you are messing with O-ring boss of face seal, you should dress the seal with vasoline.

Here is a close-up of the floor seal connection.

Now it is time to do some electrical connections for the HPL's. The electrical connectors and boot seal plate are salvaged parts. I picked up a ton of assorted size black wire loom of Ebay to make the job look OEM.

Here I am assembling the two HPL wiring harnesses. Soldered joints and shrink tubing is a must. In fact I purchases a bunch of shrink tubing packs from Harbor Freight cheap.

Here is a shot of the rear tank electrical routing. Notice the rubber plumbing tee. Nothing to high tech here.

The male and female electrical connectors mate here. The OEM parts make for a clean water tight connection..

Here is another shot showing there over all routing.

and another shot going rear to front.

another shot going front to rear.

Opps I forgot. The rear tank HPL has only one inlet tube and two inlet ports so an O-ring boss plug needs installed into the extra open port.

An easy install.

Well this is the overall final view. Hope some of this helps anybody tackling a project like this.