Door Solenoids and Poppers

I bought a great shaved door handle kit off of ebay (seller doesn't exist anymore). It came with two 50 lb door poppers, two 45 lb solenoids and all the components needed to make it work with my existing burglar alarm.

Audio Adapters 50 lb kit

Door Poppers

Door poppers are used to pop open the door once the solenoid unlatches the door. The solenoid electronically takes the place of the door handle. The door popper gives the door the push to open.

Typical Door Popper

The door popper is basically a spring loaded cylinder that is compressed when the door is closed and the spring provides the push to open the door. Unfortunately, I ran into a problem where the protective rubber head of the door popper is too large and jammed between the door and the door frame when the door was closed. It was difficult to open with the existing door handle! Since I had drilled a big hole in the door frame for the door popper, I removed the spring and screwed the cylinder all the way in and mounted it in the new hole as a conversation piece.

Door popper disabled and installed just to cover the new hole in the door frame..

As I found out, the door latch mechanism on the 54 Pontiac (and Chevys) automatically pop open the door when used. You don't need the door poppers!

Solenoid Installation

I installed the solenoid in a convenient place, in the bottom of the door in the access opening. It has a cover plate that will cover it when it's all together - not to mention the door panel itself. It is important to make sure that the solenoid does not interfere with the window regulator so check for clearances.

Good picture of overall installation!

The solenoid is mounted with 4 bolts at the bottom. The pull cable from the solenoid is routed through the door metal by a bicycle brake cable (more on this later!) It curves to line up with the latching mechanism. Notice that there is a a pull rod going to the inside door handle (details further down).

Closeup of soleniod

I found that the hook that is screwed into the top of the soleniod would loosen quite easily after a couple of actuations even with a locking nut! A dab of locktite and one problem solved. If you look closely, you'll see that the pull-cable is not tight to the solenoid. I found that the solenoid need a little slack in the cable to get moving. I found that about 3/8" worked great. By the way, you can test the solenoid action with a battery charger but it will be quite weak compared to actually using a battery. With my 6 A battery charger the solenoid would work intermiddently. With a 12 V car battery, it would slam the latch mechanism with a resounding thud!

Dual Latch Slide

I wanted both the solenoid and the interior door handle to open the door. I threaded the original latch opening for the door handle pull rod to fit a hex head screw and used a locking nut on the other side. I drilled a hole through the hex head bolt's head to fit the solenoid pull cable through.

Tip: file a flat spot on opposite sides of the hex head screw, it'll make it way easier to drill. Drill from both sides rather than trying to drill straight through. If you try to drill straight through from one side only, you'll break the drill bit when it goes through into the hex opening (guess how I know!).

Closeup of door latch modifications

I modified the door handle rod by trimming it shorter and welding a slotted plate to it. The slot is positioned so that when you pull on the door handle rod (like when opening the door), it immediately pulls the latch. The slot is to allow the solenoid to pull the latch without engaging the door handle mechanism. When the solenoid pulls the hex head bolt, it slides along the slot. Simple to make! Try to make the cable pull as close to parallel to the door handle rod for best operation.

Instead of the cable that came with the kit, I used a bicycle brake cable. It had a much better sheath that allowed the cable to slide smoother and one cable cut in half worked for both doors - price $2.99! I strung the cable with the stop through the hex nut, sheath and then crimped it at the solenoid. I used a cable clamp to make sure that the cable bent at a gradual angle.

Running electrical wiring

I tie-wrapped the wires at the solenoid to the solenoid to keep them out of the way of the window regulator and then routed them up to the top door hinge. I drilled a hole and used a rubber grommet through the metal big enough for a 1/4" plastic wiring harness to fit tightly through. The wiring harness then was tie-wrapped to the door hinge with enough slack left so that it will bend with out stretching or breaking when the door opens and closes. It was tie wrapped on the inside of the hinge as there was no clearance on the top or bottom. I used a black tie-wrap and cable harness so it all blends in.

Closeup of door hinge wiring

I ran two wires from the solenoid: a black 18 gauge for ground and a red 18 gauge for the solenoid +12V. There isn't a good ground between the door and the body. Relying on the hinges for a ground path is not a good idea.

Car Alarm Remote Control

Most car alarms have an auxilary output and an extra button on the remote to activate it. I've wired up the driver side relay to my car alarm's auxilary output. Now I can remotely open the door like magic. It is similar to remote door unlock but the door pops open. It impresses the hell out of people. The passenger side relay is wired to a hidden waterproof switch for when I lock the remote in the car which happens and is very easy to do. So rather than smash a window, I can still easily get in the vehicle. Trust me, you WILL lock your remote in the car. Most of the time, I just leave the windows open!

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Copyright Aug 2011 Eugene Blanchard