Fuel Injection: How It’s Going

I’ve got the week off from work to burn up excess PTO time so I’ve been focusing mainly on the EFI install and procrastinating by tackling some smaller projects on the side. The EFI install is intimidating because it includes lot of things I’ve never done before and presents some mechanical problems that are proving difficult to solve. The instructions begin with the simple task of installing a fuel pump and two fuel filters in between the gas tank and the engine. This also includes a return line, something modern fuel injection needs, but my truck never came with. So that required dropping the tank again, drilling a hole somewhere in the tank, and plumbing a new line. Another complicating factor, as mentioned earlier, was that there’s little to no room in between the outlet on the tank to the engine compartment, which made the fuel pump location a huge question mark.

Dropping the tank was easy; I’ve already done that once. But when I drained the tank, I found a pint of what I can only assume was water, which was very disturbing. I know I emptied this tank out completely before I reinstalled it and I know I capped off all of the inlets so I don’t understand where this water came from. What I’m most concerned about is that I’ve been trying to start it and I’m afraid I may have hydrolocked the engine by squirting water into the cylinders instead of gasoline. After some deliberation, I’m going to continue with the EFI install on this engine, assuming I haven’t bent any pushrods, and we’ll see.

After the tank was down, I measured and test fitted and measured again and found the best possible place for the return line, right next to the sender hole at the top of the tank. This is the only place I could get fingers inside to tighten any bolts. I filled the tank with water, drilled a pilot hole, and then used a stepped bit to widen it out. The fittings that come with the kit were all aluminum, so I needed a wire to fish them back out after dropping them in the tank the first fourteen times, and found that using the wire was the best way to help guide the parts into place. I also fabricated a bent wrench out of 16 gauge steel to help tighten the fitting up inside the tank. After flushing it out with more water, I installed the return line and bench-tested the fuel sender, but wasn’t getting reliable readings. When I got the truck, the fuel sender actually worked, but I’m not sure what happened after I pulled it out. My multimeter is the $9 Harbor Freight special, so I decided I needed to upgrade that to something a little more legitimate.

Underneath the truck, I found the best possible place for the fuel pump and pre-filter was on the inside of the frame rail. That was all still filthy, so I scraped and wire brushed it, then painted it with encapsulator. The only way I could figure on routing  the fuel line was to direct it backwards to the inside frame rail, do a 180° curve to the pre filter and pump, then go up to the engine bay. I ordered aluminum fuel hose for the bends because I didn’t want the hose kinking up over time and restricting the flow.

While I was puzzling over those problems, I was fixing smaller things like a sagging driver’s door. After lifting it up with a bottle jack, I loosened then tightened the hinge bolts and it closed cleanly. Then I bent some 16 gauge steel into an L shape, drilled it out, cleaned it with a file, and used it as an under dash bracket to install a USB charger.

Thursday started out being a gloomy, rainy day, but after about 2 o’clock, the weather cleared, the sun came up, and it warmed up to about 75°. In the morning, I drove up to a locksmith in Towson to have them look over the rear door handle and help me understand the problem I was having with the new lock cylinders falling out of the assembly. The guy behind the counter was super helpful, but he couldn’t figure out what we were missing. After talking it through with him, he agreed that I needed a spring loaded retainer clip at the back of the regular door handle lock cylinder, and that the ignition cylinder wouldn’t work in the door. I was hoping I would have more answers than that, but he got me to thinking about a way to solve the problem. I stopped off at Harbor freight for a better multi tester and then headed back home.

I took full advantage of the afternoon, warmth and pulled the old carb off the engine, cleaned up the intake, and dropped the sniper in place. After reading and rereading the installation instructions, I started roughing in the wiring in the engine bay to begin to understand where things need to go. Alternating between the engine and the frame rail, I sorted out most of the main electrical harness and crimped and soldered leads for the positive and negative battery terminals aligned for the controller is fished into the cab, and the main fuse and relay harness is roughed in on the firewall. I did find that the temperature sensor included with the kit is one size larger than the threaded hole in the water neck. I have a spare manifold sitting on the floor of the garage that I can examine to see how hard it would be to drill and tap a wider temperature sender. Of course, I’m of getting metal shavings in the engine, so this is the nuclear option. The other installation issue is that both the fuel inlet and return outlet on the carburetor are right up against the water neck and coil so I put a pair of 90° fittings on my parts list.

Under the truck, I finished the fuel pump install and with a handy delivery from Amazon, I had 10 feet of coiled aluminum fuel hose in my hands. It just so happened that they had coiled the inside loop at a little less than 6″ so all I had to do was cut off a section of the inner coil and I already had a clean 180° bend in my hands. I flared the ends and installed that, then started looking for a way to get the fuel line to the inside of the frame rail. I found a factory-drilled hole large enough to feed another 90° bend just above the spring perch and threaded an another length of aluminum through to join up with the rubber hose. It feels Mickey Mouse, but I think I’ve solved the fuel routing problems and I was happy that I was able to use the brake flare kit I bought two years ago on this aluminum. Then I used a punch to put a divot in the exhaust pipe, drilled out a hole, and installed the O2 sensor. The clamps provided with the kit were too small so I used a set of pipe clamps from my bench for the time being until I can get factory clamps in hand. When I get those I’m going to pull the 02 sensor back out and wire-brush the pipe for a better mating surface.

I got back up and worked in the engine bay on the wiring until it got dark and then brought some parts in to the workbench in the basement. The first task was to modify one of the door lock cylinders to accept a snap ring at the very back using a Dremel. I carefully cut a channel out of the rear of the cylinder and trimmed a snap ring down to the same diameter. Inserting that into the channel and inserting it into the button, I used a pair of snap ring pliers to widen it out so that it stayed in place but spun freely. Reassembling the handle, it finally worked as designed and I had something I could put back on the truck.

Next, I spent a good bit of time testing the original fuel sender with the new multimeter and found that it did work, but that was dependent on the angle of the float arm. Sometimes it made contact with the rheostat and sometimes it didn’t. Doing a little more research, somebody on the Binder Planet posted that the sending unit for a ’57 Thunderbird would work with a little bit of modification, so I put that on the parts list.

I’ve been itching to just get it done but have been practicing my patience as much as possible, and as of Friday I’m pretty happy with where I’ve gotten to. The biggest hurdles now are to understand the wiring setup, and I’m going to take my time to understand what I’m doing before I start hacking things up.

Weekend Recap

Looking through the Sniper install instructions, it’s looking like the most complicated part of the whole thing is going to be dealing with the fuel tank. Essentially, I’m going to need to empty it completely, drop it again, let it dry out, fill it with water, and drill a hole in the top for a return line. Fuel injection requires a return line to the tank for somewhere to put the extra gas, so I have to sort that out. Thankfully, the kit comes with all the hardware required, so that isn’t an issue.

The next puzzle is figuring out where to put the fuel pump and prefilter. Because the fuel tank is under the passenger frame rail and the fuel outlet is directly behind the passenger wheel, the fuel line routes up through the passenger wheel well and up to the fuel pump, only about 2 1/2 feet in total length. The pump and prefilter aren’t small, and when they’re mounted together they’re about 18″ long. I really don’t want to mount the fuel pump right next to the wheel, so I’ve gotta find a different place to put it. Ideally, it would go inside the frame rail, but that means I have to reverse the direction of the fuel outlet, and find a way to loop the fuel hose around without kinking it. The extra added problem is that the exhaust pipe is on the passenger side of the truck, about 8 inches away from that frame rail, so whatever goes on there needs to have heat shielding.

The obvious solution to this whole problem would be to cut the receiver hitch off the back of the truck and hang a new gas tank under the center of the rear floor. Of course, I’d have to figure out how to plumb a new filler line and solve a bunch of other problems that I’m not ready to face. So that’s out.

While thinking all of the stuff through, I scraped and wire brushed the inside of the frame rail under the passenger side, hit it with rust converter, and then coated it with rust encapsulator. Both frame rails need this treatment, as I’ve done almost all of the outside edges, but because it sits so low to the ground, it’s really hard to get to the inside.

Stalling for time, I spent Saturday afternoon trimming out the already butchered original radio faceplate for a single DIN-sized radio  head unit from the Scout. Then, I repaired the wiring and mounted it in the truck along with a set of old school carpeted truck boxes we got from the repo lot thirty years ago.

On Sunday, we had plans to help our friend Brian install a two post lift in his new garage across the river in Chestertown. I met up with Bennett at a park-and-ride where he was waiting in his 67 Mustang with a seat full of parts and a warm coffee. From there, we caravanned across the bridge to Brian’s house. The plan was to drop the Mustang off at Brian’s so that he could install electric steering in the Ford like he did in his Scout 800.

After getting a little coffee and taking the tour, we started by sorting out all of the pieces and parts of the posts of the lift. We hefted  the first post onto dollies and moved it into position. With three of us, it wasn’t too difficult to push it up and sit into place, and Brian drilled the holes in the concrete to set it. Thankfully, the concrete only got poured a year ago, so it was easy to drill into. Then we moved the second post in a place and assembled the crossbar to hang between the two posts.

The weather was absolutely perfect for working outside and by lunchtime I had changed into shorts. The instructions that came with the kit were lousy, and didn’t explain which hardware went to what. This would not have been a problem if all of the hardware was the same size, but we had to guess between sizes for different applications. Once we sorted all that out, we hung the equalizing cables, electrical line, and hydraulic lines. While Brian was sorting out the wiring for the hydraulic pump, Bennett and I hung the four arms off the lift shuttles and set the pads in place. We left the entire thing anchored in the ground and ready for electrical hookup, which Brian is probably going to finish this week.

Bennett and I packed up my Scout and we headed back west with the sides rolled up in full Safari mode, enjoying the cool evening air. We stopped for a tailgate dinner of gyros right before we hit the bridge and made it back to his house as dusk was falling. I got word in his driveway that my niece and nephew were waiting with the girls at our local ice cream stand, so I hightailed it back to our neighborhood for a chocolate shake with the family.