Need some advice on Gas Line Clearance from the Exhaust System. If I route the gas line along the inside at the bottom of my frame, using a Stainless Steel Heat Shield with about 1/4" aif gap, I will have about 1" clearance between the heat shield and the exhaust pipe/ header connection. I can also add some Heat Shield Tape or Thermal Sleeving or Reflective Heat Shield Sleeving either on the outside of the heat shield or on the inside. Will this be adequate? The only other options are : 1) Run the gas line inside the frame. This doesn't seem like a good solution from a maintenance or safety point of view. 2) Run the gas line along side the engine (still close to the pipes) or 3) Use a electric pump and run the line up the back of the engine. Would like to keep the mechanical pump. The attached diagram is a cross section of the problem area and measurments. A nailhead under the hood of a Model A sure makes things cramped. Thanks for the help. Canuck
On my car I did it on the inside of frame. I was worried I'd crush it on the bottom. Different car though. Headers do get hot.
My cutl*** fuel lines are ran thru the frame. Was like that from the factory. You definitly dont want it to get hot. It will cause vapor lock and your car will quit going down the road.
that's close , you may be OK with the heat shield, maybe not....i'd feel a lot better if you had 2" or more
Inside the frame. Why be different?. If your frame is boxed, fab the line where it can be fished through a hole big enough for a grommet.
36 - - 2" just isn't a option, I wish it was. If I run it outside the frame it will be exposed to anything thrown up by the wheels and quite visible. The top of the frame is taken up with fenders (ya, I'm running full fenders on a A coupe) so options are limited. 29 - - so if you run the line inside the frame (mine is 2x5x.125 rec tube), a couple of holes for access, a grommet at each end, BUT do you clamp it in place as well? Have to run about 4 feet from the fuel pump to the location of the fuel filter mounted on the frame. So tell me again, who's idea was it to put a nailhead in this thing! Thanks Canuck
actually , on my full fendered `28 tudor i do have the fuel line on the outside of the frame high up on the frame rail just under the fender. just in the area of the exhaust , then the line tucks up under the frame right behind the tierod/drag link. i have saddle tanks and it was a short and straight run from the p***enger side tank. you can't see it at all , and i feel the 4-bar gives it some protection from road hazards yes , a 4-bar.....the ch***is was built in 1985
I'd have to think it over, several options, but the first one that comes to mind a straight run with bulkhead elbow on in and out, then pump that expanding foam in after the plumbing has been tested for leaks. That would serve the same purpose as clamping. Another way, seems that one support in the center of the run would be sufficient. A hole, with a standoff going in and gripping the line.
29 - - Slightly off topic, but I would be leery about using that injected foam. I think there was a posting a long time ago either here on the HAMB or on RRT about a motor home with the foam used for insulation and the moisture that was trapped between it and the metal and the resulting rust. Also saw the same thing at a neighbours with a foam insulated motor home, lots of rust on panels that had the foam against them. Anyhow, back to the subject at hand. How could you install a steel gas line inside a rec tube frame to a bulkhead elbows at each end? Not able to get at it inside the frame. The more I think about your idea of running it inside the frame, the more I think the advantages out weight the disadvantages. Maybe some preformed bends where the tube would go into and out of the frame, a bit of a bend inbetween to allow it to slide through the frame. A couple of clamps screwed to the frame along the line of electrical box clamps that fasten to the box and clamp the wire, would probably have to be made but wouldn't be the first thing that i've made for this beast. 36 - - Sweet coach, wish mine looked a fraction as good. Will be keeping your solution in mind if this inside the frame ideas doesn't pan out. Canuck
What I meant was elbows with grommetts, not the cl***ic 'bulkhead' fitting. I would prefer foam to having the gas line rattling around in there un-supported, drill a couple of little drain holes in the bottom of the frame. Unless it's a trailer queen, the heat from headers will keep it dry.
Had the same problem on my build. After experimenting with several possible solutions, I opted to run the gas line on the BOTTOM side of the frame rail -- simply because it was easier than cutting holes in the rectangular tube ch***is, fitting grommets, fishing tubing thru, etc. I've driven it about 3,000 miles without incident. While the odds of something striking the bottom of the frame rail and crushing the gas line are certainly greater than zero, so are the odds that you'll be crushed inside the cab by the debris of a rouge satelllite falling from orbit. The question isn't one of whether something is possible -- it's a matter of whether it's probable. Keep it simple, dude.
MY fuel line is about 1 1/4 from my manifold .I made an aluminum heat shield and put it half way between the two ,so far it has worked good. The air gap will let air move through to keep it cooler.
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