Most of the heat is transferred to the fuel as it passes near the exhaust manifold and front of the cylinder head, so if you've already got a hose-over-the-valve-cover setup, you should be fine (but I would definitely replace the hose with the fuel injection variety for safety with today's gasoline.)

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

thanks

Sorry dan but i have to disagree with all this fuel line crap. It is a proven fact that heat rises, all this does is put the line on top of the stove, sort to speak. Anytime you park a vehicle for 5-20 minutes, all that heat will go up and where is your fuel line? Not only will the line get heat soaked, but the Carb as well. The design of the / I think is poorly done with the intake sitting alond side/ over the exhaust doesn't help much either. Sure it help with atomazation, but that's it! With the so called gas that the Oil Companies pawn off on us today doesn't help this problem any better. I have done this mod and hasn't done a thing to help correct or improve my problem any more than leaving it stock. The only other plan that I can do is make a heat shield for the Carb, insulate the fuel line from the pump, and/or wrap the exhaust manifold with hedder tape. I would love to see your proof that this method works. What studies have you had done to give you the authority to say that this is a sure fire fix? I'd love to see it, otherwise this is just another snakeoil fix that you shouldn't be telling these younger folks to do.

69a100, you seem to be just about the only guy repeatedly insisting this can't possibly work. It's worked great on every car I've done it to (still need to do my '73; I promise to let you know in public if it doesn't fixthe hot-restart/hot idle problem like it did on my '71, and my '62, and my '65, and…).

Most others who've tried it have found that it works well, and seem to like the results a lot. I'll let that speak for itself. Well, that and the low heat transfer characteristics of good-quality fuel hose compared to steel tubing! Seriously, though, it sounds like there's something else causing your hot-start issues. The fuel line mod isn't a magical cure-all; you still have to have the rest of the fuel system configured well and in good shape.

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

It worked on my car. Actually I had to do my own variation of this before I ever even found this board. Couldn't get my car to start in the summer after sitting out in the sun. Had a length of rubber fuel hose and it wasn't long enough to go around the valve cover. Ran it over the valve cover straight to the carb and just attached the rubber hose to the 2 inches of original metal fuel line sticking out of the carb. Has worked perfectly ever since.

Ok, fine. You want to call a spade a spade, let's do this then.
"How many people out there that own A100's, have you folks done this mod and what were your results?" Come on now, speak up!

Ok, more light, less heat.

Minor quibble: Heat does not rise, per se. Hot air tends to rise. Heat moves from areas of lower temperature to areas of higher temperature. Fluids tend to expand as they are heated, become less dense, and gravity starts a natural convection current, unless blocked or overridden by other forces (pumps, fans, wind, etc.). Convection heat transfer increases with the fluid flow rate.

Unfortunately, our engine bays were designed with little regard for air flow in driving or at rest.

A significant part of fuel heating issues involve radiation, not just convection. (Ironically, car radiators work primarily by convection, not radiation. Go figure.) Radiation heat transfer decreases with distance from the heat source. Shielding helps – think shiny metal.

Because there is less air moving while the car is parked, moving the fuel away from the hottest masses will have the most impact in hot start situations. Rerouting the fuel line away from the exhaust manifold and block is a good idea. Proper carburetor to manifold gaskets help with the conduction aspect.

BTW, I don’t have a dog in this fight. I made my own fuel line, routing around the valve cover with steel line and a short length of rubber. The original line was damaged, so I made one to my liking. I do not have vapor lock issues. Dan’s method makes sense for a lot of people. Frankly, the factory approach works OK when everything else in the system is up to spec. It’s when the cars get old, some of the systems are worn, damaged, modified, or asked to do more than they were designed to do that problems show up.

What gets hot on a Slant Six? I’m glad you asked! Click below:


SLANT SIX THERMAL TIME LAPSE

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"When you find a big kettle of crazy, it's best not to stir it." - Pointy-haired Boss

1964 Valiant V200, 225/Pushbutton 904
BBD, CAI, HEI, LBP, AC, AM/FM/USB, EIEIO

But with less heat, we wouldn't even need to be discussing this at all!
Yep…and an A100's gotta be one of the worst in that regard…an insulated, closed-top box with no airflow at all once the engine's shut down. Also, today's gasoline/gasohol is designed with little regard for its volatility at high temperature and atmospheric pressure (like when it's sitting in a hot engine bay fuel line or carburetor bowl) because virtually 100% of the on-road fleet is fuel-injected any more.

69a100, a carb heat shield's a very good idea. The factory installed them in the early '80s. And have you looked at installing a vapour-bleed fuel filter (Wix 33054 or NAPA Gold 3054, Purolator F20030)? In addition to the inlet and outlet nipples, it has a 3rd nipple which is a vapour return. It has a 0.060" orifice and takes a ¼" hose, which you must route safely back to the fuel tank (a hassle, but not impossible). This helps alleviate high fuel pressure that develops between the pump and carb after shutdown.

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

A100s are notorious for having overheating issues doe to the obstructions to air flow inherent in the placement of the engine.

69A100- be sure your belly pan is in place and in good condition. Also, an electric fan that can continue to run once the motor is shut off can help dissipate the heat that builds up in the doghouse when the motor is shut off.

I can't even get a answer to why A100s don't have a vent line at the tank, let alone how I can fab one. It's a PITA in the summer as I can't have more than a 1/2 tank of gas as it will dribble out of the filler after a drive. And don't even try to remove the cap as you will get showered with gas. [Yes, the cap is vented]
Reed- I don't have any type of overheating issues, cooling system is in outstanding condition, and my belly pan is fine.

Oof…that tank's gotta be vented! I don't have my truck FPCs here (they're still in Denver ) or I'd post pics

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

Good for you. But if you are still having hot start issues then the electric fan will help.

Nope, none, zip, zilch, nada, nothing! I assume FPC is the parts catalog? When sweptline.com had there's online, I studied it hard, it showed exactly what I have. The D-100s had a tank vent, but A-100 didn't, go fig there? I believe a couple years ago I put this topic here and came up empty.

Sorry, by "gotta be vented" I meant "needs to be vented", not "is vented and you're just not seeing it". What a weird design screwup if your tank isn't actually vented. If the cap is definitely of a vented design, have you checked to make sure the vent is free and clear?

I found your previous thread, but the image links no longer work. When that thread left off, you were going to try creating a tank vent. How did that go?

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

Yea, that's the one I was talkin about. I studied the situation and found that there is a vent that goes from the tank to filler neck which I assume is to burp the system when filling the tank. I thought of tapping into that for a vent a taking it higher than the fill hole. But, 1. there's not enough room to make that happen, and 2. trying to find a T-fitting or something of the like for doing #1 turns out to be a bigger problem or tracking down the parts to fab some/anything. Sooooooooo, when the weather turns to the hotter that is does here in Cali. I just leave the tank at 1/2 or less and deal with it. I probabaly drive about 300 miles a month with it so it's not that much of a PITA to deal with. My problem now is that it appears that my rear main seal is taking a dump as everytime I drive and park it, I get a oil puddle about the size of a quarter within 5 mins after parking and alot of oil drop spatters all over the back of the van. I have been stockpiling parts for a rebuild. I have everthing except the main & rod bearings as I'm holding out till I find what undersize I might need. I just need to get my brother to move out for his new job so that I can have room to yank the motor.