Need advice on how to correctly manage vapor lock

vapor lock is something i have fought for years and keep fighting. every few years it gets worse.
in the 80s-90s almost none existent. 2000s only on really hot days and crawling on trails. 2020's some sort of vapor lock on every trail. --- what's happening is the fuel blends are getting worse for carbureted engines.
i like you want to keep my carb, and not go the fuel injection route. i just don't find them reliable enough to trust 30 miles from no where all alone.

things i have done over the years to fight vapor lock---
1. wrap the fuel lines in some kind of heat reflective wrap- i used a product called lava tube.
2. route fuel lines away from any heat source. on mine i come out of the mechanical pump and go against the passenger inner fender--- then up near the heater box--- then over to the carb.
3. in stall a fuel cooler- (my cooler is more or less a metal tube with fins on it- i bought it from a guy in nevada- crude looking but the fuel comes out cooler)
4. use a heat insulator carb gasket.

for me in Colorado altitude and summers, doing the above eliminated vapor lock in city driving be it stop and go or normal Denver traffic. im still fighting some vapor lock on trails especially 11,000 feet and higher. ( my next step is going to be to add a return line to the fuel system)

also you mentioned your running some what hot in normal/traffic driving.
do you remember what temp your thermostat is ? iv found my scout holds about the setting thermostat temp in city traffic driving/ with A/C going. if your is constantly over the thermostat temp, things i would check would be--- air flow across the radiator and engine timing. at idle with a good fan and good shroud there should be enough air flow to hold/suck a single piece of copy paper up against the radiator and A/C condenser.
your engine was just rebuilt- maybe the timing is to low or to high. off in either direction will build excessive heat
my altitude i find about 10-13 degrees of timing is best for me. (my timing marks are getting very hard to read)

good luck in the fight keep updating- id like to know what works for you and if i can apply that to my fight also
 
Thanks for the reply and advice. I really appreciate it. I think part of my problem is I have a air bubble stuck somewhere in the cooling system. The block is not getting a chance to cool. Temps rise with no relief. I'm waiting on a no spill radiator funnel kit by Lisle to arrive so I can see if that will help purge the bubble out. While running from a cold start, if I take the radiator cap off it has non stop trickle of coolant flowing over the radiator neck. That's with it being cold, thermostat not activated yet. Hopefully this will work. I've put a little over 6 years building it, now I want to drive it.

Currently my timing is at 10 deg BTDC, idles in drive foot on brake 700 RPM'S with 15 in vacuum. It's happy there. Always starts, no backfiring, no dieseling or pings after turned off. It took me a little time to find its sweet spot, but it runs great. In the cooler months I did not notice the vaporlock or heating issues. Now that it is summer I have time to drive it and the hidden gremlins are showing up. That's a good idea on the fuel line from pump to carb. I need to get some more DEI Heat wrap and wrap that and my mini torque starter. Everything else is wrapped from exhaust routing past trani pan, tranni lines from trani to radiator, electric wiring in engine bay, and hard fuel line to soft hose before fuel pump. I did my best to control the header heat. Stay tuned I will keep you all updated.
 
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If the engine is tight and new, it is going to run hotter for a long time. Modern fuels suck, and depending on your station and fuel blends, it will happen unless you do a electric fuel pump.
 
Zaedster, thanks for the reply. I've only used Chevron gas for it. It's good to know it will run hotter for a while. Is it normal with radiator cap off after a cold start that coolant will trickle out over the radiator neck?

Different topic, will you be doing a part two video on the 1980 diesel Scout upgrades?
 
The only thing that will probably help your situation out is getting a pump like this:

https://share.google/LOvZvTxt8ApTfr9qA

And a nice quality low pressure fuel pressure regulator. As your engine breaks in, you’ll continue to have to tune it. Depending on how tight it is, it will run hot for a long, long time. You need to run it hard to get it to break in if you’re doing lots of easy drives on it.

It just depends on your cooling system, what do you mean by trickle? It should be plumbed into the bottom of the coolant reservoir and you shouldn’t hear anything. It should pull in coolant as it cools and sends it out as it expands. Unless you have an air bubble somewhere.

Yes, hopefully soon. I have lots of plans and dreams but not enough time to execute them in a timely fashion. Thanks for asking.
 
Thanks for the info on the fuel pump. I took the radiator cap off while it was running from a cold start. I wanted it to get above 180 deg so I could confirm the Robert Shaw thermostat was working. I was hoping to see flow of the coolant. What happened with the radiator cap off was a steady trickle of coolant overflowing over the radiator fill neck. I would have thought with it being cold the coolant should have no moment until the thermostat opened.
 
Thanks for your input. From reading through everyones forum posts and Zaedster's comments regarding my rebuilt engine being tight as it is, it is natural for it to be running hotter. With my lack of knowledge on these engines, I'm overthinking things. I had no problems in winter or spring. They showed up in the summer. I just need to keep driving it and break the engine in further. Right now I have 390 miles on it. I will probably pick up a temp gauge so I can moniter the coolant temps and wrap my fuel line from mech fuel pump to carb. If the fuel lines continues to vapor lock I will relocate it away from the heat source. I LOVE THIS FORUM!
 
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