Need help combating Vapor lock... 65 Ply SF 383

I use nothing but non ethanol 91 or higher octane gas. My question is,
Does the premium non- Ethanol fuel help prevent vapor lock?
 
Here's what I would do....

First, I would check for fuel flow. Real simple, takes a soda bottle, screwdriver and a rubber hose. Undo the fuel line and attach the hose and stick the other end in the soda bottle. Unhook the coil wire and crank the engine over while watching the flow. It should fill the bottle real fast.

That tests your fuel pump and pump push rod length.

Next, from personal experience, the electric fans don't cut it. I'd use a plain old OEM fan with the HD fan clutch (I can't remember the part #) Would your car have a fan shroud? I'd also use a 160 degree thermostat. I know... I know... I get exactly how it works, I just have had better luck keeping the temps down when I start the cooling cycle a little earlier.

Next on the cooling side, does your car have ALL the assorted rubber "splash" shields in place? They serve a purpose of keeping the air channeled through the radiator at speed.

First though, I do the fuel flow... You aren't running that hot that you should be having problems.
 
Where can I get the carb insulator gasket for a Carter. I see them for Holley, Street Demon and others. Can I use an Edlebrock?

Mr. Gasket Carburetor Heat Dissipaters 97
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Here's what I would do....

First, I would check for fuel flow. Real simple, takes a soda bottle, screwdriver and a rubber hose. Undo the fuel line and attach the hose and stick the other end in the soda bottle. Unhook the coil wire and crank the engine over while watching the flow. It should fill the bottle real fast.

That tests your fuel pump and pump push rod length.

Next, from personal experience, the electric fans don't cut it. I'd use a plain old OEM fan with the HD fan clutch (I can't remember the part #) Would your car have a fan shroud? I'd also use a 160 degree thermostat. I know... I know... I get exactly how it works, I just have had better luck keeping the temps down when I start the cooling cycle a little earlier.

Next on the cooling side, does your car have ALL the assorted rubber "splash" shields in place? They serve a purpose of keeping the air channeled through the radiator at speed.

First though, I do the fuel flow... You aren't running that hot that you should be having problems.

I know I have good fuel flow, but I'll check it anyway. I think it's the electric fan. It just doesn't move enough air.

I don't have all the parts for the correct airflow. I only have the hood to radiator seal. I would need a shroud. My car did not. Come with it for it's year and the electric fan was already there. I do have the original mechanical fan, but no clutch. It's a straight bolt on.

I'm going to try a few things one at a time. First flush the motor and rad, just to see what I'm dealing with. Previous owner said he had heat/vapor issues and had the rad flushed and boiled. I have the receipt for the work. I know it was done, but looks like it's all anti-feeeze.. which I know is not good. Antifreeze is just that, glycol. It's not made to transfer heat...just keep stuff from freezing and remove snow on airplanes.

With that, I'll change the thermostat, and hoses. They look old, so won't hurt to swap them. Again, the bottom hose doesn't have any collapse spring in it, so who knows if it cavitating. I'll also swap the water pump, flush the motor and add new blend of 50/50 coolant.

From there, I'll move into the intake manifold and see how that helps.

I think between those two, I should be in better shape.

If you can find the part number of the fan clutch, that would be great.

Thanks for the advice as always.

I found the other day when I was cleaning my starter and driver's side of the block... This is the original motor from 1964. So I'm really keen on keeping it clean and running right

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Thanks. I didn't think to check eBay. I bought a this one and one made from gasket material on Amazon. I'll see which one I like better and send back the other.

So I have a few options to go through and hopefully one of them will fix the issue. I think the heat shield and the intake pan that blocks the heat tunnels will be a massive help. From there.... I'll work on the cooling system.
 
Using the spacer also improves bottom end torque response.
kinda like a mini-tunnel ram intake,LOL!!
 
Thanks. I didn't think to check eBay. I bought a this one and one made from gasket material on Amazon. I'll see which one I like better and send back the other.

So I have a few options to go through and hopefully one of them will fix the issue. I think the heat shield and the intake pan that blocks the heat tunnels will be a massive help. From there.... I'll work on the cooling system.

One other thing to consider: If the spacer you use is too thick, it will mess up the geometry of your choke linkage that runs from the well in the manifold to the lever that actuates the choke butterfly.
 
One other thing to consider: If the spacer you use is too thick, it will mess up the geometry of your choke linkage that runs from the well in the manifold to the lever that actuates the choke butterfly.


I was able to use the stock linage since I have an
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electric choke
 
Yes. That avoids the problem, but he sez he wants to keep his AFB. . .

I'm trying like hell to keep the originality of the car, but new technology competing with 55 year old technology is challenging to say the least. I'll keep playing around with different setups, but if all else fails... Yeah, the Eddie carb will be sitting on my manifold.

I know what I'm doing definitely won't hurt the car, it's only a dry and warm weather driver now. But at some point, if nothing else works, I'll have to consider modern options. It's kind of embarrassing to pull into a parking lot for a night show, and stall out. Hard start...stall...hard start...etc

The 1/4" spacer should be fine. I had the CoolCarb plate on it which was closer to 1/2" and like you said... totally screwed up the choke linkage.
 
I'm trying like hell to keep the originality of the car, but new technology competing with 55 year old technology is challenging to say the least. I'll keep playing around with different setups, but if all else fails... Yeah, the Eddie carb will be sitting on my manifold.

I know what I'm doing definitely won't hurt the car, it's only a dry and warm weather driver now. But at some point, if nothing else works, I'll have to consider modern options. It's kind of embarrassing to pull into a parking lot for a night show, and stall out. Hard start...stall...hard start...etc

The 1/4" spacer should be fine. I had the CoolCarb plate on it which was closer to 1/2" and like you said... totally screwed up the choke linkage.

Has the routing of the fuel line in the engine bay been altered at all?
 
No. It's stock. Which I'm guess is adding to the problem as I have an electric fan. It doesn't provide that blast of air you get with a mechanical fan. So my fuel line and filter, along with everything has little to no air flow around it when the fan is off, let alone when I'm in traffic/driving slow.
 
You can just sneak one of holley’s smallest inline electric pumps close to the tank. Mount it on rubber isolators. Believe it or not, my 85 3/4 ton dodge has a tiny electric pump down in the tank, on the end of the sending unit. And it also has a third nipple on the filter that goes to a 3/16 return line. You could probably disguise a return line pretty easily with the low mounted filter. I don’t think the return line is a must, but it will keep fuel circulating (cooler)
 
You can just sneak one of holley’s smallest inline electric pumps close to the tank. Mount it on rubber isolators. Believe it or not, my 85 3/4 ton dodge has a tiny electric pump down in the tank, on the end of the sending unit. And it also has a third nipple on the filter that goes to a 3/16 return line. You could probably disguise a return line pretty easily with the low mounted filter. I don’t think the return line is a must, but it will keep fuel circulating (cooler)

I found a video with a guy talking about this on his old 40's Pontiac. Seems like it would help a lot.

Even better from Uncle Tony's Garage... sounds like a Long Island guy... could be Jersey as well. We sound similar.

 
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I found a video with a guy talking about this on his old 40's Pontiac. Seems like it would help a lot.

Even better from Uncle Tony's Garage... sounds like a Long Island guy... could be Jersey as well. We sound similar.


I believe that you are on to something.
I re-read all of the posts and @Big_John pointed out checking fuel flow.
It appears that you haven’t checked that, when the engine is hot, or at all since your original post.
I would recommend you do a relatively simple test by taking some measurements with a temp gun, and installing a clear fuel filter as near to the carburetor as you can.
The test that I envision will get the engine and equipment under the hood HOT, watching the added fuel filter and scanning temps of the engine and equipment in the path of the fuel line.

I think the video that you found which installed the 3 teet fuel filter is on the right path, but what you find out when you investigate more will lead you to the problem. To solve it, you have several options, that may correct the issue, but I believe that the solution in the video is one that might bring the most benefit.
 
my '65 300 383-4 bone stock. 4 blade fan, no shroud, factory afb, runs on cheapie pump gas. daily driver runs perfect never overheats. i'm just a lucky duck.
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So I made some minor adjustments today and went out all day. Already seeing a difference.

First is the temp that I was running at. The electric fan was engaging too high, around 195. So I dialed it back to keep the temp at 180. Seems to hold well at 185.

I also swapped my larger dual snorkel for the original small unsilenced air filter cover. This created more room and airflow around the top of the engine.

Seems to have helped as I went all day driving with no loping or stalling.

I have the new 1/8" carb gasket from Edlebrock, I'll be installing that next week as well as the Fel-pro pan that blocks the heat tubes.

Also on the list is the high flow water pump, a high flow 180 thermostat and a motor flush out.

I'll hold there and see what the results are. Is like to keep the dual snorkel, just depends on how well all of these mods keeps the motor cool in traffic ... And in Long Island, traffic is like breathing... It's all day, everyday, everywhere to everything.
 
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