[JT68cs]

Just bought a 68 mustang with a 302 4v with an Edlebrock 1406 carb.
Is the fuel line routed correctly? It goes under and touches the bottom of the radiator hose. I can not find any stats that the fuel lines run this way.
After about 45 minutes of idle in 40 degree weather the car will start running ruff and then stall. Can start it back up at half throttle but mostly will not start again. I let it cool down and it will run just fine until it heats up again. Can see air bubbles in the glass fuel filter when running and can see bubbles bubble up after car stales out and is sitting.
I have put in non-ethenol fuel and it helped a little.
I have not checked the fuel pressure.
Do I have vapor lock because the fuel is getting too hot being under the radiator hose and touching the block?
I don't have the guts to drive it very far. I'm afraid it will die at a light and I'll be stuck.
Thanks for any insight on the matter.

 

[crjackson]

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[AndyEckel]

Congrats on your new Mustang! All in all, the engine compartment looks pretty darn clean.

In response to your post, I hope the following helps. Please bear in mind that I am not a classic Mustang expert, but I have stayed at a Holiday Inn express before. Your one picture is really helpful. Again, bear in mind, I am just trying to help. I am assuming you are not attempting a concourse level show car rotisserie restoration here. But looking for reliability and enjoyability. OK, here we go.
- - - -
I agree with your observation the fuel line routing, highlighted in pink, looks wonky IMHO. Again, I am not a classic Mustang expert, but I would not have routed it like that. Areas of my concern are highlighted in lime green.

In a general sense, since this is more of a "restomod", I would much prefer to route the fuel supply line from the gas tank to the engine compartment alongside the passenger frame rail. Risk is generally low, but consequences can be high for the fuel supply line being underneath the driver side seat. Why not bring the fuel line up alongside the pax side firewall, tuck your fuel filter somewhere appropriate, and connect it to the carb from the rear?

If you zoom in, the lime green arrows are pointing to places where the fuel line is already chaffing, has tool marks, and an air bubble. I can see why you may be experiencing vapor lock. And may likely experience a leak in the future.

PS: You need to take a look at your hose clamps, several of which appear to be waaaay too tight. And also some of your wires which are already chaffing too.

 

[Grimbrand]

This is what concourse routing looks like.

 

[JT68cs]

This is what concourse routing looks like.

View attachment 795341

Thank you, That is what I have seen also. I'm guessing they made a custom fuel line to kind of hide it better on mine. I think it is heating up the line way too much.

 

[JT68cs]

Congrats on your new Mustang! All in all, the engine compartment looks pretty darn clean.

In response to your post, I hope the following helps. Please bear in mind that I am not a classic Mustang expert, but I have stayed at a Holiday Inn express before. Your one picture is really helpful. Again, bear in mind, I am just trying to help. I am assuming you are not attempting a concourse level show car rotisserie restoration here. But looking for reliability and enjoyability. OK, here we go.
- - - -
I agree with your observation the fuel line routing, highlighted in pink, looks wonky IMHO. Again, I am not a classic Mustang expert, but I would not have routed it like that. Areas of my concern are highlighted in lime green.
View attachment 795330
In a general sense, since this is more of a "restomod", I would much prefer to route the fuel supply line from the gas tank to the engine compartment alongside the passenger frame rail. Risk is generally low, but consequences can be high for the fuel supply line being underneath the driver side seat. Why not bring the fuel line up alongside the pax side firewall, tuck your fuel filter somewhere appropriate, and connect it to the carb from the rear?

If you zoom in, the lime green arrows are pointing to places where the fuel line is already chaffing, has tool marks, and an air bubble. I can see why you may be experiencing vapor lock. And may likely experience a leak in the future.

PS: You need to take a look at your hose clamps, several of which appear to be waaaay too tight. And also some of your wires which are already chaffing too.

I'm betting they marked up the fuel line when they made it. I'm going to take it out and put a stock one on so it is further from the block, radiator hose, and doesn't touch anything. I'm hoping that will keep it much cooler. Will also take care of the wires. I went out and looked at the distributer wire and it was about a 1/2 from touching anything but the rubber part does not fit snug into the housing so I will change that out too. It looks to be an old original wire. Thanks for taking time to post.
Should the fuel filter have air in it when it is running? When first started fuel filter has no air and as it warms up more and more air shows up until it is half full.

 

[JT68cs]

Also I went to a hot rod hot shop and they told me I have an air leak in my fuel line and vapor lock does not occur unless there is air in the line. I have no fuel leaks so not sure how air is getting in the system if that is the case. I'll have to research that a bit more.

 

[Grimbrand]

Also I went to a hot rod hot shop and they told me I have an air leak in my fuel line and vapor lock does not occur unless there is air in the line. I have no fuel leaks so not sure how air is getting in the system if that is the case. I'll have to research that a bit more.

That shop is wrong about vapor lock not occurring without a leak. It does happen sometimes.

However, it is possible that on your fuel line under the car you COULD have leaks. There are a couple of places where corrosion does tend to happen, and the rubber hose connectors can get old and leak. You would surely smell it if it had an issue. If it's leaking past the pump, it would not put air in the line though, just be a fire hazard.

Having a filter before the pump, or a clogged-up fuel sender in the tank can also sometimes cause a problem.

Modern gas has a lot of alcohol in it, which aggravates the tendency for it to boil from too much engine heat. As a temporary but effective way to see what's going on, you can use a clear (PLASTIC, not the glass ones!) filter up by the carb. If your fuel is boiling in the line, you'll see bubbles in that filter, and when you turn off the engine after a run, the carb boiling will often force fuel out the vents. You can hear it, much like a tiny coffee percolator bubbling away.

 

[JT68cs]

That shop is wrong about vapor lock not occurring without a leak. It does happen sometimes.

However, it is possible that on your fuel line under the car you COULD have leaks. There are a couple of places where corrosion does tend to happen, and the rubber hose connectors can get old and leak. You would surely smell it if it had an issue. If it's leaking past the pump, it would not put air in the line though, just be a fire hazard.

Having a filter before the pump, or a clogged-up fuel sender in the tank can also sometimes cause a problem.

Modern gas has a lot of alcohol in it, which aggravates the tendency for it to boil from too much engine heat. As a temporary but effective way to see what's going on, you can use a clear (PLASTIC, not the glass ones!) filter up by the carb. If your fuel is boiling in the line, you'll see bubbles in that filter, and when you turn off the engine after a run, the carb boiling will often force fuel out the vents. You can hear it, much like a tiny coffee percolator bubbling away.

I will listen next time it does it. All lines,hoses, tank, and sender are new. I have followed the lines from the tank to the carb and all appears good. Line back by the tank seems a little close to exhaust so I will try to get it further away. I do get bubbling in the clear fuel filter I have there now. Car stales and as it cools little bubbles just keep bubbling into filter. Thanks for taking the time to respond.

 

[Tony 64]

The fuel line is running rather close to the head which if anything may cause your issue more that running under the thermostat but, have you checked to see what your timing is?
Too advanced timing will run the engine hotter. Windsors love timing. I used to run 22* initial and the motor run amazingly well, but ran hotter.
A carb spacer will also help a lot to stop fuel boiling.

 

[JT68cs]

The metal fuel line touches the thermostat housing, hose, manifold, and water pump bolt. I just don't understand why they ran it the way they did. I'll check the timing but the car is not running hot, it gets to normal temp. It already has a 1 inch spacer on carb too. Thanksj

 

[Siber Express]

BTW the air bubbles in the line are the gas getting hot enough to boil off and make vapor thus the reason for calling it Vapor Lock.
On my old 390 in my F100 used to get vapor locked until I did away with the Mechanical fuel pump and went electric since there was a lot of heat from the headers. I never even put the mechanical on my 4 bolt Cleveland in my 73 Cougar since the 850 Holley needed more gas than the stock pump could handle and it was vapor locking before the rebuild on it.

 

[JT68cs]

This is what concourse routing looks like.

View attachment 795341

Is this a 302 2v or 302 4v? Are they the same? I got another concour picture from a member, of a 302, and the fuel line runs to the right of the distributor. I have a 302 4v J code car. The Edelbrock fuel line is on the passenger side. Where this line runs I think it would work. I'll attach the other pic.

 

[Tony 64]

Your carburettor fuel inlet is on the other side (passenger), that is why your fuel line runs where it does.
Most factory engines have the fuel inlet on the drivers side like in the pic above as it is the most direct route to follow.
It doesn't matter if it has 2V or 4V heads.

 

[JT68cs]

Your carburettor fuel inlet is on the other side (passenger), that is why your fuel line runs where it does.
All factory engines have the fuel inlet on the drivers side like in the pic above as it is the most direct route to follow.
It doesn't matter if it has 2V or 4V heads.

One picture shows the line right of the distributor and the other shows the line to the left of distributor. Both are saying they are the correct routing. I need a line that will go to the left of the distributor.

 

[Tony 64]

One picture shows the line right of the distributor and the other shows the line to the left of distributor. Both are saying they are the correct routing. I need a line that will go to the left of the distributor.

Simple, buy that one then.

 

[07redstang]

Get rid of that fuel filter, it's a fire hazard. Do not worry about seeing bubbles in the filter, it is not an issue. I would re-route the line for the shortest distance between the pump and carb.

 

[il66pony]

Dont buy a stock pump to carb fuel line. It will not work with the 1406. Best to take it to a shop that can custom make a fuel line for you that will avoid the hot spots.

 

[JT68cs]

So with a lot of help I think I have a solution. Will it keep the car from stalling I don't know but will look much better and safer.
Going to buy a stock fuel line for a 289, Edelbrock hard line/filter, and an adapter. Will get rid of the glass filter and the line will no longer touch or be close to the engine. Will post an update if my problem goes away. Will be very similar to the picture. Thanks all for your help.

 

[Aggiesrok]

I was having a similar problem in the Texas heat. I ended up running a 3/8” line instead of the 5/16”.