40 Gas Problem:

I put a used fuel pump I had on tonight.Thought I would try this first.Had a very hard time getting 40 to crank.The bowl filled about half way up.I poured a little gas down the carb and it would run for a few seconds.I took the gas line loose going to the fuel pump on tank side with no site of fuel in the line.I blowed the line out all the way to tank.I finally started filling the gas line back to the tank and she fired up and ran OK.I thougt it was strange that there was no sign of fuel when line was taken loose at first.Sounds like I almost have a problem at tank.How can I get trash out of tank without removing it from car?Can I see inside tank if I remove sending unit?I will drive her a while to see if changing fuel pump makes a difference.
 
You need to put a pressure gauge in the line to see what the pressure is. Over 3 lbs cold is good, 4 lbs max. The push rod could be a few thousanths short. It is hard to pull the fuel from the tank when the line is empty. Bob Shewman gadgiteer@aol.com makes a good flex line with a check valve built in the pump end fitting.This holds the fuel in the pump makeing it start easier. You can see the bottom of the tank when the sender is removed. Remove the pipe plug in the bottom of the tank and drain the fuel into several containers. As one is filling pour the other back into the tank through a cloth.Do this several times and if you only have a small amount of dirt it may filter out. G.M.
 
I still have the same problem with a different pump.So,I can rule out the fuel pump as the problem.The car seems to only do this fuel problem on restart after it has been sitting about 30 minutes from a hot drive.It cranks up and I probably don't get maybe 100 yards before the out of gas problem starts.I actually think I have a vapor lock problem.my fuel line is not steel all the way back to tank.There are several sections of the fuel line that have hose in it.Why,I don't know unless the line was getting cracks in it and they cut and added hose.It is old hose so maybe thats my problem.Where Is the best place to get a new steel replacement line from pump to tank? Again,I am sorry about long post.It is difficult to explain what my car is doing. Russ
 
This sounds like the gas is boiling in the pump. You need to get a laser pointed thermometer and check the temperature on the firewall where the gas line is clamped, the fuel pump and the carb below the fuel line. If any of the places are in the area of 120 the gas is almost boiling and the problem is here. Let me know and I'll tell you how to fix it. It was 88 degrees down here today and after an hour or more driveing at the hottest part of the day mine ran perfect and started right up. G.M.
 
If you have had the feed line replaced with rubber hose these connections are most likely the source of your fuel pickup issue. Rubber hose doesnt like new fuels. Simply replace the entire fuel line tank to the pump with a new steel line. 1/4" line can be purchased at a good auto pars store like NAPA in a bulk roll. You will need to also purchase two fittings called "Ford Nuts" they are the special design fittings to fit the tank and fuel line. They are usually in the Edelman fitting selection. If you are unsure of these nuts just show the parts counter guy the sample off your old line.
 
My car has about four sections toward the back that has rubber hose installed in the gas line!Why would someone do this?Maybe to repair a hole or cracked place? Carpenter sells copper line with fittings.Would it be OK to install this type line? I am not sure if the gas line in my car is even routed the right way! Is there a diagram out there somewhere that shows the routing or should I start crawling under other 40's? Thanks,Russ
 
Russ, To be specific, Carpenter doesn't sell copper gas line. What he and others sell is the original copper plated steel fuel line, still being manufactured by the original supplier, Bundy. This is the product you need, no matter who you b uy it from.

I'm not sure if you can get a diagram from Carpenter, but I can tell you that another supplier, Roy Nacewicz, can supply you with the correct hold down clamps as well as the fuel line, and will be glad to describe the routing over the phone for you, and may also have a diagram for you.

Roy Nacewicz Enterprises www.fordbolts.com
Concourse correct fasteners
 
When you install the new line start behind the master cylinder and feed it in the frame towards the rear, up the hump and over the rear cross member. Most cross members are threaded on the top for a clip to hold the line on it's way to the tank outlet. If you have dual exhaust I ran my line up between the doubled frame up to the cross member to keep it away from the exhaust. As you put the front section in place keep it in the frame and come up over against where the fire wall bolts to the frame. Keep it close to the top frame flange away from the clutch pedal arm. The fuel hose clamped to the frame will help keep cool. The firewall gets over 125 degrees where the gas line clamps against the firewall. This heats the gas to near the boiling point. I spaced mine out 2 "s from the firewall and insulated it from the below the firewall over the flex hose and over the flex hose fitting at the pump. In temperatures over 80 check the pump temperature if it gets to 125 it is at the vapor lock point. When it gets to this point and the engine is shut down the gas pushes back to the tank and boils in the carb. Bubbles form in the pump and the fuel pressure drops close to zero. G.M.
 
I have a 40 Station wagon that was experiencing similar issues when I aquired it this fall. It started fine and then the performance deteriorated to the point of being undrivable.
This winter Ken CT rebuilt the carburetor, fuel pump and distributor. He also supplied me with a Ford coil so I could eliminate the remote firewall conversion coil. For good measure I replaced all the cooling hoses and got a pair of thermostats from GM.

It all came together yesterday afternoon (ambiant temperature 73 F.) I started her up, backed her out of the garage and let her idle to let the new coolant circulate and allow me to put my tools away. I drove away feeling good and it started again. A little stumble with no load which after a stop to pick up my daughter, a shut off, a restart and then a 2 mile drive resulting in deterioration to no power.
I barely made it home.
I went in the house to eat dinner and went back out to start her, no luck. Spark was good, no gas in the line. I blew out the line and poured in fuel to start her. after stumbling to life she seemed ok so I went for a ride. One block down the street and the lack of any power persisted.
So tonight I am going to do the laser temperature test.
One question though. Can the flexible line to the pump inlet look good and not leak and still be bad?
The saga continues!
 
rosso, Get one of Bob Shewmans flex hoses with the check valve built in the pump fitting. His flex hose will never have a problem as long as you own the car if it does Bob will fix it. Check the pump temperarure when you have a problem, if over 120 pour water slowly over the pump and get the temp down near 100 and see if it starts. I have solved the hot gas problem on my 39. It was over 88 here today and I did all I could to get the fuel hot but it stayed in the 112 range and stared right up after stopping for lunch. It's looking like when the fuel gets hot the engine runs lean and the coolant temperature runs hotter. With the fuel cooler today the coolant was 170 today after driving about 1 hour. When the fuel was near the boiling point the engine ran 180 when it was 2 or 3 degrees cooler outside or in the 85 range oppossed to 88 today. One warning, if the metal clamps around your radiator hoses up near the stats are to tight they will pull the hose ID down and restrict the flow and not run as cool as it should. One end of the metal band is inserted through the slot in the lower metal hose support and bent slightly to hold it in place.. The other end of the band is bent like a hook Un bend the bent end and it will come out, unhook the other end. I made two new bands for the ends near the thermostats about 3/8" longer than the tight ones. I used the wider strapping material and ground all 4 edges near the end to a tapper back about 1 1/4" so the ends were the width of the old bands and fit in the slots of the support. Bend the hook on one end and a slight offset on the other end so it enters the slot. Put it in place and bend the bent end slightly to lock it in. The hose has been compressed and heated by the hot water so the new clamp or strap will be a little loose. When it gets hot and a few pounds pressure in the hose it will streatch out a little against the band and maintain the 1 3/4" ID. When squeezed in by the old clamp up near the thermostat it doesn't give full water flow. G.M.
 
Hmmmm. now my head is spinning. I have to go home and look at the hoses and clamps. I am having trouble visualizing what you are explaining. At this point I have the thermostats placed in the hoses as demonstrated and the hoses clamped to the radiator with "correct style" clamps. What little driving and idling I did the engine temp seemes fine. Before I installed them the heater never worked in cold weather because the engine never got warm enough. Last night (mid 60's) the needle sat at "N" and the heater was putting out.
At this point I have to figure out the fuel problem. having rebuilt all components (carb,FP,Dist) it has to be narrowed down to underhood temperature or gas supply. The car was used very little before I bought it and going through repair notes from the prior owner I spotted some similiar complaints. I may I have some "coffee grinds" in the fuel tank. This "Agrigas" likes to loosen every thing up and as explained cannot take the heat.
 
rosso on some 39-40 upper hoses there is a metal support under the hoses. These are held on to the hose by 2 flat metal bands. If the front band is choking the hose closing the ID some when the thermostat opens part of it moves back towards the engine. If the metal band is tight and to close to the stat and choking the hose the ID of the hose being smaller in the area of the tight band will restrict the coolant flow. This may not be a problem in cool weather as coolant is still flowing but in hot weather you need the full flow. I didn't mean to confuse you but wanted you aware there could be a problem. Your hoses may not even have the support and bands. G.M.
 
GM,
Thanks for the information, I am going to keep a wary eye out for any hose issues that may occur once I get this fuel issue solved. Oh, My upper hoses do have supports.
Ken Ct,
I am happy with everything you did for me. The car has seen very little use in the last decade and I want all components up to speed. Now I know what is NOT the problem. So I continue to track down the perpetrator.

Update......took her for a short ride. She ran fine for about a half mile and then started acting up. I drove for another mile home to check temperatures.
Ambient temp 62 F
Engine temp.(heads) 178-180 F
Top hose temp. 150-155 F
Carb bowl, fuel line between carb and FP, fuel pump in and out line 105-107F.

I think I have crap in the tank. Any thoughts?
 
No problem with the fuel pump at 105. Watch this temp as it gets hotter outside. The only temperarure you need to take as far as coolant temp is on the center of the heads just below the hose. Hold the gun the same distance, same angle and hit the red dot on the same spot every time. Both heads should be within a few degrees of each other. Attached is a picture I found in my files of the bands on the hose. As you can see on this hose the band is right in the area of the stat. G.M.
 

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rossodino34 said:
I think I have crap in the tank. Any thoughts?
Click to expand...

I think you have crap in the tank. Your car is acting just like mine did when I started driving it after sitting for 31 years. The tank was so full of rust it would plug up a fuel filter in just a few weeks and sometimes the larger rust flakes would plug up the gas inlet tube in the tank. Finally got tired of fighting it and replaced the tank.

I used to not only carry spare filters to replace plugged ones but a piece of hose I could shove on the end of the metal fuel line coming into the engine compartment and blow the crap back out of it to get going again. Here's what my fuel filters looked like in a very short time. I thought eventually all of the rust would be cleared out of the tank and into these filters but it never happened.
100_2693small.jpg


You can quickly figure out if junk in your tank is your problem if you take along a piece of fuel hose long enough to shove on you gas line and blow through when you start having problems. You gotta blow pretty hard for several seconds to break lose the log jam then you'll feel the pressure release and hopefully hear the air bubbles in the tank through you filler neck with the cap off. If all of that happens and the engine runs fine again, then you know.
 
Old Henry,
I have to agree with you. The tank has a refurbished look to it so I figured it was ok. That may have been done decades ago and this car was driven very little. That said, I am foolish not to address it. I just hate going there. Gas and its tanks are not an arena I look forward to working in!
 
You can take a quick peek inside the tank by removing the gauge sender and looking into the tank with a flashlight to see what is in there. The bottom of my tank was clearly covered with rust flakes that were clearly visible.
 
40Ford Here's a few symptoms of a slight amount of air being pulled into the fuel pump. I had the flex hose off Monday morning and noticed the pressure gauge in the pump to carb line fluxuateing sometimes more than it should and a very small miss once in a while. I also thought I smelled a little gas a few times. Today when I went to lunch I lifted the hood to check the fuel pump temperature and saw a little gas drip from the pump inlet. I turned it and it was loose. When I installed the flex hose Monday I only tightened the fitting at the pump finger tight. I tightened it up and the fuel pressure is now steady and the very slight miss was gone. When there is a leak in an old flex hose sometimes you will see a slight wet spot on the hose as soon as it is shut down. It don't stay wet long before it drys. I think the same would show up with a leak any where in the fuel line. This type leak is usually very small and drys fast. Some times little mistakes help solve problems. G.M.
 
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