This is not about a Model T but Ford related. I am working on a 1948 Lincoln V12. The car is running great and start up right away when it is cold.
When the car is hot the starting up is a problem.
Today weather was great and warm (32°C) and we went out for a 100km test drive on high way and city roads. Car was ok on the high way but went very hot on the city roads but no boiling.
Each time when we stopped and shut off the engine it was very hard to start after 5 to 20 min
After 20 min waiting, the car started right up. During the road I bought a quick start spray. With the spray I could make the car start up within the 5 to 20 min time.
Could the high engine room temperature be the reason of the start up problem ?
Do you have any ideas how I can find a solution for this problem?
Vapor lock? Try with something that cools the metal fuel pipe in the engine bay.. - putting clothespins on the pipe has helped some, maybe because they create more whirls in the air that flows by?
An accessory fuel pump that pushes fuel from the tank might also help?
Clothes pins on the pipe only helps if you use metal ones that dissipate heat. Those may help. You can also wrap twists of solid copper wire from electrical #12 or 10 house wiring around the pipe, leaving the ends sticking out to dissipate the heat. Many early cars with the carburetor centered between the valley or with the carb mounted directly above the exhaust manifold as they are on in-line engines start hard after sitting because the carb heat sinks from the mainifold or engine heat and the gas does not flow all the way to the orifice before the gas vaporizes. One of the differences in the old rebuild kits and the new ones is that the old ones had an asbestos core gasket that stopped most of the heat sink effect. New gaskets tend to just be heavy cardboard or some kind of synthetic that allows the heat to pass right through and heat sink the carb.
Carburetors are designed to operate with relatively cool gasoline entering the carburetor and being sent on to the engine at temperatures not to exceed engine operating temperatures. The incoming fuel cools the carb and keeps the fuel flowing. Even on a very hot day the fuel entering the carb is under 120 degrees F unless it is being heated by engine or exhaust heat prior to entering. That is 100 to 150 degrees cooler than that fuel will be after setting in the carburetor for less than 5 minutes with no flow in and out.
Make sure that the fuel line to the carb is correctly routed, away from the exhaust pipe and manifold, be sure that the fuel pump mounting gasket is the correct one and that the fuel pump is taking a full stroke.
I would mount a low pressure electric fuel pump aft of the mechanical pump with a separate switch. Turning that pump on 5 seconds before attempting to start the engine will assure that the carburetor has gas flowing into it. That gas will be hot, as the fuel has been setting in a steel line between the fuel pump and the carburetor. Replacing that line with a larger line may help. Also, adding a fuel strainer with an air bubble in the top may help. If you can find the old type glass bulb "sediment bulb" type of fuel strainer, mount it "upside down" with the bulb at the top, between the fuel pump and carb. It will act as an air pressure equalizer, thereby equalizing the pressure/no pressure strokes of the fuel pump and will supply a constant stream of fuel to the carb instead of a pulse from the fuel pump. At higher speeds the pulse has little effect. At starting speeds the check valve in the fuel pump may not close in time to hold fuel forward in the line, especially if there is fuel vapor in the line along with the fuel. Also the pump will not pump vapor so it may not be pumping fuel to the carburetor. Removing the line and watching fuel flow to see if it is pumping is not an accurate test. With no restriction from the float valve the vapor escapes and the fuel flows, giving an inaccurate impression that there is fuel flow to the carburetor from the fuel pump.
The glass bulb on the sediment bulb you have now added should never fill with fuel if you have it installed with the glass bulb up. There will be a variation in how much fuel is in the bottom of the bowl but it should never fill.
I could write more but a carburetor awaits now that I have had coffee.
As always, you are kind to take the time to share your knowledge.
A great Forum, indeed!
Bad power valve or coil?
Have you tried posting on the Fordbarn Early V8 forum?
Those guys are pretty helpful.
(Message edited by Ab4875 on June 05, 2015)
In a few minutes I learned a lot. I will surely try the electric pump and the upside down sediment bulb.
You are great in the job you do with the carburetors ( I saved every photo of the carburetors you posted on this forum in the past) and you are great in the advice you give.
There was another thread on Fordbarn but darn if I can find it now talking about gas getting sucked back out of the carburetor to the fuel tank. The link above should get you started figuring out how to fix.
On a Flathead V-8 you can also have problems with the coil shorting out when it gets hot (even thought your problem sounds more like vapor lock). I am looking at sending my coil off to Skip Haney in Florida for a rebuild search the Internet for more info on him). With a coil down in the engine heat (front of the motor) it's a pretty harsh environment.
here is the other string I was looking for;
Mark, that is a possibility but there is a check valve in the fuel pump that should keep that from happening. If there are no air leaks in the system, which would show up as fuel leaks under pressure, there is no way for air to get in the system except by the float in the carburetor falling enough to allow the air to pass through the seat. The fuel pump check valve should stop any fuel from moving back into the tank.
Verne, while it's possible the coil is faulty, since it will start with starting fluid, I am assuming it is a problem of getting fuel to the cylinders. It will be interesting to hear what solves it.
Those V-12 Lincolns were a PIA from the time they were new. I think a lot of them got repowered pretty early in life with GM and Lincoln V8's along with a lot of other engines that had better starting and running systems. I think they all ran hot.
48 was the last year of the V-12. Are you sure you have the correct carburetor for it?? A lot of those cars were worked on a lot in the day and many of the carbs were replaced with carbs from earlier Ford V-8s. That carb is too small for the V12 and will cause it to overheat as speed because the venturi are too small to supply the needed amount of air/fuel mixture to run at the correct ratio, causing the engine to run lean and over heat. IIRC (I don't have time to look it up right now) the late V12's used a Stromberg 06 (Marked LZ) that looks very similar to the Stromberg 97. a 97 will make them overheat at speed. The 06 will mount right on the same 3 studs that the 97 mounts on.
Also make sure that the vacuum port is not opening up somehow if you have it hooked up. Some of those have one port, some have two. The port being open will allow air to be pulled in below the throttle plate instead of drawing fuel through the venturi. The port runs the wipers and the brake booster. Check all the vacuum lines.
Stan, should this sediment bulb do the job??
By reading your message before I remembered I had something like it.
A 6V low pressure pump is in the trunk of the car but is not installed jet but will be soon.
I will keep you posted on the way we found a way to fix it.
(Message edited by adminchris on June 09, 2015)
I will try to make photos during the weekend and post them.
Andre: Does it crank normally when it won't start? (you didn't mention this but if it's so let us know. It's an entirely different problem).If it does crank OK pull the air filter and look down the carb throat while operating the gas linkage full throttle. If it's boiling off the fuel you won't see a squirt of fuel from the accelerator pump shooting into the carb throat. A sure sign of no fuel in the bowl. You may even see vapor rising out of the carb throat if it's boiling off as the fuel evaporates. If there's fuel in the carb vapor lock/boiling off isn't your problem. Fuel in the carb? it should run. Unless something else is wrong. Pull a plug or coil wire and check for spark. If no spark feel the coil body. Very hot? possible coil failing.
The engine crank very well. While cranking there is 5.5V over the battery. The Voltmeter connected between the - pole and the starter terminal (car is + grounded) give me a tension drop of 0.4V. Between the +pole and engine ground is 0.3V.
I think this is as good as it could be. There was a starter relay problem before but this is repaired.
I don't think it will be the ignition because as soon as I spray start fluid in the air filter the engine starts up.
Next week I will try to find some time to install the sediment bulb and the electric fuel pump.
Need to find my bed now, 1.05am here.
I have had a similar problem with several old cars over the years. They would vapor lock any time the temperatures were above freezing. In every case the final solution was achieved when I cleaned the rust out of the gas tank.
Fuel pumps cannot draw fuel from a partially clogged tank outlet very well. As temperature increases the fuel will boil easily. Pulling a vacuum on the fuel makes it boil at very low temperatures. This is magnified by a stopped engine as heat collects under the hood with no air movement. You can put clothes pins, aluminum foil, electric fuel pumps, you name it on there and it won't fix a rusty gas tank.
When I mentioned the cranking business I only meant does it crank slowly when hot. Never mind that now. You say when you add start fluid it runs so your problem definitely concerns vapor lock/ boiling off of the fuel. This USUALLY occurs in the engine compartment area. Does your car have one of those thermostatically controlled flappers on the exhaust manifold? (I forget what they were called). It was supposed to direct a bit of hot exhaust gasses under the carb when the eng. is cold. If you have one and it's stuck closed it will cause the carb to boil off the fuel. It should open fairly soon after starting & warming up. If it doesn't your problem will result. I'm not sure an electric pump is an answer especially if the present pump is working OK because I think your problem is occurring after the pump. Your emptying the carb. It's either leaking or boiling away.
A couple of more thoughts. I am assuming a V-12 has a fuel pump push rod like a V-8. On a V-8 you can have a bad combination where the push rod isn't getting a full stroke because it is too short (worn), or maybe it is a wrong fuel pump is not the right one for the car.
If you are buying a replacement fuel pump, I'd be sure I was getting a good one from a reputable rebuilder. Lots of people have remanufactured fuel pumps. At one time, a NOS pump may have been OK but after this many years you might have problems with corrosion or the rubber diaphragm may be hard (brittle). The Early Ford V-8 Club would be a good place to look for a rebuilt one. Lately, they have been running a column in each issue that deals with what parts are good, and which ones aren't.
I believe the modern fuels vaporize at a lower temp so this is not helping vapor lock any either.
Another thing I've seen is problems with the starter circuit. With a 6-volt system, it is 1/2 the volts and twice the amps of 12-volt. The same thing happens here as with any 6-volt system (even the Model T)...if you don't have the 6-volt cables and a good connection, it may give you problems. A starter takes a lot of amps. It could be you just don't have enough amps left over to file the coil.
The 8's had a tendency to wear that fuel pump cam lobe out shortening the stroke. (if that's what the 12 has). Measuring the rods movement would tell if it's shot and a new pump wouldn't help if that cam's worn. Besides that he's not complaining about lack of power due to poor fuel delivery when running. His fuel is disappearing from the carb when hot and not running the eng. at all.
You need a new coil and condenser. If it's a standard 6 volt coil and condenser or common with the V8 then it would be relatively easy to find in the US .
You might try pushing it to start when it's hot and won't start. Without the voltage drop from the starter a marginal coil would fire and the car should start . Your symptoms mimic those of friend's 1928 Chevrolet and a new coil and condenser solved the problem.
I don't think it is the coil or points or condenser. As I try to start it up hot and I spray a little start fluid in the air filter it just start right away.
No the coil isn't a standard 6 volt coil as on the V8. Distributor, coil, points (2sets) and condenser (2) are in one unit at the front of the engine. (See drawing)
Anyway, thanks to all of you for the ideas you give me. I will try them out one at a time so I can find what will fix the problem. I will start with the sediment bowl and the electric low pressure gas pump.
Here is a couple of places to check for parts:
Halamicek Auto Supply 626 St. Joseph Gonzales, TX 78629 830-672-3017 In business since 20's,no t parts,lots of later NORS parts, incl windshield glass.
Antique Auto Supply
1225 Colorado Ln
Arlington, Tx 76015 USA
Stacy has been collecting new obsolete parts for 50 years.
Very interesting info, great thread guys.
Stacy Brown sold his business and most of the parts. Not sure who bought all that stuff.
I have been following this thread and you may want to go on the Early Ford V8 site if you haven't already been there. It is a very helpful site like this T site and there is a Lincoln section:
I have a '35 V8 and some of the same guys I read in the V8 section are active in the Lincoln section.
Ken in Texas
The 5 to 20 minute no-start period would be the classic symptom of vapor lock.
As promise here a few photos of the car, the engine "room", the ignition and the carburetor fuel pump as it is now.
I wonder, with the photos, if someone can tell me if the carburetor is the right one. I didn't find any name on it just the model indication "Model 06H".
I wonder If I can use steel woven gas pipe to replace the old copper gas pipes while I am setting the up side down sediment bulb and the electric gas pump? or should I use new copper gas pipe?
(Message edited by adminchris on June 09, 2015)
That is a Stromberg carb, the O6H is the correct one for the V12.
I would remove the line from the fuel pump to the carb and replace it with a new one. I would use copper for heat dissipation. I'd run it up from the fuel pump and then forward at a level slightly above the carburetor fuel inlet with a slight bend down to the carburetor. I would install the upside down glass bulb filter in the line near the carburetor.
A rebuild of the carb or a replacement is also probably in order.
I have had luck by adding a quart of diesel to a tank of gas to help with vapor lock.
Here is an update on what I did till now on the 1948 V12 Lincoln. It took a while to get the parts for the rebuild of the carburetor here in Belgium.( They stays 3 weeks on the custom service in Brussels) Now rebuild is done, just need to put it back on the car and try it.
Thanks for all you good advice, I will keep you posted on the way the test drive went.
Andre -- I believe your sediment bulb is upside-down. The glass should be at the bottom, so sediment will fall down into it.
Reminds me of an old Readers Digest story.
A "little old lady" went to her auto mechanic when her car had a problem. Sometimes when she went to her local ice cream parlor that car would not start up for her to leave. If she bought vanilla ice cream there was no problem. However, if she bought butter-pecan ice cream her car would not start.
Now, most mechanics wold low off a woman with this sort of complaint, but this mechanic worked on this lady's cars for many years and knew her. So, he said "Let's go get some ice cream and see what happens."
When they go to the store and she bought vanilla ice cream the car started fine. When they repeated the experiment and bought butter-pecan it would not start.
Turned out her problem was vapor lock. When she bought vanilla it was already to go and she was back in her car in minutes. The butter-pecan was hand packed while you waited. That extra five minutes or so was enough for the engine heat to cause vapor lock.
Mike, ordinarily you would be right about the sediment bowl but what we are trying to deal with here is vapor lock. The sediment bowl is intended to work as an air/vapor chamber to regulate pressure and allow fuel to flow when there is vapor building in the lines to the carb.
If you take a look at most of the fuel pumps built after the 50's that have glass bowls on them the glass bowl is above the pump, as Andre has his installed here.
Andre, I think this will solve your problems but if it doesn't this is probably the final fix.
Obtain a good quality fuel pressure regulator and mount it as close to the carb as possible. Just prior to the regulator, install a T in the line with a return line running to the gas tank. Install another regulator in that line. Then install an electric fuel pump prior to the mechanical pump. Turning on the electric pump will purge the line to the carb of all vapor and force fuel into the carb (as it has probably boiled away from the heat of the carb while setting). The relief pressure of the return line must be just slightly above the pressure to the carb so that the needle and seat can shut off the fuel to the carb but still have flow to it, just not forcing it to overflow the fuel bowl.
Another option is to install a shut off -- either electric or hand operated in the return line -- that you can manually open to purge the flow line.
You can even just run a drop line down below the engine, open the valve, run the fuel pump until you get flow and close it. The carb should then fill with fuel.
Make sure the vent in bowl is open or it will not fill. There has to be somewhere for that vapor to go.
That is actually what I would do)
Good luck with the project, let us know how this all works. Remember that a fuel pump will not pump vapor, only liquid. The average mechanical fuel pump only produces 2 to 4 lbs of pressure maximum, the pressure has to be low enough that the float/needle/seat mechanism will stop the flow from the pump to the bowl. Gasoline vapor will build pressure rapidly to several times that pressure. For a quick demo of how that works, put 20 drops of gas in a small sealed can that you have squeezed to dent the sides in. Paint it black, set it in the sun and wait for the sides to pop back out. You have to be pretty strong to push the sides back in against the pressure of the vapor from that expansion. Better be pretty careful doing that demo.
Off to the shop. Carburetors await. Hayfield awaits.
and All for your advice.
I will keep you posted on how it will go.
It will take while, the owner is for a holiday in greece till the end of July and I will leave for Spain on the 4th of August till 16th.
Just get a new challenge: Four early(1907/09) Heinze Coils to rebuild.
Ok here I am back again with an update of the fixing.
Carburetor and upside down filter was installed on the engine yesterday. Starting up cold was easy, it started right up as soon as there was gas in the filter.
Gas lever in the filter was about 15mm in the glass during the warm up. As it was late we didn't do a test drive but leave it run for about 20min. Gas in the glass came never higher as the 15mm.
Test drive was planed this afternoon and surprise, before starting the car, we checked the gas level and it was still the same 15mm.
The car started right up without the choke.
During the test drive the car run great and each time we shut it down for icecream or a drink it started up easy. What we found to was the engine temperature stays normal. Outside temperature was 30°C this afternoon. Before the engine temperature was near to boiling.
During the rebuild I found the float level about 3mm lower as said in the manual. Was the engine running to lean and became hot for this reason or is it the total carburetor rebuild that cooled down the engine???
Now I need your advice again!!
I am willing to install an electric gas pump as suggested before. There for we bought an low pressure electric pump a low resistant filter and a check valve. The pump will only be used to prime the gas circuit with fresh gas just before starting the engine (cold or hot). During the run only the mechanical gas pump will be in service.
In the drawing I made you can see two check valves. One in the bypass over the electric gas pump and one on the electric pump circuit.
As the electric pump is working the valve 01 prevent the gas running back to the gas tank but I wonder if the second valve (02) is needed.
The bypass is there because I doubt the gas can run freely through the pump while it isn't running.
Does the Lincoln have a Positive ground electrical system ? If so, fuse the negative in your diagram.
You are right Bob
Vapor lock at 32F? Come on guys, be serious.
If the car is being driven you gotta assume there is fuel in the carb.
When you park and idle a second while you turn off the ignition you/I gotta assume there is fuel in the carb.
Now after 5 minutes it won't start? What happened to the fuel that was in the float bowl of the carb when you shut it off? A ghost suck it out?
My daily driver is a '51 Ford V8.
I've been driving and working on those cars since 1950 or 51. '32 through '53 flat head V8 Ford, Mercurys and V12 & V8 Lincolns.
I worked 9 or 10 years for a guy who had five V12 Lincolns. I drove a '48 Lincoln Continental convertible in the 4th of July parade in Piedmont (Oakland suburb) this year/last month.
That does not mean I know a damn thing about Lincolns or Ford products or anything MECHANICAL BUT THE POSTER'S PROBLEM IS NOT VAPOR LOCK!
The fuel pump should put out 3 lbs of pressure. If it does then an extra gasket needs to be put under the fuel pump stand to get the pressure down to 2 1/2. May need two extra gaskets.
The next thing that needs to be done is get a rebuilt distributor that has new points and the timing set on a distributor machine.
And a rebuilt coil that has been done by a reputable Ford/Lincoln coil rebuilder.
You can put new coils on those adapters that take a universal coil until you are broke and you will still have trouble starting the engine when it has just been run and warmed up to operating temp.
If his fuel line is jammed tight shut I'd like to ask how in hell he got to the place where it vapor locked?!!!
Maybe he needs to inflate his tires. Ya, that's it.
I have seen that same problem many, many times. Once this spring on a '35 Ford.
I found that letting the car roll down a slight hill and letting out the clutch in gear when up to walking speed it would start right off, but grinding away on the starter did no good.
A coil rebuilt by the guy in Florida and now it starts RIGHT UP after driving for a an hour or more after it sits for 5 minutes 1 minute, 10 minutes....whatever.
And we had put 3 new universal coils on before that.
We used coils with built in resistor and bypassed the Ford resister.
Ford products can be a pain in the rear end.
The temp was C, not F.-----hot!
oops. At that temp a Ford or Lincoln with the fuel pump way up there on top of the intake manifold can cause problems in hot weather during stop and go driving. Especially if it has dual exhausts.
The fuel pipe is on the left, the exhaust system is on the right.
When you add an exhaust pipe and muffler to the left side you risk vapor lock, but not when parked and the engine stopped.
I still say it won't make the carb dry up after you stop and shut the engine down.
It should still start then run out of fuel from vapor lock.
After I put a dual exhaust system on my '46 Ford V8 I had trouble with vapor lock when I was in heavy stop and go traffic on hot days.
On the early V* site they often mention that 70% of vapor lock problems are caused by the coil.
30° C is about 95°F
And the ignition system was taken care off with new points, capacitors, coils and spark plugs before we start to work with the carburetor and the gas pipes. The car was original fitted with two exhaust pipes.
Guys, I was amazed when a search came upon this thread. I have a 48 Lincoln V12 with the exact same problem. I have had a problem with two defective replacement fuel pumps now, and have a new production pump on the way. If the new pump does not resolve the problem, I know where to get fine advice. I have already adjusted the fuel line to the carb up, away from the head. Thanks, Bill,}
Andre, I don't think your car came from the factory with two exhaust pipes.
Bill, if your car had gas in the carb when you shut it off......why won't it start later?
I have electric fuel pumps on my flat head Ford pick up.
Sometimes when I shut it down I turn off the fuel pump.
The truck will still start just fine after a few minutes or even a few days later, but it will only run a few seconds until I turn the pump back on.