I think my buick is vapor locking. I have never had a car to do it but I think this is what it is. Got a fresh build on the nailhead. it has about 1000 miles. It has been to Austin,dallas and a couple of other road trips with no problems. The car starts good[I checked timing}and runs good for about 10-15 miles. The engine is not overheating either. It just acts like it is running out of fuel. If I push it it seems like it is running on about 4 cylinders. Don't push it much past idle and it'll go. I did re-route my gas lines and changed them out ,thinking maybe I had one that was collasping. This time I put fuel injected line on it with a liner to make sure the line didn/t collaspse. It's about 100 degreesa and hot . What next? Change fuel pump? Maybe it's not putting out the pressure it should. Anybody had this problem? The car seems to retain alot of heat under the hood although everything is stock. What you think? Thanks in advance. I'm putting a new rebuilt fuel pump on tomorrow when it get here. Thanks in advance. TP
Hi terry, Have you cleaned out the gas tank? often a lump of something in the tank (rust, or a lump of coating flaked off if its been sealed) will get*****ed into the pickup tube and block the inlet, causing fuel starvation. it may not even show up as stuff in the fuel fliter. . if it has a sender, pull it out and see if you can see into the tank and check the end of the pickup tube. also check if there is a little screen filter in the carb fuel inlet, that could be blocked. Glad to hear you got the buick on the road. . it was just an old hulk when i last saw it! good luck with it, and Hi to the family!
TP, there's a lot of guys crying with similar symptoms on other forums, me included. I think it's the garbage they are selling for gasoline. Last weekend my bike ran like***** and I put hitest in, magically fixed it. My '24 DB would not stay running in 98 degree weather two weekends ago, ran fine when the air temp came down. Good luck finding it.
It can't be the gas if it runs ok for 10 to 15 miles before it*****s out. And it wouldn't run ok at just off idle
Rich, I understand what you are saying. I'm just not buying all the vaporlock theories either. The coil/condensor probably wouldn't run ok in TP's example either. These things can be hard to find sometimes.
NoboD,I am using premium gas in it so I don't think that is it. My buddy filled up with the same fuel and had no problem. lLowsuire,the tank was new so I don't think that should be a problem. Rich if the fuel pump doesn't fix it I am going to try the coil. I didn't think of that . It's aggervating as hell ever what it is. Thanks for the suggestions. I may get up early in the morning and see if it does it before it gets to 100. Thanks TP
Let us know what you find. These things have a habit of healing without knowing what caused it. I hate that!
noboD, I'' ll let you know. I have already ordered the fuel pump so I will try that first then I'll replace the coil. TP
I had a brand new fuel filter cause those symptoms. The car would run ok for a few miles, and then die out. If I sat for a few minutes, it would run again for a short time. I switched to another filter, and the problem disappeared . There was no visible dirt on the filter, and I think the filter element was simply too fine for the application. Also, an ignition condensor can cause odd problems. I had a bad condensor in my '55 Olds that would allow the engine to idle, but when I tried to accelerate, the engine would backfire and die. My experience with condensors was that even new ones might be defective.
Tonight on the way to a family picnic with the five kids and wife piled on the 50 Merc, I too experienced "vapor lock!" The flathead V8 was running just fine until I got into town slowed down to about 30 mph, then the engine just killed. I coasted over to the side of the street and tried to start it again. It would turn over but wouldn't stay running. Eventually after my wife and most of the kids got a ride home from a friend and while waiting for a tow, I tried to start it while in gear, and it popped and I was able to drive it home. A buddy of mine suggested it was vapor lock and said that a quick fix was to move the hard fuel line away from the engine where it could cause it to get overheated. I plan to check the fuel filter and carburetor tomorrow to see if there is any rust or***** floating around in the fuel line, which I have been told could be an indication of a rusty gas tank.
Gasoline now days vaporizes much easier than it did even a couple years ago. Since most cars have EFI, and high pressure pumps, the oil companies are not really concerned with vapor lock any more. In cars that I have been driving for 20 years or more, I am experiencing vapor lock, where in the past it wasn't a problem. Moving lines away from exhaust heat is one solution, but not always possible. Another solution is to run a pump with a return line, this circulates the fuel back to the tank helping to keep it cool. A third fix is an electric booster pump at the rear, when it starts vapor locking, you can turn on the electric pump, pressurizing the line, raising the vapor point. If there is no pump with a return line made for your engine, you can still run one, by Teeing into the line between the pump and the carb, and using a restrictor fitting to control the fuel flow in the return line. Solder the hole in the fitting on the return line shut, and drill from .060 to .090 depending on your fuel flow. This will supply plenty of fuel to the carb, but still have enough fuel flow to keep it from vapor locking. Weatherhead also has ball check valves available in 1/4", 5/16" or 3/8" that are adjustable from 3 to 10 psi, PN 63x4, 63x5, or 63x6.
I drove my 49 F-1 powered by a 322 Buick Nailhead back in 1978 in hot weather. I was also flat towing a 31 Vicky. I could not get past the vapor lock problem until I put about a dozen clothes pins on the fuel line from the pump to the carb. That fixed the problem and got me across country. I would try it just to see if that cures the problem.
Damnit! I have tried most of what everyone has suggested. New coil, new fuel pump,changed gas line to fuel injection line with a liner in case it was collasping. Tried again tonight and same thing at the exact same spot[about 10 miles from house]. The car has an ignitor ignition from pertronix. This may be possible breaking down. In the morning I will pull the dizzy and change back to points. Can a ballast resitor go bad and cause this type of problem? I also changed gas filter and moved lines. It just started doing this overnight. I'm puzzled. Any more ideas? I think I will mount an electric fuel pump inline and try that. TP
When I was living in Phoenix my Impala did something very similar the first summer I was there, I would drive about half way to work and then it would just lose power and get weaker and weaker then stall. After a few mins I could start and drive it for a little bit and it would do it all over again. I had a stock fuel pump on the block, so I got a electric pump and mounted it close to the tank and it never did it again. I didnt have a fuel pressure guage on it so I dont know what it was at , but my carb never overflowed and it ran fine for the next 3 years I had it there.
I am thinking that I may need to put one of those hard rubber spacers under my carb. The car retains alot of heat under the hood. Tomorrow I will mount an electric fuel pump inline.
He beat me to the comment. Have you replaced the cap lately? I had a lot of problems a few years ago on my 51 Merc because the "vented" cap didn't vent. The next time it acts up try loosening the cap and see what happens. I would go along with the trash in the tank theory too if it has been sitting for a while. A ballast resistor is usually good or bad with no in between. They usually either work like they should or they burn out and don't work at all. One thing that I do on all of my older cars is to put an inline filter between the tank and the fuel pump. It will catch most of the trash before it gets to the pump.
I had a similar problem with my 54 a few years ago. It would get to the same distance from my house each time, and all but stall. It turned out that something was intermittently plugging the main jet. I could still keep it idling because the accelerator jet was still working. So thats one thing to consider. The other thing is like was mentioned; the condenser, but I honestly don't know if a bad one would give you the 10 minutes of good driving. Is the fuel pump electric? And if so is it's psi on the high end for your car? I've heard that the extra pressure resolves the vapor locking problem. Good luck!
Keep the fuel flowing. Slow moving fuel will boil easily. while inching it's way forward, fuel will be picking up heat all the while. A long time ago I bought one of those typical in-line-can fuel filters with a small extra outlet on the can. It has a metered orifice to allow a small amount of fuel to be returned to the tank with another line. That small but constant movement of the fuel will keep it from sitting still and collecting heat. No more boiling fuel. The closer to the carb you can mount the filter with the bypass fitting, the less chance there can be of fuel getting hot and boiling.
This is just like the one I used from a 1977 Pacer. Many Jeep used that same setup. I just ran a new return line to the tank. The fuel recirculated just enough to keep the moving fuel inside the line to stay cool enough not to boil any more.
I had a similar problem but it only happened once and it was because of the choke. I had a carb that was in desperate need of a rebuild, the car would run for a while but then the choke would close on it and choke out the motor which sounds similar to what happens to you.
When I pulled the fuel line last night when the car stalled it had pressure on it. It could be something blocking the main jet. Do I pull the carb and blow cleaner back through it? I have a new vented cap. Does anyone think I need the phenolic spacer[Hard plastic}?keep the experiences coming. Something will work. I guess I need to just step back and think.Thanks everyone! TP
TP: I had similar problems with my 53 Merc flathead, but found that the engine does build up heat and that Merc ( in their infinitesimal wisdom) put the damn fuel pump on the intake manifold on that engine. I tried everything and found that it turned out to be the Octane of the gas. I was running 85 and 86 octane and it vaoporized really easy. When I put 87 octane in it, the vapor lock disappeared. Aside from that possibility, you have covered most, if not all of what I would do. The vent cap thing was another I have experienced, but you covered that. I would try two things, boil out carb and put some new gas in after that, with perhaps some gas treatment. You may have a clog that just happened from rust, etc. in the tank. Good luck.
Did the same thing to my 65 Ranchero 200-6 two weeks ago fixed the f^^ker. Once the temps here in phoenix got in the 90s I started having fits. Tried some spacers for carb ,change/rerouted fuel lines no joy. Got one of those vapor return fuel filters mounted it close to carb and ran a return line to the filler neck on the tank. Presto !! 110-112 + days and no more problems.
I put a new cap and rotor on this morning. A new vented gas cap, filter with a vent to the tank. It's creeping up to 100 so I think I'll go for a spin. Maybe this will fix it. I don't want to change everything at once. I want to figure out what the problem is .
Well seems like the filter with a return has done the trick. I just got back from a 40 mile hard drive with no problems. I'm kind of keeping my fingers crossed. I drove it 40 miles at 80-85 in 100 degree heat. No hiccups. Thanks to all that gave advice. I want to put it on the road for about 100 miles and see if it holds up.
Hi there I just posted a similar question, if you have a mechanical pump on your nailhead you may need to install a electric one.
There is always a first time and with the***** they sell and call gasoline it may be sooner than later. Hope you are not out in the sticks and your cell phone is dead!
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