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doubledaddy
04-22-2015, 10:08 PM
My 50 land cruiser will vapor lock driving down the road. I can raise the hood while it is running and the gas is boiling in the filter at the carburator and it will boil for about 15 min after shut down. I have had it die while drive around 30 mph and it cuts in and out at highway speeds. I spray the fuel pump with starting fluid to cool it and the boiling stops almost at once but comes back in about 30 seconds. All this just idling in the drive way. I changed the fuel pump but it did not help. I have never had a car vapor lock this bad. I installed an electric pump at the rear and it hasn't stalled yet but the gas is still boiling in the filter. I bypassed the mechanical pump, just running on the electric and everything seems ok, no boiling, but the pressure is only 2 psi at idle, around 5 psi with the mechanical pump. Is this enough pressure. Any ideas why the fuel pump is getting this hot?

Studebaker1962
04-23-2015, 07:31 AM
I have a 1962 GT Hawk with similar vapor lock problem. I am running 92 octane ethanol free fuel which I believe has a much lower boiling point than the fuels from years ago. I am in the process of finishing a fuel line return from a NAPA return line filter immediately before the carburetor. It has 5/16 in and 5/16 out with a side nipple that is 1/4 also there is about a ~ .040Ē orifice in the side nipple. This return line goes back to a nipple I had welded to the steel portionof the fuel filler neck. Obviously pump the tank out, scribe a mark for the nipple location, take the filler neck out and go to a weld shop. I ran 1/4 steel brake line from the front to the rear in the same path as the fuel supply line. I used hose to complete at either end. Many internet searches state that this will solve the problem. I am using a mechanical fuel pump and replaced the stock steel line that ran very close to the exhaust manifold with flex that I ran in a direction that should be cooler, but that did not stop my vapor lock, so now running the return line. I also removed the heat riser valve which did not help, I am Florida so donít need cold start-up help.

I am very close to being done on my return line and will post with hopefully success.

Jim

doubledaddy
04-23-2015, 09:51 AM
That may well solve the problem. Allowing fuel to pass thru the pump faster should help cool it. In the past I have seen cars with aluminum fins attached to the fule pump and gas line trying to cool the pump with limited sucess. Mine does not have any metal lines around the motor, it;s all hoses. The car came from Minneapolis and it has an engine block heater and I am thinking it may have a high temp thermostat, can't tell. The temp guage does not work and I'm working on that. Have not checked the heat riser to se if it is stuck closed.

dickeedee
04-23-2015, 10:03 AM
I have a '64 Cruiser 289, and have had numerous issues concerning vapour lock.
Last year I blocked off the intake crossover, rerouted the fuel line, and insulated it, put spacers under the carb, and replaced the fuel pump.
I thought I had it beat, until I was in line at the Detroit bridge border in Aug., it started acting up again.(of all places to have that happen).It did it a couple of times after that., I always try to use High Test, w/o ethanol.
This year, I have added an electric fuel pump, and removed the heat riser..
If it continues, I am going to do what Jim did above.
If it still does it after that
, I'll try a road flare..

doofus
04-23-2015, 10:29 AM
Doubledaddy, wasnt there a heat shield kit for champ and commander 6's. keeps exhaust heat away from pump. fix temp guage and replace thermostat first. sounds like engine running to hot now. then see what happens. Luck Doofus

Studebaker1962
04-23-2015, 12:10 PM
Dickeedee,

Don't get crazy with the road flares. Only drive on roads without curbs, you can coast over on the grass, have a cooler with drinks and a few snack bars. Enjoy the "time out" to cool off. As I said I am so close to finishing my return line. Will report back to the forum.

Jim

dickeedee
04-23-2015, 12:20 PM
Dickeedee,

Don't get crazy with the road flares. Only drive on roads without curbs, you can coast over on the grass, have a cooler with drinks and a few snack bars. Enjoy the "time out" to cool off. As I said I am so close to finishing my return line. Will report back to the forum.

Jim
My luck, the thing will go up in flames and some over zealous Insurance investigator will pull up this conversation!
I'm anxious to see if that does the trick for you.
Was that restrictor orfice in the fuel filter?
If it was , do you remember the Napa #?

TWChamp
04-23-2015, 04:32 PM
I have some white plastic spit tubing, just like the common black plastic tuving used for a wiring harness. My Model A had bad fuel boiling problems when using the ethanol crap gas, and the Model A has gravity feed to the carb, and only a couple feet of steel line under the hood. The white plastic wrap helped a lot, and I would try that on the Studebaker. Between that and the electric fuel pump, I can't imagine the problem would still exist. I wonder if a person can still buy some pipe wrap like the asbestos we used to get to wrap exhaust manifolds and exhaust pipes? That would keep the heat down a lot, and you could also use it to wrap the fuel line.

Studebaker1962
04-23-2015, 04:37 PM
The NAPA filter is "NAPA Gold" 3054

Jim

Studebaker1962
04-23-2015, 04:40 PM
http://i.ebayimg.com/00/s/MTIwMFgxNjAw/z/E2cAAOSw7aBVH0iM/$_35.JPG

deco_droid
04-23-2015, 04:52 PM
Doubledaddy, I am in Texas as well (in fact, I think I met you once when I came by to look at some spare parts)... Anyway, just thought I would add that I have not had any problem with vapor lock on my Commander, and I am still using a mechanical fuel pump and running our only choice ethanol gas. The fuel lines are all where the factory put them originally as well. Just thought that may help you narrow down your problem.

studegary
04-23-2015, 05:12 PM
I would first question if your car has its fuel pump heat shield in place. Many of these were left off when the pump was replaced. You can either buy a new or used replacement or make one up, if needed. It may not entirely solve your problem, but it would be a good start.

doubledaddy
04-23-2015, 10:20 PM
I have tried most suggestions with no luck. Even with it running the filter looks like a coffee percolator. I have not yet tried a heat shield on the pump, there is one on the carb. I bypassed the mechanical pump and went straight to the carb. This solved the vapor lock but the electric pump is only holding 2 psi, it's a cheap inline pulse type and is not able to keep up. It runs fine at 65 mph but starts sputtering when I try to accelerate for more then about 5 seconds.

I can't see the pressure guage while moving so don't know what's happening to the pressure. Think tomorrow I'm going to run a temporary line inside so I can see the guage.

Can anyone suggest a good 6 volt electric fuel pump? I have looked at the Carter P4259, add says it will deliver over 70 gph with a max pressure of 7-8 psi.

Think the return line off the NAPA filter may be something to try also. I found several old car fourms that listed this as a fix.

Dick Steinkamp
04-23-2015, 10:52 PM
"Ethanol crap gas" is not contributing to vapor lock...

"The higher the volatility of the fuel, the more likely it is that vapor lock will occur. Historically, gasoline was a more volatile distillate than it is now and was more prone to vapor lock." (http://en.wikipedia.org/wiki/Vapor_lock)

and..

"Vapor lock is also less common in other motor sports, such as Formula One and IndyCar racing, due to the use of fuel injection and alcohol fuels (ethanol or methanol), which have a lower vapor pressure than gasoline." (http://en.wikipedia.org/wiki/Vapor_lock)

Cars vapor lock LESS today because of our Ethanol crap gas...not more. There are at least 2 posters here who run non ethanol gas and still experience what they feel is vapor lock. I have owned at least 30 vintage cars in the last 15 years all running e10 and no vapor lock in any of them, even on hot days at altitude.


Also, IMHO, "vapor lock" becomes the quick diagnosis for a variety of poor running, stalling, and hard starting conditions. It seems odd to me that the same car(s) experience what the owner feels is vapor lock, but others on the same day with similar (or identical) cars do not. Post #11 is a good example of this. Once the owner has diagnosed their problem as "vapor lock", the search ends for what is probably the real cause.

Common causes of symptoms similar to vapor lock include:
1. Sediment in the fuel tank that periodically blocks the pick up.
2. Collapsed soft lines that restrict or halt the flow (especially as they get warm and softer)
3. Plugged fuel filters or sediment bowls
4. Weak fuel pumps
5. Blocked carb float bowl vent
6. Incorrect carb float setting
7. Carb that needs rebuilding
8. Pin hole(s) in the fuel line, or insecure hose clamps.
9. Ignition problems (especially coil and/or condenser that fail as they warm up)
10. Blocked fuel tank vent

kurtruk
04-24-2015, 12:26 AM
" I have not yet tried a heat shield on the pump,"


It is a factory part. It is (was) there for a reason. SI sells them. Item# 187748

Morris Van Horne
04-24-2015, 01:58 AM
CASO= clothes pins on the fuel line. Worked for me in a pinch.

StudeRich
04-24-2015, 02:29 AM
The only hole in your Theory's Dick is that the Man SAW the Fuel Boiling in the Filter, that eliminates all of your suggestions. :(

Mine is, find out why the Engine overheats, forget about "Vapor Locking".

studebakerkid
04-24-2015, 05:16 AM
The 54 wagon vapor locked, my 61 T cab vapor locked both of them I put in a fuel return line and the problem ended. Now for some reason Pinkie and my 65 never have vapor locked but they are both Mc Kinnons. When I Mc Kinnioned the 54 I left the fuel return lines in it. The Toyota T Cab I put a fuel return line in it as Toyota 20R fuel pumps have all been super seeded and only one pump is available and it has a fuel return built into the pump.

I even wrapped copper wire around the steel fuel lines from the fuel pump on the T cab and adding the heat sinks may have helped.

t walgamuth
04-24-2015, 06:05 AM
In my 51 Caddy I installed an electric fuel pump right after the tank and wired it into the ignition switch (actually not supposed to be the best but worked fine for me). When getting ready to start it I'd just turn on the key and wait until the fuel pump stopped bumping and fired it up. Never a problem after that.

JoeHall
04-24-2015, 08:36 AM
All of the aforementioned are good ideas and, if collectively applied as a "kit" approach, will make vapor lock bearable during summer heat. Also, one of these (cut and tailored to fit) has been very helpful for me, especially in reducing "after boil", and hot re-starts: http://www.ebay.com/itm/Holley-108-70-Under-Carburetor-Heat-Shield-/310381690095?hash=item484430bcef&vxp=mtr

doofus
04-24-2015, 08:37 AM
DD, address the engine temp issue first then work from there. I have used those cheap solenoid type pumps for years with great success. do one thing at a time and check your results. Doofus

Dick Steinkamp
04-24-2015, 10:37 AM
The only hole in your Theory's Dick is that the Man SAW the Fuel Boiling in the Filter, that eliminates all of your suggestions. :(

Mine is, find out why the Engine overheats, forget about "Vapor Locking".

Is the engine overheating? I haven't heard that from the OP. If it is, that certainly should be addressed as a priority.

Gasoline "boils" at 225C (437F). (see 4.10.1 here (http://www.faqs.org/faqs/autos/gasoline-faq/part1/)). Is the fuel REALLY getting this hot? Have you tried a laser thermometer on the fuel pump, fuel lines, filter, carb, and to check the dash temp gauge? (those laser thermometers are as cheap as $12 at Harbor Freight (http://www.harborfreight.com/hand-tools/thermometers.html)).

When do the vapor lock symptoms start (not the perceived boiling, but the missing and stalling)? How soon after cold start? Where is the water temp gauge when this happens? What are the temps at the pump, filter, etc. when it first starts to happen.

The fact that the electric fuel pump seems to solve the problem but the "boiling" continues in the filter would lead me to believe that the "boiling" may be a red herring. Plus, you bypassed the mechanical pump with the electric, so it is not the mechanical pump making the fuel "boil". With the electric pump, where can the fuel be picking up the heat to cause it to boil?...is there a fuel line running along side the exhaust pipe, over the exhaust manifold, etc?

Has the car ALWAYS exhibited these symptoms? If not, what has changed?

Son O Lark
04-24-2015, 11:25 AM
OP spraying the carb with starting fluid to cool it scares the crap out of me; I would not do it.

TWChamp
04-24-2015, 02:18 PM
My Model A has vapor lock problems from boiling gas if the temp is over about 75* and I have the corn crap gas in it.
With the good gas I never had a vapor lock problem.
Also the corn gas makes my plastic gas containers bulge out from the vapor pressure. I don't have that happen when they have good gas in them.

I owned a Renault R12 GTL back in the 80's and it used an AC pulse diaphram pump mounted near the gas tank. Several times I had to go under the car on the side of the road to tap the pump to get it working. I went through a half dozen of these lousey pulse pumps before I finally sold the car. I would only buy a rotary pump, which has no rubber or plastic parts to be damaged by the crap gas. Precision and Holley are two excellent electric rotary pumps.

For a good fuel pump, you can buy a Precision rotary pump from O'Reilly's for only about $55, as I had to do when the crap gas ate up my new mechanical pump diaphram in Michigan last year. Last summer I bought 2 Holley rotary pumps at swap meets for only $5 each. These sell for a little over a hundred, and have way more volumn and pressure than needed, so they recommend a pressure regulator. To reduce the pressure and flow I prefer to drop the voltage, so the pump lasts longer and the pressure and volumn is reduced to the correct amount. I run a 4 ohm 50 watt aluminum finned resistor on my 12 volt Holley in my 6 volt Studebaker. This reduces the voltage to about 2.7 volts as I recall, which is perfect for my 1950 Champion.
43100

doubledaddy
04-24-2015, 03:39 PM
First off, the gas boiling in the clear filter at the carb is with the mechanical pump in line with or without the electric pump. When I ran straight from the electric pump to the carb the boiling is gone.

I know spraying starting fluid is a fire hazard, would never spray on a running engine. The mechanical pump will boil for 15 to 30 min after engine stops. Spraying at this point will stop the boiling for 15 to 30 seconds and it starts right back. This will contuine until the engine cools. I have had cars in the past that would vapor lock on hot days but never one that did while it was running.

I temporarly installed the fuel pressure guage so I can see it while driving. It sits just under 3 psi when idling and about 2 on the highway. Drops to just over 1 psi when I accelerate or go up a hill. I don't know what the pressure should be but i'm sure this is too low.

The car has other problems that I plan to tackle next. I haved ordered parts to rebuild the distributor and plugs. Last is the carb, I was told it had been rebuilt by a carb shop in Detroit before I bought it but who knows.

I don't think it is overheating but I will know for sure this evening. The dash guage is dead but I have a mechanical one I am going to install after the weather clears.

t walgamuth
04-24-2015, 09:21 PM
I use the mechanical pump and the electric diaphragm pump together.

kurtruk
04-24-2015, 11:25 PM
Do you think it does not need the factory heat shield? :confused:

t walgamuth
04-24-2015, 11:54 PM
No. (If you're talking to me).

kurtruk
04-25-2015, 12:41 AM
No. (If you're talking to me).

No, the Original Poster with the issue.

karterfred88
04-28-2015, 02:29 PM
Maybe it's not "boiling" but an air leak in the line which is aerating the fuel, making it look like it's boiling--maybe at the fuel pump to carb line fitting or diaphragm in pump letting the liquid go down as air gets pumped up. I'd replace the lines, or at least run a temporary fuel hose to the tank fitting, bypassing all the steel lines and fittings and see what happens. Remember your "sucking" fuel on the inlet sides of your pump(s). The fact you are only seeing 1-3 psi on an electric pump indicates a suction problem--possibly air mixed with the fuel. Even cheapo electric pumps seem to put out 7 psi. Test it by removing the inlet line and running a rubber line into a gas can. It should suck up the fuel without any effort and easily give you 5 psi while idling. Don't need to drive it.

doubledaddy
04-28-2015, 03:12 PM
Does not look like an air leak. It boils only after it gets hot. the boiling is at the filter at the carb and continues for 15 to 30 min after the engine is shut off. There are no metal lines from the line below the engine to the carb, all rubber hoses. Also by taking the mechanical pump out of the line or cooling the pump stops the boiling and the pressure starts at around 6 psi cold and drops as it heats up. I found the heat shield behind the spare tire and installed it. This helped a little but did not stop it. I have a 2 gallon lawn mower gas tank I am going to install as a gravity feed. This will eliminate everything in the fuel system but the carb. If this works I will work back to the tank one piece at a time.

t walgamuth
04-28-2015, 04:38 PM
Does not look like an air leak. It boils only after it gets hot. the boiling is at the filter at the carb and continues for 15 to 30 min after the engine is shut off. There are no metal lines from the line below the engine to the carb, all rubber hoses. Also by taking the mechanical pump out of the line or cooling the pump stops the boiling and the pressure starts at around 6 psi cold and drops as it heats up. I found the heat shield behind the spare tire and installed it. This helped a little but did not stop it. I have a 2 gallon lawn mower gas tank I am going to install as a gravity feed. This will eliminate everything in the fuel system but the carb. If this works I will work back to the tank one piece at a time.

YOur signature picture looks like the 51 two door commander my dad bought new while working at the factory. He said it would go 103 with the stock single exhaust and after adding a second exhaust it would go 106.;)

It was surf gray with concord blue wheels so grandpa could build him a special seat. It had the v8 with stick and od.

When I was about 8 or 9 mom was driving it into town from greene township on old 23. We stopped at a light and a fellow in a chevy pulled up in the left turn lane planning to pass mom on takeoff. Mom did not realize he was racing her and took off at here usual snappy pace. He was eating mom's dust and tried to pull behind and hooked his right front bumper in our left rear. Then he locked up his brakes and dragged both cars to a stop while his car slid sideways as it would be with the bumpers hooked.

Mom was pregnant with one of my younger sibs. I had my bunny in a box on the back floor as we were taking it to the 4-h fair. Mom cried a little but when the police man came he had nothing but nice words for her.

The chevy guy was properly embarrassed.;)

karterfred88
04-28-2015, 06:46 PM
can you post some pictures of the carb, fuel lines and pumps? Maybe they will trigger some insight not already given??

Dick Steinkamp
04-28-2015, 07:52 PM
can you post some pictures of the carb, fuel lines and pumps? Maybe they will trigger some insight not already given??

Also, if you can get a hold of one of those laser thermometers (a good one on sale now at Harbor Freight for $25.99) post some temps when the fuel is "boiling" at the pump, fuel filter, carb, etc....as well as the engine temp at various points.

doubledaddy
06-08-2015, 09:15 AM
I noticed several comments about replacing hose with metal pipe. Does rubber hose have a higher tendency to boil gas? I have about a foot of hose into the fuel pump and about 2 feet to the carb.

jg61hawk
06-10-2015, 07:04 PM
This month's Turning Wheels in Tech Tip says add Diesel Fuel to the tank.

brokencookie
06-11-2015, 10:38 AM
I run a testing laboratory at an oil refinery. Gasoline composition varies quite a bit from season to season ( Thank you EPA). During the summer months the gasoline formulation tends to have more of the "light ends" which lowers the initial boiling point. This is primarily from the addition of butane. Butane is cheap and boosts octane so refiners add as much as they can during the EPA defined season.
Gasoline is not like water. Water is a pure substance that always boils @ 212 F ( at standard temperature and pressure). Gasoline is a mixture and it boils off 1 component at a time. During the summer you will find that it starts to boil around ambient temperature and as low as 70 F. It continues to boil off the lighter components until they are gone. So if you distill gasoline it starts to boil at very low temperatures and continues to boil until the heaviest components boil at about 437 F.
Adding diesel to the tank will not affect the IBP ( initial boiling point). It only serves raise the final boiling point (FBP). Raising the FPB ends up leaving a residue which coats the surfaces and helps protect from rust, etc.
Pressuring your gas tank effectively raises the IBP so that your gas does not boil in the tank. The higher the pressure, the higher the IBP. If your tank is not pressurized then your only solution is to isolate and insulate.



Sorry to be so long winded. Hope this helps.

Bruce