Cadillac & LaSalle Club Discussion Forum

Cadillac & LaSalle Club Forums => Technical / Authenticity => Topic started by: VooDoo on March 12, 2023, 12:56:55 AM

Title: Dies while idling and losing fuel from the fuel bowl
Post by: VooDoo on March 12, 2023, 12:56:55 AM
So I'm in the process of trying to get my 1937 75 series convertible all dialed in so that I have no worries hopping in and driving it long distance. That's why I have a multitude of questions out there today. The furthest I've driven the car is about a 30 minute drive one ways. One thing I noticed, but after leaving the car idling for an extended period of time may be 15 minutes or so after the drive, the fuel bowl, loses fuel, and the bowl shows air bubbles coming in. The car starts to sputter and even if I try and give it a little gas it dies. I found this out today I was trying to leave the car running for an extended period of time because I was having an overheating issue that I was trying to diagnose as well. Any ideas what it could be? When I'm driving it, it seems to drive fine never losing any power or anything like that but again I haven't driven it for longer than about 30 minutes .  As you can kind of make out in the picture, the fuel bowl is not full and air bubbles are coming  up.
Title: Re: Dies while idling and losing fuel from the fuel bowl
Post by: James Landi on March 12, 2023, 07:28:02 AM
Sounds as if the increase in engine rpms above idle creates enough pump strokes and vacuum from the fuel pump to over come what is likely a tiny pin hole or leak in the fuel line outside of the tank, or a fuel line pin hole in the steel tank fuel pick up,or an air leak in one of the fuel connection fittings on the pick-up side of the fuel pump, or even a small hole or tear in the fuel pump diaphragm, or perhaps a leaky gasket on the fuel bowl. Tracking down and finding the air leak will require a good deal of patience;however, I suggect that you start with what YOU may have done with the fuel system prior to experiencing this issue.  Perhaps you had fittings off, or the fuelbowl removed or you moved a fuel line under the car, or you dropped the fuel tank to make a repair. There are ways to test the fuel pump by supplying the pump with an alternate fuel source, but this involves safely managing gasoline, temporary flexible fuel hoses, hose clamps, etc. Be extra cautious if you feel confident in doing this work and have a fire extinguisher handy.   hope this helps, James 
Title: Re: Dies while idling and losing fuel from the fuel bowl
Post by: VooDoo on March 12, 2023, 10:59:50 AM
Quote from: James Landi on March 12, 2023, 07:28:02 AMSounds as if the increase in engine rpms above idle creates enough pump strokes and vacuum from the fuel pump to over come what is likely a tiny pin hole or leak in the fuel line outside of the tank, or a fuel line pin hole in the steel tank fuel pick up,or an air leak in one of the fuel connection fittings on the pick-up side of the fuel pump, or even a small hole or tear in the fuel pump diaphragm, or perhaps a leaky gasket on the fuel bowl. Tracking down and finding the air leak will require a good deal of patience;however, I suggect that you start with what YOU may have done with the fuel system prior to experiencing this issue.  Perhaps you had fittings off, or the fuelbowl removed or you moved a fuel line under the car, or you dropped the fuel tank to make a repair. There are ways to test the fuel pump by supplying the pump with an alternate fuel source, but this involves safely managing gasoline, temporary flexible fuel hoses, hose clamps, etc. Be extra cautious if you feel confident in doing this work and have a fire extinguisher handy.   hope this helps, James 
I haven't actually done anything to the fuel system since I've had it. So that's gonna be a tough one
Title: Re: Dies while idling and losing fuel from the fuel bowl
Post by: signart on March 12, 2023, 12:55:40 PM
Was the car beginning to overheat when the fuel problem occurred?
Title: Re: Dies while idling and losing fuel from the fuel bowl
Post by: VooDoo on March 12, 2023, 01:02:05 PM
Quote from: signart on March 12, 2023, 12:55:40 PMWas the car beginning to overheat when the fuel problem occurred?
It got slightly above normal. Please see attached picture of temperature reading. I do know now that it was about a gallon of antifreeze low because of one of the other issues I was having with fluid coming out of the overflow. Hopefully I saw that now by adding a small little rubber gasket to make sure the plunger is seated properly. You can see my other thread.
Title: Re: Dies while idling and losing fuel from the fuel bowl
Post by: signart on March 12, 2023, 03:30:37 PM
Gauge temp looks ok. Not saying this is what happened here, but those cars are known to vapor lock when running hot or in hot weather conditions, which usually results in stalling, but will not immediately restart. Do well to research this for future reference.
Make sure you are not running coolant/antifreeze that is undiluted, no more than 50/50. Straight water will have a lower boiling point undiluted.
Good luck, I'm sure you will find plenty of help from experts on the Cadillac of your era.

As always, show a picture of your car when you get a chance, would love to see it.
Title: Re: Dies while idling and losing fuel from the fuel bowl
Post by: VooDoo on March 12, 2023, 04:19:37 PM
Quote from: signart on March 12, 2023, 03:30:37 PMGauge temp looks ok. Not saying this is what happened here, but those cars are known to vapor lock when running hot or in hot weather conditions, which usually results in stalling, but will not immediately restart. Do well to research this for future reference.
Make sure you are not running coolant/antifreeze that is undiluted, no more than 50/50. Straight water will have a lower boiling point undiluted.
Good luck, I'm sure you will find plenty of help from experts on the Cadillac of your era.

As always, show a picture of your car when you get a chance, would love to see it.
I've read that the antifreeze actually has a higher boiling point than water so I was under the impression that antifreeze would be better than filling it up with water?

And you are correct. It will not restart until it's cooled down.

Here's a link to my Instagram account where you can check out the car

https://instagram.com/voodoocaddy?igshid=YmMyMTA2M2Y=




Title: Re: Dies while idling and losing fuel from the fuel bowl
Post by: V63 on March 12, 2023, 04:46:20 PM
Water actually cools better. If you are using alcohol blended fuel that adds SIGNIFICANTLY to the problems. It hardens rubber parts (read : mechanical fuel pump). The original exhaust heated heated carburetor system, once great for Detroit freeeze boils off the fuel the other times.
Title: Re: Dies while idling and losing fuel from the fuel bowl
Post by: VooDoo on March 12, 2023, 04:49:18 PM
Quote from: V63 on March 12, 2023, 04:46:20 PMWater actually cools better. If you are using alcohol blended fuel that adds SIGNIFICANTLY to the problems. It hardens rubber parts (read : mechanical fuel pump). The original exhaust heated heated carburetor system, once great for Detroit freeeze boils off the fuel the other times.
So, even though the boiling point is lower with water, it actually cools better and wouldn't cause an overheating issue even with the lower boiling point if I'm understanding that correctly? I do currently run a 50-50 mix.
Title: Re: Dies while idling and losing fuel from the fuel bowl
Post by: signart on March 12, 2023, 06:27:58 PM
I think you may be addressing two different problems. An overheated engine doesn't guarantee  that it will result in an overheated fuel problem. As noted ethanol fuel can overheat and evaporate and cause a vapor lock which starves the engine, especially at idle. Again research vapor lock as to the causes and potential remedies, but also take the advice given concerning cracks, pin holes, fittings etc.

Great looking automobile, by the way. You can't hide in that baby!
Title: Re: Dies while idling and losing fuel from the fuel bowl
Post by: V63 on March 12, 2023, 11:09:38 PM
Water has the best cooling quality but any engine would be overheating once it boils. So 'coolant' helps by raising the boiling point but at the same time it reduces cooling efficiency. Also water has corrosive issues. So YES! Best keep antifreeze at a 50/50 blend. Also verify system is pressurizing.
Title: Re: Dies while idling and losing fuel from the fuel bowl
Post by: Jeff Rosansky CLC #28373 on March 12, 2023, 11:21:36 PM
A couple of things. I run a little Marvel's in the fuel. It supposedly raises the boiling point of the fuel.
A comment above mentions a pinhole in the fuel line. Pinholes won't really show up until they are really bad. I had that issue with our 55  what I did was undo the line at the tank and plug it. Then I put some mineral spirits in the line to fill it up. Then I blew pressurized air in the engine end. After a couple of minutes, there were a couple spots on the fuel line, especially under the clips.
Just a couple of thoughts.
Good luck.
Jeff R
Title: Re: Dies while idling and losing fuel from the fuel bowl
Post by: James Landi on March 13, 2023, 07:58:23 AM
"A comment above mentions a pinhole in the fuel line. Pinholes won't really show up until they are really bad. I had that issue with our 55  what I did was undo the line at the tank and plug it. Then I put some mineral spirits in the line to fill it up. Then I blew pressurized air in the engine end. After a couple of minutes, there were a couple spots on the fuel line, especially under the clips."

As I mentioned above and Jeff puts an additional emphasis upon, these tiny pin holes will NOT drip because there's sufficient vacuum from the fuel pump, the hole is tiny, and, as he states above, the likely spot is under a retaining clamp.  Jeff's approach, putting pressure AFTER the fuel pump on back to the tank input has efficiency, thus providing sufficient pressure to reveal any leak. Regarding the "hard starting" when hot--- I,too, subscribe to Jeff's fuel mix with Marvel oil.(I use a pint whenever I get gas)  It works "wonders" for me, and over time, I am not anxious about a "hot start/hard start" scenario.  Hope this helps, James
Title: Re: Dies while idling and losing fuel from the fuel bowl
Post by: skinny_tom on March 13, 2023, 01:29:47 PM
This sounds exactly like what was happening to my 65 when it was hot. The fuel is boiling in the lines from radiant heat when you're idling because there is insufficient airflow to keep the fuel lines cool. Newer fuels boil at a lower temperature than older fuels. (The Marvel Oil idea is a new on to me-- interesting) In my case it was that the PO had put the wrong fuel pump in the car and it couldn't move the volume necessary to prevent boiling. Just like in your case, I would watch the level of the fuel in the filter drop and eventually the engine would stall. Let it cool down (or throw some ice on it) and it ran great.

My solution was to install the correct pump. With the fuel return line to the tank, it is able to constantly circulate fuel and prevent it from boiling. Without a fuel return line, I would be looking to insulate or protect the fuel line from radiant heat (from the engine) since at idle your car will be moving very little fuel through the lines.
Title: Re: Dies while idling and losing fuel from the fuel bowl
Post by: Chopper1942 on March 13, 2023, 03:21:13 PM
Make sure that none of the steel lines are close to the exhaust system.  If any are, fabricate a metal heat shield (heavy aluminum foil, light aluminum or steel plate, or go to a junk yard and get a heat shield blanket off a late model car), and mount it between the exhaust and the fuel line.

Replace all your old rubber fuel lines. 

If you havn't replace the rubber fuel hoses and want to check them and the steel lines for pin holes,  connect a vacuum guage to the hose/line at the fuel tank and start the engine. Should be 15-18 in.Hg. If not, either pin holes or a weak fuel pummp. Remove the fuel inlet hose from the fuel pump and check the pump vacuum. Again, should be 15-18 in.Hg.  If not, your fuel pump is weak and needs replaced. If your fuel pump has a return line, the pump isn't moving the fuel through the system fast enough to keep it cool. Now, reconnect the inlet hose and remove the return line hose.  Connect a hose to the return line outlet and place the hose in a qt jar.  Have someone start the engine and see how much fuel is returning. It should fill a qt jar is around 30 seconds.  If it is barely returning fuel, the fuel can overheat in the lines and vaporize.  Needs a new pump.

Hope this helps.  Good Luck!
Title: Re: Dies while idling and losing fuel from the fuel bowl
Post by: V63 on March 14, 2023, 05:09:28 AM
I have made it a policy to block off the exhaust heating of the intake manifold. It does help with alcohol blended fuels. It's also nice the intake manifold paint does not burn off.

I have not tried it on early UPDRAFT carburetor system yet. Cynical, that It might be more sensitive.
Title: Re: Dies while idling and losing fuel from the fuel bowl
Post by: fishnjim on March 14, 2023, 01:24:23 PM
Lots of ideas, but no one can diagnose unknown, unseen equipment over the internet as we say.

some elementary Chem E:
Ethylene glycol(EG), aka anti-freeze depresses freeze point(FP).  So a 50:50 mix is the lowest freezing mixture, but it's not an even proposition at all percentage dilutions, ie: eutectic mixture - more than you woudl expect from the two.   There's a chart you can look up that describes this.
When one adds EG to depress FP, it changes the heat capacity of the mixture as EG, like most organics, has a much lower heat capacity than water.   1 vs ~0.4 say.   Therefore, EG absorbs less heat per unit(per pass) than water.
Q or heat = mass*Heatcapacity*temperaturedifferential
That affects the heat transfer coefficient and lessens cooling capacity slightly, but you're modern system is designed to handle that.  {Rate, Q/t, is proportional to heat transfer coefficient for the same area and temperature difference.}  Some of the early cars(pre-war) used plain water and they switched to alcohol in the winter.  There's was always the chance of not reacting in time and freezing the block, so EG was developed.  Low boiling alcohol tends to evaporate out so constant replenishment also required.
The boiling point increase comes from the pressurized system, which also prevents boiling at the surface.   There is some elevation due to the mixture as EG has a higher BP (197C), but not as much as it depresses FP.   That's a "molar" property so depends on molecular weight not weight/amount. EG:H20 ~3:1.  BP increases with pressure.
Title: Re: Dies while idling and losing fuel from the fuel bowl
Post by: VooDoo on March 14, 2023, 04:50:30 PM
Quote from: fishnjim on March 14, 2023, 01:24:23 PMLots of ideas, but no one can diagnose unknown, unseen equipment over the internet as we say.

some elementary Chem E:
Ethylene glycol(EG), aka anti-freeze depresses freeze point(FP).  So a 50:50 mix is the lowest freezing mixture, but it's not an even proposition at all percentage dilutions, ie: eutectic mixture - more than you woudl expect from the two.  There's a chart you can look up that describes this.
When one adds EG to depress FP, it changes the heat capacity of the mixture as EG, like most organics, has a much lower heat capacity than water.  1 vs ~0.4 say.  Therefore, EG absorbs less heat per unit(per pass) than water.
Q or heat = mass*Heatcapacity*temperaturedifferential
That affects the heat transfer coefficient and lessens cooling capacity slightly, but you're modern system is designed to handle that.  {Rate, Q/t, is proportional to heat transfer coefficient for the same area and temperature difference.}  Some of the early cars(pre-war) used plain water and they switched to alcohol in the winter.  There's was always the chance of not reacting in time and freezing the block, so EG was developed.  Low boiling alcohol tends to evaporate out so constant replenishment also required.
The boiling point increase comes from the pressurized system, which also prevents boiling at the surface.  There is some elevation due to the mixture as EG has a higher BP (197C), but not as much as it depresses FP.  That's a "molar" property so depends on molecular weight not weight/amount. EG:H20 ~3:1.  BP increases with pressure.
So if I'm understanding correctly, antifreeze has a lower heat capacity than water. Therefore water would cool better. What I'm not quite grasping is the boiling point vs heat capacity. If antifreeze has a higher boiling point than water, I had assumed a 50-50 mix with cool better because it wouldn't get as hot as fast due to the higher boiling point? Will water cool better because there's no organics in it but yet boil and evaporate out quicker than antifreeze? If so, one would just need to continually check and add water to the radiator if using straight water in theory?  Thank you for the chemistry analysis. Now I just need to make sure I understand it.🤣
Title: Re: Dies while idling and losing fuel from the fuel bowl
Post by: Paul on March 15, 2023, 10:47:55 AM
Andy, I had the same issue on my '59. The issue is Vapor Lock. The boiling point of fuel today is lower than it was back in the time your car was made. Therefore, you would want to install a fuel return line from the fuel bowl to the gas tank. When the engine heats up, it heats the fuel in the engine compartment and the fuel becomes a vapor, and therefore, isn't delivered to the carb, causing the engine to sputter and ultimately die out. The return line allows the fuel vapor to return to the tank and liquid fuel to flow thru to the carb.
You can install some heat shielding as an additional measure but it may not be enough to solve the issue alone. This was a common issue and was solved back in the 50's. You will see a lot of a/c Cadillac's have the fuel return line.
As far as coolant, if you live in the northern US, 50/50 will protect the engine year round and prevent it from freezing in the winter.
The issue you have with fuel is independent of the cooling system.
Title: Re: Dies while idling and losing fuel from the fuel bowl
Post by: VooDoo on March 15, 2023, 12:08:04 PM
Quote from: Paul on March 15, 2023, 10:47:55 AMAndy, I had the same issue on my '59. The issue is Vapor Lock. The boiling point of fuel today is lower than it was back in the time your car was made. Therefore, you would want to install a fuel return line from the fuel bowl to the gas tank. When the engine heats up, it heats the fuel in the engine compartment and the fuel becomes a vapor, and therefore, isn't delivered to the carb, causing the engine to sputter and ultimately die out. The return line allows the fuel vapor to return to the tank and liquid fuel to flow thru to the carb.
You can install some heat shielding as an additional measure but it may not be enough to solve the issue alone. This was a common issue and was solved back in the 50's. You will see a lot of a/c Cadillac's have the fuel return line.
As far as coolant, if you live in the northern US, 50/50 will protect the engine year round and prevent it from freezing in the winter.
The issue you have with fuel is independent of the cooling system.

I've been trying to read up on the Vapor lock. Seems like a vapor filter as you mentioned with a return line back to the tank. Would solve this. The filter if I'm understanding it correctly should go on the carburetor side of the fuel pump, correct? I was trying to keep the engine bay as original as possible and didn't really want to see a filter where one shouldn't be, but if I'm going to drive this thing a lot, it shouldn't really matter. Driving reliability should. It's  by not getting Judged. Just driven a lot. Same reason I'm contemplating a
12 V conversion vs a 6v Alternator to replace my warn generator
Title: Re: Dies while idling and losing fuel from the fuel bowl
Post by: Paul on March 15, 2023, 01:46:03 PM
Andy, if you are concerned with the look of the engine bay, that is certainly a valid concern.
I don't know of a fuel bowl (filter) for your car that supports a fuel vapor return line to the tank. There might be a version out there I am not aware of however.  An alternate solution would be to install a small electric fuel pump outside of the engine compartment on the fuel line from the tank. You would install an on/off switch in an inconspicuous place in the cab and use the electric pump when needed. This solution maintains the original look but will provide you with a solution to vapor lock.  Also, heat shielding may help keep the fuel lines cool enough to avoid vapor lock; belt and suspenders, so to speak.
Title: Re: Dies while idling and losing fuel from the fuel bowl
Post by: VooDoo on March 15, 2023, 01:54:13 PM
Quote from: Paul on March 15, 2023, 01:46:03 PMAndy, if you are concerned with the look of the engine bay, that is certainly a valid concern.
I don't know of a fuel bowl (filter) for your car that supports a fuel vapor return line to the tank. There might be a version out there I am not aware of however.  An alternate solution would be to install a small electric fuel pump outside of the engine compartment on the fuel line from the tank. You would install an on/off switch in an inconspicuous place in the cab and use the electric pump when needed. This solution maintains the original look but will provide you with a solution to vapor lock.  Also, heat shielding may help keep the fuel lines cool enough to avoid vapor lock; belt and suspenders, so to speak.

I actually do have an electric fuel pump that was installed by the previous owner. I figured out the other day that I can throw that switch. Turn it on when I'm idling and it solve the vapor lock. If I use this as a solution I just have to be aware That if I feel any thing funky in the idle, I need to throw the switch.  Kind of inconvenient to have to throw the switch, so I'll insulate the lines running from the fuel pump to the carburetor and see if that helps. As well. I read some thing about switching to a higher octane fuel because it has less alcohol in it? I'm out here in California, so I know gas  gets a bunch of additives and stuff in it especially during winter not sure if that plays a role or not
Title: Re: Dies while idling and losing fuel from the fuel bowl
Post by: Chopper1942 on March 15, 2023, 03:47:52 PM
Think of it like this: the ethlyene glycol has a higher boiling point than H2O. By mixing EG with H2O you lower the boiling point of the EG. H2O latent heat is much lower than EG so it gives up the heat easier. The stronger the mix the higher the boiling point of the mixture, but the engine can technically overheat because the heat is not given up by the stronger mixture.  The mixture under pressure raises the the boiling point of the water in the mixture. For each 1 pound of pressure increase over barometeric, the boiling point of H2O is raised 3 degrees.  Therefore, a #3 cap raises the boiling point of water to 221 degrees at sea level.  Today the radiator cap can be as high #22 and normal operating temps from 220-230 degrees. 

Back to your '37.  Do you live in cold climate- temps below freezing?  If so, do you drive in freezing temps or store the car in a freezing enviroment?  If you do, then a 50/50 mix is needed in the winter.  Otherwise, I would run distilled H2O.  Now then, just water in the system will lead to corrosion in the cooling system. When I lived in AZ, I found that many of the irrigation pump engines only ran water in the cooling systems.  They would run a pressure cap appropriate for the integrity of the radiator.  Too much pressure and you will damage the radiator.  To prevent corrosion in the engines, they used an additive.  Wix had an additive for diesel engines that prevented corrosion and prevented cavitation bubbles from damaging the cylinder sleeves.  I believe that the best option is to run water with an additive and a higher pressure cap.  For a thermostat, 180 is probably the best.  It will be hot enough to get rid of fuel and H2O in the oil. 

When I first started as a technician, when we would winterize a car, your choice was either glycol or alcohol.  Alcohol lowers the freezing point of H2O. We had a special hydrometer that had 2 floats. One side for EG and the other for the alcohol mix.  EG was very expensive then and alcohol was much cheaper.  The draw back to alcohol is its boiling point is much lower than water (173 degres), so you had to run a 160 thermostat to keep from boiling off the alcohol.  Not much heat from the heater at 0.  You also had to constantly check the coolant mix.  When you shut the engine off, even with a 160 stat, the heads, block, etc. are hot enough to boil the alcohol, because most pressure caps used at that time were 3-5 lbs.

I was born and raised in a small midwest town with a very prestigeous small liberal arts college. I had just started  working at a Cadillac-Oldsmobile-Chevrolet dealership. One fall day after a hard freeze, a college student from Chicago brought in his college car that his dad gave him.  It was his Grandfather's car that his dad had inherited.  The tanks were broken because the alcohol had evaporated out and it had no freeze protection. 

Don't cry.  It was a beautiful '34 Cadillac four door what I would call a phaeton.  Even then, it took a long time to find a replacement for him.  I install EG in it (his daddy could afford it)so it wouldn't freeze up and break the heads or block.

About the fuel vaporizing, get an inline filter with a return fitting.  Remove the OE line and make a new line to hide the filter behind the air cleaner, run the return line back to the tank and tie it into either the tank vent hose or the fill hosel

I know this was kinda windy but I hope it helps.
Title: Re: Dies while idling and losing fuel from the fuel bowl
Post by: Chopper1942 on March 15, 2023, 03:53:46 PM
I was writing a response and went to lunch when you responded about the electric fuel pump. Check its fuel pressure.  Make sure it isn't too much above the OE pressure.  If so, it could cause the engine to flood.  A fuel filter with a return would stop that if it happens.
Title: Re: Dies while idling and losing fuel from the fuel bowl
Post by: VooDoo on March 15, 2023, 03:55:16 PM
Definitely a wealth of knowledge... Thanks for the education.
Title: Re: Dies while idling and losing fuel from the fuel bowl
Post by: Poncholover on March 16, 2023, 08:38:19 PM
Skinny & Paul have it right. Fuel bubbles = boiling fuel. Cooling the fuel will help, a fuel return line will aid in doing this. Race or Av gas will help too.
Title: Re: Dies while idling and losing fuel from the fuel bowl
Post by: VooDoo on March 16, 2023, 08:45:43 PM
Quote from: Poncholover on March 16, 2023, 08:38:19 PMSkinny & Paul have it right. Fuel bubbles = boiling fuel. Cooling the fuel will help, a fuel return line will aid in doing this. Race or Av gas will help too.

Gotcha. Not quite sure where I can find race gas and don't know what a V gas is does that mean a higher octane fuel like 91 as opposed to 87 or is there a way to find alcohol, free gas?
Title: Re: Dies while idling and losing fuel from the fuel bowl
Post by: 35-709 on March 19, 2023, 08:51:07 PM
AV gas, short for aviation gas, it still contains lead and because it does it is illegal to use in an automobile.  If you can find it in your area, the best solution (IMO) is to use non-ethanol gas, also called "boat gas", as ethanol laced fuel will actually attack and ruin fiberglass gas tanks and is not good for many marine engines.  I use nothing but non-ethanol fuel in my older (without fuel injection) vehicles unless I am on a trip and am forced to use ethanol laced fuel.  Many stations carry non-ethanol these days and can be found at --- www.pure-gas.org 
Title: Re: Dies while idling and losing fuel from the fuel bowl
Post by: Chopper1942 on March 19, 2023, 09:16:34 PM
Most state still have straight unleaded fuel.  A lot of lawn & garden, power equipment, etc. can not use ethanol blended fuels because it is detrimental to diaphragms, fuel lines, gaskets, and plastics use in their fuel systems.
 
I don't know the price of leaded aviation gas, but Sunoco Race gas is about $675.00 for 54 gals. The cheapest way to go is to use Regular Unleaded gas, if available, and add Red Line Lead Substitute 60202 at $16.00 a bottle at Summit Racing.  It treats 25 gal of fuel.  Technically it is not to be used on road, but who will know.  It will also save your exhaust valves.
Title: Re: Dies while idling and losing fuel from the fuel bowl
Post by: VooDoo on March 19, 2023, 09:22:07 PM
Quote from: Chopper1942 on March 19, 2023, 09:16:34 PMMost state still have straight unleaded fuel.  A lot of lawn & garden, power equipment, etc. can not use ethanol blended fuels because it is detrimental to diaphragms, fuel lines, gaskets, and plastics use in their fuel systems.
 
I don't know the price of leaded aviation gas, but Sunoco Race gas is about $675.00 for 54 gals. The cheapest way to go is to use Regular Unleaded gas, if available, and add Red Line Lead Substitute 60202 at $16.00 a bottle at Summit Racing.  It treats 25 gal of fuel.  Technically it is not to be used on road, but who will know.  It will also save your exhaust valves.
I'm out in California and there's no alcohol free gas anywhere close to me. A V fuel seems very expensive. If that's the case, the additive you mention to regular unleaded fuel could be a good option. How will adding a lead additive to normal gas help with vapor lock?
Title: Re: Dies while idling and losing fuel from the fuel bowl
Post by: Chopper1942 on March 19, 2023, 09:43:39 PM
I don't know if it has any affect on the reid vapor pressure.  I would call Redline and talk to a tech.

Here is a link to white paper that explains a little about it.  https://www.redlineoil.com/Content/files/tech/Lead_Substitute__Tech_6.20_.pdf.

Red Line Synthetic Oil is open for business Monday through Friday, 7:00 a.m. to 3:30 p.m. PST.

Red Line Synthetic Oil
6100 Egret Court Benicia, CA 94510
Phone: (707) 745-6100 or (800) 624-7958
Fax: (707) 745-3214

Hope this helps.
Title: Re: Dies while idling and losing fuel from the fuel bowl
Post by: V63 on March 19, 2023, 09:59:45 PM
Since you are in a mild climate I will advocate for blocking the exhaust heating the carburetor feature. This can be done by separating the manifold and cutting a piece of stainless steel sheeting so to cover (block) all the heat passages surrounding the intake manifold.63EB320F-5A0C-48A9-B2DA-030EA9147C64.jpeg
Title: Re: Dies while idling and losing fuel from the fuel bowl
Post by: V63 on March 19, 2023, 10:10:54 PM
This is why the paint burns off the center of the intake manifold, the hot exhaust is BURNING it off, scorches it...eliminating this extreme  heat under your carburetor will go a long way in resolving your problem. 1CB40B3D-575B-4300-BB3F-2C8505D9BD7D.jpeg
Title: Re: Dies while idling and losing fuel from the fuel bowl
Post by: VooDoo on March 19, 2023, 10:14:10 PM
Quote from: V63 on March 19, 2023, 10:10:54 PMThis is why the paint burns off the center of the intake manifold, the hot exhaust is BURNING it off, scorches it...eliminating this extreme  heat under your carburetor will go a long way in resolving your problem. 1CB40B3D-575B-4300-BB3F-2C8505D9BD7D.jpeg
That's very interesting. I never realized that. Blocking it off has zero effect on how it runs etc.? I mean I'm sure it was there for a reason originally so just trying to understand how all those things work. I'm still learning quite a bit.
Title: Re: Dies while idling and losing fuel from the fuel bowl
Post by: V63 on March 19, 2023, 10:28:02 PM
I reside in Arizona and it's now a routine for me since these alcohol 🤬 related issues.
Olsons gaskets actually is making pre stamped versions the demand is increasing as people realize realistic solutions.
 I am blocking off my 1961 Chevrolet truck heat source (261 L6) as we speak.
The intake manifold will still get heated by osmosis to some degree, but not the nuclear heat it was getting.

We need to remember that driving demands were very much different, very short trips and also the focus was on extreme freezing  cold conditions rather than warm tempered conditions. The exhaust would certainly heat up very quickly and was greatly appreciated in -10F . There was no alcohol blended fuels to engineer around either.
Title: Re: Dies while idling and losing fuel from the fuel bowl
Post by: Chopper1942 on March 20, 2023, 08:01:43 AM
The exhaust passage in the intake manifold is there to help vaporize the fuel.  Any droplets of fuel are instantly vaporized when they hit the hot manifold below the carb.  Most application also utilize a heat riser valve to direct all the exhaust from going out the exhaust pipe to crossing over to the opposite bank, which heats the intake manifold.

The only detrimental issue is cold start and driving.  In cold weather, it will hesitate, may backfire, or die when you step on the throttle.  It will probably require choke application for a longer period of time.  Once warm, it should run just fine. 

I'm not familiar with the engine in your car.  Check the exhaust on both sides of the engine for a heat riser valve.  If it is stuck shut, it can cause a lot of driveability issues when the engine is at operating temperature: hesitation, stalling, vapor lock, and boiling the fuel out of the carb.  GM has a product that used to be called Heat Trap Lube and now is just their penetrating oil.  It is a penatrating oil with graphite.  It works great to free up and lube heat risers and other parts.  If your engine has a stuck heat riser and you can't free it up, take it out and cut out the valve, but leave the shaft.