Engine: Anti Vapor Lock Device

[Pckstude]

Have any of you seen something like this? It looks professionally done. I'm told the car originated in Texas, so that would explain this because of the heat. Was it an after market kit? Do you think if someone made these people would buy them?

[StudeRich]

Ya just gotta wonder if it would deflect more heat than it attracts.
Just a creative DIY'er.

NICE Battery !

[Mike Van Veghten]

Yeah, I'd say it might work. Just a odd looking radiator ! Just like the plate that GM put under many of the carburetors of some of their "racier" engines.
I know that the 69 Z-28 had them from the factory.

Mike

[gordr]

Looks home-made to me, but nicely made. Notice the three oil filler caps? Guessing the engine was tired, and had a lot of blowby. And a vapor bubble on the pressure side of the fuel pump doesn't cause vapor lock, anyway. It's when you get a vapor lock on the suction side that the fuel delivery stops.

[JoeHall]

I support this idea, and also experienced much improvement while living in the desert, when I once installed an aluminum shield on a Stude, as in Mike's picture above. Blocking the rising heat from the motor goes a long way toward reducing vapor lock. And I'd say both of the above ideas, combined together, would be very helpful. Those mods are ugly, but it's a function over form situation. IMHO

[altair]

I am out in left field on this subject and I am wearing a bullet proof (resistant) vest. There is no such thing as a vapor lock, what kills the engine, is the gasoline in the fuel bowl boils over and over fuels the engine. Fuel pumps are positive displacement pumps and are therefore not effected by air displacement, what is on one side of the diaphragm will be moved to the other side be it air or liquid. Test it for yourself, connect a rubber hose 10 feet long full of air into a container of liquid gasoline or solvent and pump it by hand, it will displace the air and pump the liquid there will not be any vapor lock. For every engine that died in a traffic jam because of a dead battery, running out of fuel, overheating, fuel boiling in the carb and over fueling the engine were all called VAPOR LOCK by the media. Fuel boiling over can be caused by several issues firstly poorly maintained cooling system ie overheating, stuck or improperly installed heat riser, spark modifier malfunction(spark retarded) low coolant, stuck thermostat or too high a rated thermostat, over working an engine and not allowing time to cool before shutting down ie climbing a grade and shutting off at the top before letting it cool down, this will boil everything and you won't restart for 1/2 -3/4 hr.

[Big Dan]

Oh, here we go again! LOL!

[enjenjo]

So what is the condition called when the fuel in the line from the tank to the pump vaporizes fast than the pump can pump it?

[JoeHall]

Too bad you were not in charge at the S-P Corp in 1951, when they put out a Service Bulletin on "VAPOR LOCK IN FUEL SYSTEM IN HOT WEATHER - 1951 COMMANDER (H) MODELS". In that SB they mentioned remedying air leaks in the fuel system, fuel line routing, and defective fuel pumps. They put out another SB on VAPOR LOCK in the late 1950s, but I am too lazy to look it up. You coulda schooled them on what the problem really was, and on proper verbiage to describe it.

Maybe "heat related fuel problems" would satisfy you better? Having lived in the California desert for six years, and drove only Studes back then, I agree with the Stude SBs, and would add here's actually a myriad of heat related fuel problems, from tank to carburetor, including carb percolation and after-boil. I'll add there are several ways to reduce the problem(s), but the only CURE I ever found was to install EFI. The OP shows yet another way to reduce the problems, as does Mike's pic.

Thanks for trying to school us all though. LOL

[altair]

If every radio station in the nation broadcasts the conditions as Vapor Lock and every person that hears it also believes such a condition exists you have thousands of people believing the radio stations. A large corporation like Studebaker would not counter the claim but except it and fabricate a cure. To this day what is the cure?
I will tell you about a parallel situation, I was a fire commissioner inspector and there was a serge of dryer fires where people had removed a hot garment from the dryer and didn't restart it. The pending fire inside the dryer consequently damaged the dryers wiring harness and therefore the fire cause was determined to be faulty wiring when it never was. This information was forwarded back to the manufacturer who didn't counter the determination they just offered a new design of wiring harness when it was never the problem in the first place.

[Lark Hunter]

altair - Unless I'm misunderstanding you, I think I'ma have to disagree with you on the dryer fire situation. As I'm reading it, the wiring was damaged because the dryer was stopped suddenly while the heating element was on to remove a garment instead of running through the end of the cycle on the timer, which operates a cool-down sequence where the element is powered off while the blower continues to run for a couple minutes to make sure the element and its heating chamber cool down before the cycle ends and the dryer shuts off. Yes, opening the door and stopping the dryer mid-cycle will hotbox the heating element and create a localized hot spot within, but the wiring should have been routed so that it isn't affected by this action. If they weren't willing to do this, there should have been a door lock that wouldn't allow the dryer to be quickly shut down and opened up before the element cool-down cycle had completed.

[bensherb]

I doubt the metal shields will have much affect in the long run. Once you've been on the road a while the underhood temp rises to the same temp as the coolant. At least according to the underhood temp meter I have on my GT. It's particularly bad on the C/K because the firewall leans rearward creating a pocket to trap hot air around the top and above the engine. I remove the cowl seal so hot air can escape, it in turn also lowers coolant temp. Louvers in the hood would also do the same. I added an electric system to raise the rear of my hood 2", it works surprisingly well to lower underhood and coolant temps.

To cure fuel heating problems I routed the fuel line out of the engine compartment. It enters through the inner fender and runs directly to the carb. The 18" of line in the engine compartment floats above and away from any metal and is insulated. Problem solved.

[altair]

I will stand my ground as long as I am above ground on this subject. To this day, the only confirmed cure is fuel injection.

[Lark Hunter]

I don't think I've ever experienced vapor lock... or if I have, it wasn't bad enough to remember. I've experienced a little bit of goofy running after a heat soak, like a puff of black smoke, a little bit of surging or a lean bog for maybe 15-30 seconds. Everything always smoothed out and went back to normal with little fuss.

FWIW- I have only owned two EFI vehicles. The gasoline in one of them would occasionally boil on very hot days when you removed the gas cap... Same car also boiled the fuel while I was on a trip to Montana. I found this as I was driving through Kingman, AZ late at night, and I could hear a strange whining noise coming from the rear of the car... It actually built up enough pressure that it was lifting the pressure relief valve built into the plastic gas cap, which was what was making the sound. The engine stalled as soon as I removed the cap, and the gasoline started boiling furiously. I figured out that the in-tank pump was failing, slowly grinding itself to pieces. Somehow managed to limp it to MT, but it was kind of a hairy trip. Also got gasoline boiling in the float bowl on a 1981 Pontiac when the thermo-vacuum switch that controlled the heat riser failed with it in the closed position.

Like gordr said, the fuel in the lowest pressure area is what will boil first. Any time you've got a liquid trying to turn into a gas while it's running through a system designed strictly for moving liquids, it's not optimal. The Lumina I mentioned above was probably the closest I got to vapor lock, though the car did start back up after I screwed the cap back on, and managed to herk and chuggle me down the road... and temporarily got better once I reached Cedar City, UT and the ambient temps dropped back down. Probably one of the few times an EFI vehicle would start suffering like that, though remember it was on the low pressure side of the fuel supply before it entered the pump. Now that I've gloated a bit, my carbureted truck will probably conk out in traffic tomorrow just to smite me.

[Hawklover]

Ya just gotta wonder if it would deflect more heat than it attracts.
Just a creative DIY'er.

NICE Battery !

Nice cobwebs:-)

[Hawklover]

I am out in left field on this subject and I am wearing a bullet proof (resistant) vest. There is no such thing as a vapor lock, what kills the engine, is the gasoline in the fuel bowl boils over and over fuels the engine. Fuel pumps are positive displacement pumps and are therefore not effected by air displacement, what is on one side of the diaphragm will be moved to the other side be it air or liquid. Test it for yourself, connect a rubber hose 10 feet long full of air into a container of liquid gasoline or solvent and pump it by hand, it will displace the air and pump the liquid there will not be any vapor lock. For every engine that died in a traffic jam because of a dead battery, running out of fuel, overheating, fuel boiling in the carb and over fueling the engine were all called VAPOR LOCK by the media. Fuel boiling over can be caused by several issues firstly poorly maintained cooling system ie overheating, stuck or improperly installed heat riser, spark modifier malfunction(spark retarded) low coolant, stuck thermostat or too high a rated thermostat, over working an engine and not allowing time to cool before shutting down ie climbing a grade and shutting off at the top before letting it cool down, this will boil everything and you won't restart for 1/2 -3/4 hr.

Excellent points!

[JoeHall]

I don't think I've ever experienced vapor lock... or if I have, it wasn't bad enough to remember. I've experienced a little bit of goofy running after a heat soak, like a puff of black smoke, a little bit of surging or a lean bog for maybe 15-30 seconds. Everything always smoothed out and went back to normal with little fuss.

FWIW- I have only owned two EFI vehicles. The gasoline in one of them would occasionally boil on very hot days when you removed the gas cap... Same car also boiled the fuel while I was on a trip to Montana. I found this as I was driving through Kingman, AZ late at night, and I could hear a strange whining noise coming from the rear of the car... It actually built up enough pressure that it was lifting the pressure relief valve built into the plastic gas cap, which was what was making the sound. The engine stalled as soon as I removed the cap, and the gasoline started boiling furiously. I figured out that the in-tank pump was failing, slowly grinding itself to pieces. Somehow managed to limp it to MT, but it was kind of a hairy trip. Also got gasoline boiling in the float bowl on a 1981 Pontiac when the thermo-vacuum switch that controlled the heat riser failed with it in the closed position.

Like gordr said, the fuel in the lowest pressure area is what will boil first. Any time you've got a liquid trying to turn into a gas while it's running through a system designed strictly for moving liquids, it's not optimal. The Lumina I mentioned above was probably the closest I got to vapor lock, though the car did start back up after I screwed the cap back on, and managed to herk and chuggle me down the road... and temporarily got better once I reached Cedar City, UT and the ambient temps dropped back down. Probably one of the few times an EFI vehicle would start suffering like that, though remember it was on the low pressure side of the fuel supply before it entered the pump. Now that I've gloated a bit, my carbureted truck will probably conk out in traffic tomorrow just to smite me.

Using "vapor lock" as generic for heat related fuel problems, I only recall one Stude that did not vapor lock when living in the California desert, a 65 DAYTONA SS, with 283 motor. It may have, but I do not recall, though we drove it about 25,000 miles while there. I recall a 64 Wagonaire with 259, and OEM 2B carb, that would begin to idle rough and only kept running at around 1500 RPM; I discovered the idle would smooth out if I blew into fuel filler neck, but only briefly. I recall a newly rebuilt 56J motor that ran a bit warm during breakin, and the electric fuel pump would begin chattering around 225 degree engine temps, and the motor would need to run at least 1500 RPM to avoid dying. Generally, all Studes would begin to vapor lock at around 225 degrees, but steady 210 temps was never a problem, and that's where most of them ran in summer there. I recall stopping to refuel on a hot summer day in the desert, and pressure buildup in the 62GT's tank sufficient to make the gas cap hard to twist off, and blew it back into my hand upon release. I instinctively looked below the gas tank, and discovered the rubber hose, that attaches the metal fuel line to the tank nipple, was only holding on by about 1/2"; the tank's pressure had almost pushed it off the nipple. After that, I vented all Stude fuel caps to vent both in & out.

A good demo of Stude vapor lock, on a mass scale, was a parade in South Bend at an SDC-IM, about 15-20 years ago. It was unusually hot and traffic was heavy, so there was a lot of stop & go, and about 1/3rd of the Studes (1940s - 1960s, V8s and sixes) puttered to the side of the road (or stalled in the middle of the road), and hoods went up everywhere. It was comical. IMHO, anyone who has never seen a Stude vapor lock has simply never drove them enough in hot weather, under the right (wrong) conditions.

[JoeHall]

Here in Kentucky, the biggest PITA with vapor lock is hot restarts, after the motor is shut off 20-40 minutes in hot weather and the carb becomes heat soaked. I cured it on both GTs by installing EFI, in 2012 and 2013. The 56J has always been a PITA for hot restarts, especially with the OEM WCFB. Over the decades, I have ran AFB, Holley 4160, Holley 4360, and Holley Demon, and the only carb that all but cured it was the Demon, but the MPG was terrible. The recent swap to another AFB, with 1/2" wooden spacer / insulator, seems promising, but real hot weather is not here yet to know for sure. I plan to reinstall the AC on it soon; the WCFB was so terrible with hot restarts, I did not reinstall the AC after the 352 rebuild, but will now, since the AFB is doing so good.