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Scorching Hot afternoon, at least 110F, black wagons like to get even hotter. Wife was passenger and we both needed cool so had the AC running hard (AC is custom with later model rotary and super oversized condenser). Headed north on Freeway-5 from Los Angeles up the Castaic uphill grade where big sign says "AVOID OVERHEATING TURN OFF AIR CONDITIONER NEXT 6 MILES". Too hot to obey the sign. Never drove with this much heat with AC up this grade but '84 240 wagon automatic has 352k miles, my failsafe workhorse car for 26 yrs. Saw lots of stalled cars and tow trucks on shoulder. Temperature gauge stayed below 10 o'clock with aux fan running. Engine simply quit 200ft before top of grade, no drama. Almost made it. I thought I heard it say "Thats it boss, this is too much, I need a break". Probably need to discuss this with my doctor but that belongs to a different forum. Luckily there was a shade tree. After a 30-minute rest by the side of the freeway, engine restarts and we get to continue our journey (with AC of course). Good to know that vapor lock can happen to this car, the better to prevent it from happening.
Btw, just finished a trip to Calgary and Jasper, 5k miles in 3 weeks, and did not ever need to add any oil. Same on another recent trip to NM and CO. Amazing gutless wonder. I havent posted here in about 10 yrs. My last post was when I lost brakes going down Bristlecone forest from 10k feet on a hot day. Fluid boiling points are lower at high elevation. Passenger was my girlfriend now wife.
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You said the engine "simply quit..."
In my experience, there are usually two kinds of engine quit: if it's a lack of fuel (pump failure, relay, fuse, etc) the engine will stumble for a second or two as pressure falls, before dying. If it's ignition, the failure is immediate, as if you'd turned off the switch. If that latter describes your issue on the Castaic, perhaps things got so hot under the hood that the Hall sensor in the distributor, or the ICU needed a cooldown?
--
Bob: Son's XC70, my 83 244DL, 89 745 (Chev LT-1 V8), 98 S90 (recently sold) and 2010 XC60. Also '77 MGB and four old motorcycles
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I have never in my 20 years of Volvo ownership heard of vapor lock occurring on a RUNNING fuel injected car. I would be more apt to suspect a fuel pump relay issue or an overheated fuse holder, coil, in tank fuel pump (considering the grade less than half a tank could show this issue), etc.
Vapor lock in any car is most likely to occur when you stop after a hot run and fuel boils in section inside the engine bay.
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In my 26 yrs driving this same car, never saw it happen. Fuel level was full so unlikely to be the cause. I have driven numerous times in hotter temperatures >120F but under lower throttle settings. Same car a few days later I drove from Needles to Barstow during one of CA hottest days. The heat was unbelievable but no issues came up.
Clearly the underhood temperatures must have been extremely high, exacerbated by the AC use.
There were a lot of stalled cars by the shoulder that hot afternoon. Many were recent model within 10yrs. When I called for a tow, AAA said they were inundated by calls on that stretch of road that afternoon and I will have to wait. I cancelled my request when the car restarted after the 30 min rest. I might also suspect the most recent incarnation of CA fuel might have something to do with this.
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Ok, I do not think I was direct enough...you cannot have vapor lock with in excess of 50 psi fuel coursing through those lines lines. Assuming the the 50 PSI were stagnant and there was no fuel flow, the fuel temp would have to exceed 260f to boil.
Please, look for potential other causes that could bite you down the road.
Those new cars...they went into limp home mode and did not have the umph to make it up said hill in that mode. So many things in a modern ECU/PCM/BCM.
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Very good Onkel, thanks but I know what you are saying. I believe underhood temperatures were easily over 212F that afternoon. Engine was in full throttle for about 6 miles uphill 3rd gear when it happened, and in heavy traffic with AC before that. I suspect 260F was possible.
Fyi, when the incident occurred pulling off the highway, there were so many stalled cars I parked right behind another one.
Car wouldn't start after about 5x attempts. After a 3-minute wait, still wouldn't start after about 5x attempts. 30 minutes later, car started after about 2x attempt. Incident occurred 2 months ago. The car has done more than 4k miles since and in even hotter temperatures except more level roads. Still runs fine every time up to now. I haven't seen anything suspect so this is why I am posting.
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Vapor lock is indeed very easy to encounter in a 240. Been there. Done that.
Here's the t-shirt:
http://cleanflametrap.com/tranferPump.htm
--
Art Benstein near Baltimore
“Always code as if the guy who ends up maintaining your code will be a violent psychopath who knows where you live.” - John F. Woods
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getting a 404 error but I think I know what this one is about so please let me know if it is the simple lack of an "s".
This where the in-tank pump rubber coupler is failed or the in tank pump failed?
Those were among my suggestions (thought forgot to specifically name the coupler) as this is not just "fuel got too hot" vapor lock which is virtually impossible to form post fuel tank in a currently running fuel injected car.
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Sorry for the 404. At least you got one worthy of affixing to your trunk.
If you work the list from email, you aren't seeing the latest edit, which fixes the extension from .html to .htm.
Anyway, the point is you can run on a dead tank pump for years, literally, without being aware it is dead. Until it gets hot, your fuel is low, or you climb a mountain. Assemble all three and you're doomed to multiple cool-off rest stops.
OP said nothing about the tank pump, so it was a slam dunk. I know of two stories where a 240's dead tank pump on a mountain trip was part of a premarital romance -- premarital as in engagement. Now I am aware of one which includes brake failure! We love the grandchildren. :-)
In The Tank
Vapor lock is not just a heat factor, it is a combination of that and pressure differential. And if you get locked into carburetor thinking, you have the idea it has to occur under the hood. The main pump creates negative pressure on the intake from the tank. The tank pump needs to make it positive again.
--
Art Benstein near Baltimore
If speed counted, rabbits would rule the world.
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In-tank pump is an IPD unit which is stronger than stock. Recent test (after the incident) it draws 4.0 amps with engine running. This pump is so strong it can push a spray thru a pinhole on the rubber hose leading to main pump.
I have no doubt a pump can cause vapor lock (I've seen it on a different vehicle) but I've repeatedly driven this car in much hotter temperatures and there was never a problem so it seems the pump can be ruled out.
I suspect the vapor occurred in the injectors. The high duty cycle after 6 miles of full throttle contributed.
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Maybe it quit when you needed it most. They do become intermittent, especially with wear at the commutator. IPD really does sell that thing as an "upgrade." :)
There's no way vapor lock can occur any place but between tank and main pump input as long as the main pump is working. That's what Onkel Udo said and he's right. Could be that the main pump got too hot and quit or more likely it lacked electricity or fuel for input.
Is your 84 the B23F normally aspirated model? I had the same symptoms once on what seemed like a 110 degree day at a sane altitude driving an 83 turbo as a result of the typical poor connections at the k-jet fuel relay and fuse panel. Without full battery, the pump dies, and runs again when things cool off.
Also with a Regina (single pump in the tank) symptoms mimicking vapor lock occurred when the brush braid strap broke and its spring had to serve as its conductor. What a hellish trip that was.
Did you continue with the HC refrigerant in your York replacement? Still holding up after 10 years?
--
Art Benstein near Baltimore
Grandchildren are God's reward for not killing your own children.
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Yes normal B23F.
My evidence seems to rule out a pump. Less than 2k miles on main pump and filter when incident occurred. A few days after the incident, car was driven twice on record hot afternoons between Barstow and Needles. Those were the days when the 'Blue Cut' wildfire near Wrightwood occurred due to record heat and dry about 120F. Since I-40 is not as busy and more level, throttle settings were easier. Also did Kelbaker to Amboy in the inferno of Mojave with AC running so hard that mileage dropped below 20mpg. Fuel tank got very hot but again no problems. I drive the Castaic grade all the time on this car. Just did it yesterday and today but it was only 97F and didn't see stalled vehicles on the shoulder.
The HC on the York did very well. However the York always had problems, the last was a worn clutch so I took it out and put in a rotary from an 86. Ran HC on the new rotary and it worked well too but its now on R134 with this living experiment. I think the bottleneck with the 240 AC is the evaporator being too small, constrictive, and prone to freezover. The blower is also weak and noisy compared to modern designs. The choice of refrigerant played only a small part in my bottom line.
Glad to see the old names still hang around the forum.
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I have been thinking about carbs again as we are trying to tune the OEM, 70 year old Ball and Ball carb in the 1948 Plymouth. That one is fun as there are only two main jet sizes left and you are suppose drill out the smaller as needed if the larger is too big. Luckily, flatheads run almost exactly the same moderately rich as they do with a perfect mixture.
Also fun is ignition timing where the spec's are originally designed for about 70-75 octane fuel. Tuning by ear and nose are the order of the day.
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