Engine Left On....While Refueling?

[winkosmosis]

It does get quite a bit hotter when the engine is off. I have a mechanical temp gauge. If the engine is idling.. and the temp is 190, I can turn the engine off, let it sit 5-10 mins, come back and crank it, and it will be at 200-210.

Sounds like the coolant is getting hotter, as it absorbs heat from the engine but has nowhere to get rid of it. The engine itself won't get any hotter htough.

 

[winkosmosis]

All the gas stations in this area would freak if you left it running while refueling. I even had this lady yell at me because I was filling gas cans in a trailer instead of on the ground.

That has happened before. Static builds up and discharges from the trailer or pickup bed into the nozzle, because the tires are insulating it from the ground. Some documentary, can't remember what, showed footage of that happening.


http://www.cdc.gov/niosh/hid2.html

In recent incidents reported to the National Institute for Occupational Safety and Health (NIOSH), fires spontaneously ignited when workers or others attempted to fill portable gasoline containers (gas cans) in the backs of pickup trucks equipped with plastic bed liners or in cars with carpeted surfaces. Serious skin burns and other injuries resulted. Similar incidents in the last few years have resulted in warning bulletins from several private and government organizations.
These fires result from the buildup of static electricity. The insulating effect of the bed liner or carpet prevents the static charge generated by gasoline flowing into the container or other sources from grounding. The discharge of this buildup to the grounded gasoline dispenser nozzle may cause a spark and ignite the gasoline. Both ungrounded metal (most hazardous) and plastic gas containers have been involved in these incidents.

Here's some footage:
http://www.youtube.com/watch?v=1tYO4jvnJHw

 

[whatevah]

the engine may not generate heat itself, but the stupid pre-cats on the downpipes put off a ton of heat! Well, that's their job, burn off the unused fuel... which produces heat. That's why my engine temp will climb to 240 after I shut it off at 210, got a soda from the local 7-11 and started it back up.

It's 9am and already 88* outside, hopefully when I get up at 4pm to get ready for work, it won't kill me to run the engine for a bit to aim my infrared temp gun at the precats and see how hot they get.

it was just too hot yesterday, but I just checked... aimed the gun at the shield around one of the precats, 680*. So, you've got almost 700* temperatures (presumably more if you're driving...) rising up and literally baking everything on the drivers side of the engine compartment. Sheesh, during the rare times I use the oven at home to bake something, it's usually only 350-400*.

 

[scavengerj]

My thoughts are that yes, there may be a temperature increase under the hood, but it is not of such a prolonged period that it would do very much harm. I mean we're talking about just filling up. What about, for those of us without a fan switch/timer who drive for hours and then park the vehicle. Surely there is a temp rise due to limited/no air flow, but there isn't any more heat being generated then is already there.

As pointed out, the signs state what they do for a reason. It may not likely happen, but then again do I want to chance it...no. I worked at a station and used to put my butts out in a cup of gas just to show people that it wasn't the liguid that burned it was the vapor.

Surely on a hot, dry, no air movement, summer day with mulitple vehicles fueling and vapors wafting in the air, there very well may be the likelyhood that a vehicle left running could possibly cause a fire.



DMS #525
AMSA #1102
OBPA

 

[winkosmosis]

The heat originates in the cylinders. The reason there may be a temp increase somewhere else like the coolant sensor is that heat is being conducted outward as the engine cools. There isn't some magical source of heat that keeps burning when you shut the engine off.

 

[kastein]

The heat originates in the cylinders. The reason there may be a temp increase somewhere else like the coolant sensor is that heat is being conducted outward as the engine cools. There isn't some magical source of heat that keeps burning when you shut the engine off.

Actually there is... it's the catalytic converter.

 

[89xj]

so if i keep the engine running while at quick stops at the store or getting gas(which i never do, except once and got a warning from a cop), i should get another 100K miles on my 89 that already has 250K miles?

i think if its an issue for your xj, i would install a timer or temp controller to the efan or just put in some hood vents.

there is something to this as new cars will turn on the electric fan after the engine is turned off and the temps rise too much, at least my wifes toyota matrix does.

 

[89xj]

Actually there is... it's the catalytic converter.

and depending where you live, in the summer time the heat of just the black top/asphalt can be over 100 degrees which will lengthen the cooling time of the cat convertor/engine/underhood temps.

 

[joe_peters]

Follow the laws in your area.

 

[stephenspann27]

Sounds like the coolant is getting hotter, as it absorbs heat from the engine but has nowhere to get rid of it. The engine itself won't get any hotter htough.

My temp probe is inline on the upper radiator hose, just behind the A/C compressor, with the engine off, no coolant is not circulating, and the temp probe.. being mounted in a hose.. is not "absorbing heat from the engine."

My '87 has its cat mounted below the passenger seat.. and I still get the same heat build up as you guys with pre cats.

 

[stroked88]

Uh... what?

if you leave jeep idling for a long period, not enough air flows through condensor to cool freon charge, which also helps keep compressor cool. compressor gets hot and messes up bearings. idling the engine up to about 1200 rpm will help flow more air to keep this from happening, and if you dont want to do this then you can just turn off the a/c so that the compressor isnt turning. Make sense?

 

[collkid]

Since our engines reach their highest temperatures immediately after they are shut down and the cooling systems are stopped - therefore making short idles less damaging to the engine than frequent on-and-offs - does anyone leave their engine on while refueling?

I know for newer cars, the entire fuel system is pressurized, including the tank, and will cause engine alerts if the cap is even removed while the engine is running.

It sounds a little extreme, but won't it help the long-term care of our engines?

PS - I dont do it....yet!

Thanks


David
'99 4.0, 145k miles

I Drive just under 1,000 miles a Month between my Escort and my Jeep. When its cold out I ALWAYS leave the cars running while fueling. And, if I'm on the go, I leave it running too.

Never had a problem, been doing it for a few years now.

 

[winkosmosis]

My temp probe is inline on the upper radiator hose, just behind the A/C compressor, with the engine off, no coolant is not circulating, and the temp probe.. being mounted in a hose.. is not "absorbing heat from the engine."

My '87 has its cat mounted below the passenger seat.. and I still get the same heat build up as you guys with pre cats.

Then where do you think the heat is coming from??

 

[stroked88]

:quote:Then where do you think the heat is coming from??:quote: the engine. when the coolant doesnt circulate it just absorbs more of the heat at once. the engine itself doesnt actually get hotter. the water just absorbs extra heat and since its not circulating it cant release it through the radiator. if you will notice after it sits about 10-15 minutes when you first start it the temp will be the same reading but then after the water gets moving (couple seconds) the temp drops below operating temperature

 

[winkosmosis]

:quote:Then where do you think the heat is coming from??:quote: the engine. when the coolant doesnt circulate it just absorbs more of the heat at once. the engine itself doesnt actually get hotter. the water just absorbs extra heat and since its not circulating it cant release it through the radiator. if you will notice after it sits about 10-15 minutes when you first start it the temp will be the same reading but then after the water gets moving (couple seconds) the temp drops below operating temperature

That's what I'm saying

 

[TerraWombat]

In NJ where we don't pump our own gas, we get yelled at by the attendants if we don't shut our engines off. In the summertime, It's funny hearing the yuppie soccer moms complain that their A/C doesn't work in their giant Lexus SUVs when the engine is off.

 

[SteveT]

Here's a simple solution: Check your oil every time you fill up. Lets out all that pesky heat, plus you keep tabs on your engine.

I really think you're over thinking this. Shut off your engine, hot or cold outside, doesn't matter. Extended idling is a waste.

 

[stephenspann27]

Here's a simple solution: Check your oil every time you fill up. Lets out all that pesky heat, plus you keep tabs on your engine.

I really think you're over thinking this. Shut off your engine, hot or cold outside, doesn't matter. Extended idling is a waste.

I rebuilt my engine about 10 months ago, but I still raise the hood weekly and go over the entire engine.. electrical connectors, wires hoses, check all fluids.. I'm paranoid something is getting a hole rubbed in it or something touching the exhaust manifold etc... Afraid I have something routed wrong.

Its a good practice to check things often on older high mileage vehicles..

 

[winterbeater]

We solved the problem of people fueling up their cars with the engine running. When YOU get to the back of the car to fuel, somebody jumps in the front and takes your wheels.

Nobody fuels with the engine running in Detroit!

 

[stephenspann27]

if you leave jeep idling for a long period, not enough air flows through condensor to cool freon charge, which also helps keep compressor cool. compressor gets hot and messes up bearings. idling the engine up to about 1200 rpm will help flow more air to keep this from happening, and if you dont want to do this then you can just turn off the a/c so that the compressor isnt turning. Make sense?

BTW.. there are only two bearings in the compressor.. one in the clutch that only spins with the compressor is disengaged, and the ther is just behind the main seal.. there is no way refrigerant keeps either bearing cool..