![]() |
Register or Log In To remove these advertisements. |
|
|
![]() |
|
Thread Tools | Display Modes |
|
![]() |
#1 |
Registered User
Join Date: Sep 2008
Location: Gainesville Ga
Posts: 210
|
15 yr old son ask me a question I cant answer
When working on my 69 and trying to figure out the fuel delivery system, we was working on an idea for an in tank fuel pump. My son said, "let me get this straight, we're goin to run a hot wire down inside a gas tank and it wont blow up?" I said, son all of the newer vehicles have in tank pumps and weve changed out several of them over the years. He said, "but why dont it blow up?" I said, "son I have no idea nor have I ever thought about it." So Im bouncing it off you guys. Help me make sense of his question. I know you guys are goin to think Im crazy for some of the stuff Ive put on here.
Thanks. Last edited by Larry S; 02-01-2010 at 02:41 PM. |
![]() |
![]() |
#2 |
20' Daredevil (Ret)
![]() Join Date: May 2003
Location: Jefferson State
Posts: 13,637
|
Re: 15 yr old son ask me a question I cant answer
1) Gotta have oxygen to burn or explode.
2) It's in gasoline, so it can't spark, so it can't start a fire. 3) Gasoline can't burn. Gas vapor burns, but only in the correct air/fuel ratio.
__________________
- Mike - 1972 K20 LWB 350/350/205 RIP El Jay |
![]() |
![]() |
#3 |
Big Red - Now its a SWB!
Join Date: Jun 2009
Location: Oroville, Ca
Posts: 1,624
|
Re: 15 yr old son ask me a question I cant answer
also the fuel pump is insulated so the electricity doesn't flow through the gasoline.
__________________
68 3/4 ton ![]() ![]() 41 3/4 ton ![]() 01 Tahoe LT 4WD (my daily driver)-Magnaflow Muffler, Rollin on 22's 02 Ford Mustang Convertable (Wife's Car)-Flowmaster 50, Clear corners, Intake, sittin on 18's |
![]() |
![]() |
#4 |
Active Member
Join Date: Oct 2006
Location: Ohio
Posts: 1,643
|
Re: 15 yr old son ask me a question I cant answer
The fuel pumps are XP rated - XP = explosion Proof
The windings, seals and insulation all play a factor in achiving XP ratings.
__________________
1968 SWB 454 + .040, 490HP x 540 FT pounds of Torque 10-1 Kb Forged pistons, recon rods w/ ARP wave loc bolts 781 heads Ported with 2.19/1.88 SSTvalves Lunati 60204 cam, Micro Trol lifters, Ported Edelbrock Performer Rpm manifold armor coated, Pertronix Triple Strike Ignition Holley 770 Street Avenger carb,Headers armor coated Built by Watson Ruppel Performance in Sarahsville Ohio. Hardshift Tranny Built Turbo 350,TSI 10" 3000 stall 12 Bolt Eaton Posi 4.10 Richmond Gears moser axles ![]() 18.5" x 31" Hoosier Pro Street Radials ![]() ET Classic 5 Wheels - polished Power Steering, Power Brakes,Disc Brakes,Tach & Gauge Dash, Tilt,Factory Air (gone) Custom Paint & Body Work Special thanks to my wife, my son and my money tree ![]() |
![]() |
![]() |
#5 |
Registered User
Join Date: Jul 2009
Location: Farmington CT
Posts: 41
|
Re: 15 yr old son ask me a question I cant answer
Pumps are in explosion-proof housings as stated earlier. Also you are probably in the UEL or Upper Explosive Limit, too rich of a mixture for combustion. just like your carb if it is too rich the engine won't fire.
|
![]() |
![]() |
#6 |
Registered User
Join Date: Aug 2001
Location: rock island,il,usa
Posts: 5,382
|
Re: 15 yr old son ask me a question I cant answer
I thought would be goin a diff direction......when I was 15 yrs old(about 37 yrs ago), I asked my daddy a ? that he had a time answering! I asked, dad why are women so crazy? after a few stammers, the old man replied"you need to figure out if you need to live with them or not"! Well dad I dont think I can live without them
![]() ![]()
__________________
http://community.webshots.com/user/hotrodhorn |
![]() |
![]() |
#7 |
Registered User
Join Date: Jan 2010
Location: West Linn, Oregon
Posts: 10
|
Re: 15 yr old son ask me a question I cant answer
Besides what's already been stated, I'll add that they went to in-tank pumps because they are quieter and because the gasoline acts as a coolant for the pump motor. It's also harder on the pump internals to suck than it is to push - if a rotary pump has to suck a long distance before gasoline reaches it then the pump internals experience faster wear and higher temps before the cooling/lubricating gasoline reaches them.
|
![]() |
![]() |
#8 | |
Registered User
Join Date: Jan 2005
Location: Clearlake Oaks CA
Posts: 1,716
|
Re: 15 yr old son ask me a question I cant answer
Quote:
My Wife learned the Hard way, by overheating the Fuel Pump in her 97 Trans Am. Take Out the Driveline. Take Out The Rear End. Cut The Exhaust Put everything BACK together. $900.00 please............. We now go no lower than a 1/2 Tank on any of our Vehicles. ![]()
__________________
Hello members... I'd like you to know that I sold, my 72 GMC (Ratikle), back in November of 2011. I don't visit the site much anymore, but please feel free, to drop me a private message. RIP...."RATIKLE" |
|
![]() |
![]() |
#9 |
Special Order
![]() ![]() Join Date: Nov 2004
Location: Mt Airy, MD
Posts: 85,859
|
Re: 15 yr old son ask me a question I cant answer
How about an empty (virtually) tank?Your son has an inquiring mind.That`s a great thing.
__________________
"BUILDING A BETTER WAY TO SERVE THE USA"......67/72......"The New Breed" GMC '67 C1500 Wideside Super Custom SWB: 327/M22/3.42 posi.........."The '67" (project) GMC '72 K2500 Wideside Sierra Custom Camper: 350/TH350/4.10 Power-Lok..."The '72" (rolling) Tim "Don't call me a redneck. I'm a rough cut country gentleman" R.I.P. ~ East Side Low Life ~ El Jay ~ 72BLUZ ~ Fasteddie69 ~ Ron586 ~ 67ChevyRedneck ~ Grumpy Old Man ~ |
![]() |
![]() |
#10 |
blood type; Retumbo
Join Date: Jan 2004
Location: next to my reloading bench
Posts: 10,269
|
Re: 15 yr old son ask me a question I cant answer
you bring up a very important subject there. when you replace a fuel pump (in tank) you MUST have fuel in it before turning on the pump. I saw pictures of a shop (at least it used to be a shop) where a tech did it wrong. he turned the key on with an empty tank. the building is gone, tools gone, techs badly burned, customer vehicles destroyed. since that I ALWAYS disconnect the battery until I know for a fact the pump is submerged in fuel.
|
![]() |
![]() |
#11 |
Registered User
Join Date: Jul 2008
Location: Ukiah, ca
Posts: 4
|
Re: 15 yr old son ask me a question I cant answer
My opinion is A hot wire has no danger or real issue until it is connected, a loose hot wire wont catch a fire. Otherwise a batter would cause a fire just sitting near gas vapors, it has to ground to create a reaction, if groundedsolid and current is running it wont do anything. But if something is faulty and causes a spark and it's near the vapor, kaboooom...
|
![]() |
![]() |
#12 |
Registered User
Join Date: Mar 2008
Location: Lawrenceville, Ga
Posts: 300
|
Re: 15 yr old son ask me a question I cant answer
Remember TWA Flight 800. Atleast I do, at the time I was living on Long Island, Ny.
Unless you believe it was a missile strike that brought the aircraft down, the other theory is an explosion in a nearly empty fuel tank, the fuel vapors were ignited by an electrical short. http://en.wikipedia.org/wiki/TWA_Flight_800#Conclusions Last edited by Kayotic; 02-02-2010 at 09:10 AM. |
![]() |
![]() |
#13 | |
Registered User
Join Date: Feb 2000
Location: Center City, MN, USA
Posts: 3,254
|
Re: 15 yr old son ask me a question I cant answer
Quote:
So unless GM runs the starter wires with the fuel pump wires through the gas tank, we'll all survive. That flaming Chevy saddle tank on NBC was proven to be a ratings ploy by the network. They heard Chevy trucks with saddle tanks would blow up when hit on the side. They couldn't get it to work so they rigged a charge up to 'help' their arguement. A laywer with a sharp pencil slowed down the tapes and discovered the charge and made NBC shut up. Editted by Special-K
__________________
'70 cab, '71 chassis, 383, TH350, NP205. '71 Malibu convertible '72 Malibu hard top Center City, MN Last edited by special-K; 02-05-2010 at 09:16 PM. Reason: Did you a favor. |
|
![]() |
![]() |
#14 |
Registered User
Join Date: Jan 2006
Location: Take Off
Posts: 1,908
|
Re: 15 yr old son ask me a question I cant answer
I thought "Jap" was considered a bad word nowadays. I'm not Japanese but could see a person of Japanese descent being offended.
|
![]() |
![]() |
#15 | |
Registered User
![]() Join Date: Aug 2001
Location: SOMERSET KY.
Posts: 6,427
|
Re: 15 yr old son ask me a question I cant answer
Quote:
![]() ![]()
__________________
junkyardjohn 69 1 TON TOW TRUCK // 84 4WD CUCV BLAZER// 85 1 TON 4WD STAKE TRUCK// 86 M1031 5/4 TON 4WD CUCV// ALOT OF OLD TRUCKS FOR ONE OLD MAN TO DRIVE. ![]() LIFE MEMBER OF P.E.T.A (PEOPLE EATING TASTY ANIMALS) DON'T RENT U-HAUL ALWAYS TELL THE TRUTH IT WILL AMAZE PART OF THE PEOPLE & ASTONISH THE REST |
|
![]() |
![]() |
#16 |
Registered User
Join Date: Jan 2005
Location: Clearlake Oaks CA
Posts: 1,716
|
Re: 15 yr old son ask me a question I cant answer
Thread corrected in a non-political way.Please stay on topic and leave these judgements to staff.Thank you,Special-K
__________________
Hello members... I'd like you to know that I sold, my 72 GMC (Ratikle), back in November of 2011. I don't visit the site much anymore, but please feel free, to drop me a private message. RIP...."RATIKLE" Last edited by special-K; 02-05-2010 at 09:23 PM. |
![]() |
![]() |
#17 |
Senior Member
Join Date: Jun 2001
Location: Shelbyville, KY
Posts: 3,269
|
Re: 15 yr old son ask me a question I cant answer
All of the above is why I prefer placing the fuel tank as far away from the people as possible. There was a test years back that showed a chevy truck flipped on it's drivers side and slidding down the road. The fuel tank cap popped off spilling fuel and the whole thing basically when BOOM!! If you saw the film, you would immediately find a way to get that tank out of the cab!!!!!!!
Pumps push fuel easier then sucking but the primary reason was fuel injection. it requires a lot of pressure and a mechanical pump is not nearly as efficient--it also saps HP. Some vehicles have two push pumps--one in the tank and another prior to the injection. Either can fail and still run. Quickest way to ruin a in-tank fuel pump is to run the tank dry--pump overheats and dies. Another killer way is to run el-cheapo gas like Marithon---it had some substance that would kill fuel pumps. |
![]() |
![]() |
#18 |
Farmtruck desciple
Join Date: May 2009
Location: 90605
Posts: 158
|
Re: 15 yr old son ask me a question I cant answer
An explanation of "LEL" and "UEL" (flammability range of gasses in atmosphere)
http://www.mathesontrigas.com/pdfs/p...ve-Limits-.pdf Under normal conditions, it will be above the UEL. The danger is introduced with the addition of air or oxygen. Well placed electric fuel pumps will be in the base of the tank where vapors collect or submersed in the fuel. Well placed external plugs will be some distance from any openings (fillers or vents). 3 ft is a good margin of safety if the vehicle is worked on outdoors. |
![]() |
![]() |
#19 |
I am a Referee of life.
Join Date: Jun 2000
Location: Greensboro N.C.
Posts: 13,993
|
Re: 15 yr old son ask me a question I cant answer
I think the real answer is that the fuel pump is a sealed unit.Much like a submersible sump pump the electrical part of the unit is sealed from the liquid around it.Three phase and single phase pumps run underwater all the time in this configuration.The liquid still cools the unit but doesn't short it out.I don't know but assume that the fuel pumps in modern cars have the equivalent of a GFCI built in to prevent sparking ,thus preventing arcs that start fires.
__________________
The 47-present Chevrolet and GMC Truck Message Board Network,it's owners,moderators,members,and associates of any type should not be held responsible for my opinion. You can't fix stupid,not even with duct tape. "My appearance is due to the fact that "GOD" does punish you for having too much fun!" Barrett-Jackson has perfected alchemy,they make rust into gold! "You can lead a horse to water but you can't saddle a duck" "Cleverly disguised as a 'Responsible Adult' "Sometimes your Knight in shining armor is just a retard in tinfoil" |
![]() |
![]() |
#20 |
slowest. build. ever.
![]() Join Date: Jan 2009
Location: SF East Bay Area
Posts: 28
|
Re: 15 yr old son ask me a question I cant answer
what I thought even more interesting was, I believe, gasoline does not conduct electricity the way water does. I had an instructor in automotive school that used to race electric rc cars and he would wear in his new motors by running them full speed while submerged in gasoline.
the gas would provide just the right lubrication and cooing while still allowing the brushes to "burn in" (bad choice of words) and he would actually get performance increases. by the way, I've never actually seen this done, so I'M NOT RECOMMENDING ANYTHING, NECESSARILY. |
![]() |
![]() |
#21 |
blood type; Retumbo
Join Date: Jan 2004
Location: next to my reloading bench
Posts: 10,269
|
Re: 15 yr old son ask me a question I cant answer
|
![]() |
![]() |
#22 |
Registered User
![]() Join Date: Sep 2003
Location: DFW
Posts: 765
|
Re: 15 yr old son ask me a question I cant answer
they are not sealed, but you will have a very hard time getting an explosive mixture of air and gas to the brushes. the gas tank will generally be at or above the upper explosive limit as far as the "mixture" inside the tank. the vapor is what burns not the liquid.you have to have an ignition point that is of sufficient temperature to ignite the fumes. I have personally seen cigarette butts thrown into drainbuckets that have contained many a flammable mixture in them. nothing thankfully has happened, it comes down to Flash point, and mixture percentage. but introduce a spark or flame,poof.
Disclaimer: Do not try extinguishing cigarettes in buckets of gasoline or paint thinner. Be a little smarter. Unless your gene pool is that murky, if you do then do not blame me
__________________
The problem with America is stupidity. I'm not saying there should be a capital punishment for stupidity, but why don't we just take the safety labels off of everything and let the problem solve itself? |
![]() |
![]() |
#23 |
blood type; Retumbo
Join Date: Jan 2004
Location: next to my reloading bench
Posts: 10,269
|
Re: 15 yr old son ask me a question I cant answer
Edited by staff:
You`re alright.I just edited the crap that started this hijack causing counter comments. ![]() Last edited by special-K; 02-05-2010 at 09:26 PM. |
![]() |
![]() |
#24 |
Registered User
Join Date: Jun 2007
Location: South Carolina
Posts: 106
|
Re: 15 yr old son ask me a question I cant answer
I thought about the fuel pump thing when I had to replace one and had to replace the fuel pump pig tail with a newer design. I usually solder and heat shink or tape. Oviously was worried bout tape or heat shrink in the gasoline not to metion the open flame to do the deed. I ended up using the supplied butt connectors. Most mention the pump its self blowing up, I think the most likely thing would be a loose connection which can cause enough heat to burn up a connector and a low tank of gas.
|
![]() |
![]() |
#25 |
Registered User
Join Date: May 2009
Location: Salisbury, NC
Posts: 24
|
Re: 15 yr old son ask me a question I cant answer
If Ford Rangers get made overseas there will never be one in my driveway. I may start rethinking all those new F-250's I have been buying for the last ten years.
Last edited by Todd327; 02-05-2010 at 01:17 PM. |
![]() |
![]() |
Bookmarks |
|
|