Very detailed explanation. I’m sure there are a people who are interested to learn all about electric fuel pumps. It’s hard to look for videos like these so thank you for uploading it and satisfying people’s curiosities.
Great video. It was nice to see the actual disassembled pump and to hear about the check valve, as that is something I needs attention on one of my vehicles.
@knunne1 Thanks for that great comment, I'm actually looking into going back to Airtex to do some more of these videos so that is one request I hope to fill.
Thanks to Airtex and ETCG for a great video. I am amazed at how, what is basically plastic and a motor can deliver combustible fluid so reliably. Hats off to Airtex's Engineering & Production's teams and their quality! I am guilty of not recognizing how hard and trouble free fuel pumps work. I enjoyed seeing how the Car's trouble symptoms related to the components in the pump and the various versions made as well as how they are tested. Again Great Video, more please!
This video defiantly confirms that I have a fuel injector problem with my truck and not a fuel pump check valve problem because of the bleed off time that my fuel pressure gauge was showing. When I tested my truck the pressure bled off immediately after shutting the truck off.I'm looking at getting new injectors and I know now its not the pump.Great video Eric and thanks for all the info.
Eric this video has come in handy. I'm in the middle of a GM fuel pressure diagnosis and just how he explained the check valve and everything else has given me such a better understanding of the pump. Thanks and I'm literally still dirty...
@TheTexasCoder That is very true, I like to get my info from the source whenever I can and this guy is about as close to the source as you can get from what I've seen. Thanks for the comment.
awesome video. I have been trying to find out why my 02 jeep wont start on the first try. people kept telling me its the fuel regulator that has the check valves. even the dealer couldnt tell me for sure, they just tell me to change everything 650.00! I will buy the airtex pump assy and put it in. Thanks for the great video Eric!
@brian5446 Either that or you can just cycle the key before you crank the engine when you go to start the car, I did that for years on a car that I used to have as the pump still worked fine.
@alundrasrt No need to worry about that as the pump is submerged in the gas in the tank which is what 'lubricates' (if you could call it that) and cools the assembly, priming it is not necessary at least with the pumps I've installed.
Great video! Thank you AirTex and EricTheCarGuy...I love technical shows like this. Eric, all I have to say, after watching Curt's reactions to your questions, that man has FORGOTTEN MORE ABOUT FUEL PUMPS then you and I will ever learn :-)
This guy is such an engineer. When he's talking to Eric he's looking at the disassembled fuel pump while answering the question and not even looking anywhere near Eric. The machines interest him more.
@Begbucks Yes they did have a very extensive diesel section at the facility, I didn't spend a whole lot of time there on this trip, perhaps the next if I get the opportunity.
@Bushougoma No, in fact the fuel flows right through the pump. Remember in order for combustion to take place you need O2 and if the pump is full of fluid there is no O2 for combustion to occur.
Cool video. Not something you usually think might be stopping your car from starting, until you see this and cross reference it with the symptoms your car is having. Luckily mine is still OK, but not fun to replace if yours is in need of repairs. Thanks for teaching me another thing about cars I might need if it stops working. :-)
Great video! Very informative. That's why I never try to drive my vehicles passed 1/4 if I can prevent it. Driving towards flat E is the primary reason fuel pumps fail prematurely!
Thank you so much for sharing Eric! Wow, I believe the pressure relief valve went bad in my factory fuel pump. (2001 Chevy Cavalier 2.2). I hope you don't mind me sharing this but - I have never seen this before or I have not found any information on this type of fuel pump failure. I'm having a no start condition. I have spark everywhere spark should be. Testing the pump; the pump sound was normal, I could hear the pump running just fine. I found very low fuel flow, pressure at the filter, but not much fuel volume, I found it pumped about 1/2 quart in 5 minutes, when it should flow about 1 quart in 30 seconds. I very carefully removed the fuel pump and energized the fuel pump motor, the gas pressure was shooting out of the motor's top housing hole and barely going through the fuel line. I guess I have to replace either the pump or the fuel pump assembly.
Sure would be nice if you guys made a pump that mounted OUTSIDE the fuel tank, perhaps inside a metal cage to protect it. The fuel could still flow-through for cooling. The ability to replace these things is now limited to few diys or an expensive trip to the shop. Airtex guy did a beautiful presentation. Wish I was that good !
@beefystik well that's what i understand from your comment , we all like the guy and i can tell you i have watched most of his videos maybe excepts the FATR's and i never remember he ever asked this or complained from repeated questions ! On the Contrary !! he always answer comments no matter how silly or lean or repeated they are! he even answers comments after while that makes you think he will never get back to them but he always does ! .
Goodness, that's extremely complex! Its amazing these things don't fail more often. I've never owned a car that had a fuel pump fail until recently my 92 Astro van fuel pump started working intermittently. Kick the gas tank once or twice and it works again. Finally decided to change it. See this is why people want electric cars. wayyyyyyy fewer parts to fail lol.
@tinydx95t2 I wouldn't condemn an injector right off if you don't have a problem with the way the engine runs, normally if an injector is that bad you will have a very wet spark plug and a misfire on the effected cylinder. You might want to try your test with the return line pinched off as it could be a fuel psi regulator problem. Good luck.
Now I see why modern designs incorporate a fuel filter proximal to the pump, to keep debris from clogging the pump turbines. Too bad the new fuel filters are so hard to get to....
I find it fascinating and a little counterintuitive that the brushes are submerged in gasoline with the rest of the pump. The brushes on most motors show visible spark, and those brushes on the fuel pump look smaller but similar. The only thing missing seems to be oxygen, and when the tank runs dry there will be air in the tank, too. Am I missing something?
I wonder if We change that "bag" or filter pick up it would help our pumps last longer since it wouldn't have to work so hard as it gets dirty...nice vid man! Im looking for your coolant vid haha
@EricTheCarGuy Well that's it Eric the truck hesitates horribly at times then it takes off like a bat out of hell.I pm you about that before and made sure it wasn't a timing chain. My next step is to start pulling plugs and to try and find the bad injector.
@MrOne2watch It does sound like a possible check valve issue but use a fuel pressure gauge to confirm it. As for Airtex pumps I've never had a problem with them. I don't have a video on that particular replacement at this time sorry.
Notes: In many of these fuel pumps, there are a PAIR of one-way check valves. One is to maintain fuel pressure in the downstream fuel lines so as to keep from having long cranking times when you come back in the morning. The other check valve is for pressure relief in case the system is building up too much pressure for normal operation, it just bleeds off through the check valve which is oriented to release the excess pressure just below the normal system operating pressure. However, if a piece of debris gets caught in the rubber "seat" of the check valve, or the rubber of the check valves seat deteriorates over time sufficiently, the fuel pressure will bleed off in a certain amount of time when the vehicle is not in use. When you look at the top of the fuel pump and you see two different electrical connectors, one is of course for the power supply and the instrument cluster gauge, and the other is likely the electrical connect for the vapor sensor for the fuel tank.
good video. last week i destroyed two of this type of motors to know what is there inside mees how it pumps fuel when it submerged in fuel. but you given good description about this motors. thanks.
It helps to have a visual representation like this, and a "plain english" explaination of each component. I can't learn shit from just a bunch of text, a have to at least see a video like this, but I prefer to actually get my hands on it at some point.
they know alot about pumps for people that can't build one that works. I had one doa. pushed 12psi new out of the box. second one I used lasted 25 miles and broke down on the side of the highway. I laid in gravel and broken glass to replace it with pos Carter pump that cost half as much and lasted 6 months. first two times I just needed to get by a few days, and they didn't even last that long. the Carter pump was the only one I could get same day where I was broke down. BTW, airtek pumps were both all plastic drive mechanisms with thinner teeth then the brass assembly in the OEM Bosch and Carter pump. the airtek that lasted 25 miles was also really loud and pulled nearly 20 amps, the Carter pulled 9.6 amps while actually pumping. even though the airtek couldn't start the car, it did have enough left in it to pump 10 gallons out of my full tank before I smashed it with a rock and left it with the broken glass. this time I'm special ordering a walbro. the first one lasted 28 years and 320k miles, not minutes.
Great clip,thanks. Is anyone able to answer a question which comes to mind while watching this; the float /level rheostat and the motor brushes and armature setups both appear to have active voltage circuits and (to me) apparent potential for arching or sparking.the fuel even passes THROUGH the motor ! Obviously this is a completely safe feature ,but I can't quite understand how these functions are included IN the actual tank,with no regard for a possible ignition of the fuel? Any explanation would be appreciated. Thanks in advance.
Can't be just me, I have had several of these in a suburban, I drip the tank, clean the tank, replaced with a life time warranty Airtex ( I bought it when there was still lifetime warranties on these thank goodness) worked great for about 5 months and poof, gotta get a new one. 1997 suburban, 5 airtex pumps before I sold the truck off. 4 failures in 4 years not counting the last one I sold the truck off with or the first one that was OEM. I didn't have to clean the tank after that 1st time since it was clean as can be. the filters were not clogged, the just quit working. I am currently working in a GMC Yukon and decided to try a AC Delco. I am curious to see if it's works better.
@paul06660 If it's the original pump it's not likely that it's bad, in fact OE Honda pumps hardly ever go bad. You say the pressure is 40psi, but have you checked it during the extended crank? If not you might as the pump may be good but the check valve may be stuck not keeping pressure on the system after shut off. Lastly I HATE aftermarket distributors as I've seen nothing but problems with them, you may want to check your timing.
Most interesting video on the internet right now. I just can't find one about the transistor fuel pumps and why a universal on an 85 Nissan pickup keeps loosing fuel pressure from the tank up to the engine. I'm almost 100 percent sure it needs an inline check valve after the pump. I really think the auto parts store forgot that some filters used to double as a check valve. I don't understand why it's a discontinued part either it seemed to have a good purpose
@donbehatin I have. I did a test with a fuel pressure gauge and I performed the test 6 times in a row and 4 out of the 6 times I performed the fuel pressure test the pressure leaked off.Plus I have been changing my oil about once a month because the oil smells like gas. I have great compression so its not rings.and I've looked at the rest of the fuel system and everything is good.The only 2 things that would cause readings like what I got is a faulty check valve or injectors.
@EricTheCarGuy What if you had an empty tank with just vapor in it? Couldn't that be an explosion hazzard if you get a spart or arc from the pump motor?
If the check valve is bad, then the hot engine starting gets difficult. The fuel pressure is lost quickly and with a hot engine, this results in fuel vapours forming in the fuel lines. This leads to hot engine restart a little longer.
Great video. Is there a way to test a used fuel pump motor to see how strong it is? I guess put it in the tank, do KOEO and KOER pressure tests at the rail then leave it over night to see if the check valve holds the pressure?
@lol123321123321 That sounds like a check valve issue. Normally when pumps go bad they just don't run and cause a condition of no fuel pressure. I actually have another video with Airtex covering that procedure, How To Diagnose A Fuel Pump Failure.
I love Eric's videos, I'm watching the belt and pulley basics video, I think hmm how does a fuel pump work then? And itheres a video on the topic right in the sidebar! Haha so many vids
I've seen fuel pumps many times, but this vid made me realize just how small the actually impeller assembly is....Pretty amazing to think that something so small does so much for so long....(I'm sure there's a lewd joke in there somewhere!).
Thanks for this. I just replaced a fuel pump. Old one had definitely failed. After 20 perfect kilometers on the new pump it started running rough, no power, slow to build revs and hard start. I have 55psi at the rail but an almost instant pressure drop. There are no leaks and I've checked the pressure regulator and its working. I assumed a failing pressure check valve in the pump but after this Im thinking maybe the regulator only looks like its working... hmmmmmmmmmm
I have a 96 F250 w 60,000mi it has dual tanks. I'm experiencing low fuel pressure on both tanks. Front tank @18 psi and rear tank @ 28 psi. Both tanks hold pressure for awhile but not over night. Should I replace both pumps or is there a way to find out which pump is the problem? Great video by the way!
Thx alot Eric! I have an older saab, and I've found the most notorious part in my car is the fuel pump. I have been getting longer starts - about 6 seconds now - so its good to get some evidence of the fp from someone who knows them. Does a defect in the check valve mean replacement?
@poopsmashed forgot to add - of course if your tanks ruptures and fuel leaks then it's a whole different story. it's dangerous in any way and it's probably not worth discussing it at all :)
Is there a quality pump (motor) I can swap into my sending unit (airtech doesn't seem to be in business anymore)? Backstory, I really thought OEM would have been great but seems it's not what it used to be. I'm having a HELL of a time with a factory / OEM replacement fuel pump. I swapped out simply cause was old, preventative maintenance. I'm on my second OEM pump in 2 years. I keep going back and forth with the manufacturer that wants me to check various things but I've went through the line set, electrical circuit, regulator, injectors, rail, cannot find any other faults anywhere. Long story short, it's running 7 PSI lower than spec.
"I have a question about fuel pump design. I was wondering why fuel pumps are designed to use the fuel itself as a lubricant and coolant. Why is this so? Most other electric motors I've seen don't need any cooling to operate continuously. Also, since fuel is going through the motor brushes, wouldn't there be a spark there while the electric motor is spinning? Wouldn't that ignite the fuel? I don't know much about these things..." most electric motors have a lubricant inside them, unfortunately gasoline acts as a solvent and washes off the lubricants. So the pumps are designed to use gasoline as a lubricant instead. Many fuel pump motors are quite powerful for their size, and run at 100% duty cycle (the run continuously) and will overheat without a constant flow of cool fuel. Most electric motors that run for extended periods with 100% duty cycle have some form of cooling. also keep in mind some electric motors are air cooled without a fan and may or may not use a heat sink to aid in cooling depending on how much heat they put out. Liquid gasoline and diesel is non flammable. In fact assuming there is no vapors sitting on top of the fuel you can throw a lit match into a bucket of gasoline and it will put out the match. Gasoline VAPOR on the other hand is highly flammable when combined with oxygen. To burn 1 liter of VAPORIZED gasoline it needs to be mixed with approximately 15 liters of air to provide the requisite oxygen for complete combustion. For these reasons there is no concern of igniting the fuel from the spark caused by the electric fuel pump.
your fuel tank won't ignite just because of the sparking from pump rotor/stator. there's a lot of O2 in the gas tank (gas tanks usually have a bleed valve on the cap to let air in when fuel goes down). it's the ratio that does the magic. luquid fuel in a closed container hardly ever ignites. it's the fumes that do it, for one litre of gas you need 14.7 litre of air. theoretically there's only one sweetspot and that's when you're really empty. but you need VAPOR not liquid in order for it to expl
You explained all components and functionality in under 10 min, and most importantly you answered all my questions.... Well done sir!
Very detailed explanation. I’m sure there are a people who are interested to learn all about electric fuel pumps. It’s hard to look for videos like these so thank you for uploading it and satisfying people’s curiosities.
This is why I love your channel - very educational stuff, and you don't try to dumb it down like some other shows do.
Great video. It was nice to see the actual disassembled pump and to hear about the check valve, as that is something I needs attention on one of my vehicles.
@knunne1 Thanks for that great comment, I'm actually looking into going back to Airtex to do some more of these videos so that is one request I hope to fill.
Thanks to Airtex and ETCG for a great video. I am amazed at how, what is basically plastic and a motor can deliver combustible fluid so reliably. Hats off to Airtex's Engineering & Production's teams and their quality! I am guilty of not recognizing how hard and trouble free fuel pumps work. I enjoyed seeing how the Car's trouble symptoms related to the components in the pump and the various versions made as well as how they are tested. Again Great Video, more please!
Mr. Ulm is well spoken. I especially liked how he described the actual components in detail.
Interesting... If there were more people like you the world would be a better place... I like your passion and dedication... Keep it up
This video was very helpful in understanding the function of the electric fuel pump and how each component works.
This video defiantly confirms that I have a fuel injector problem with my truck and not a fuel pump check valve problem because of the bleed off time that my fuel pressure gauge was showing. When I tested my truck the pressure bled off immediately after shutting the truck off.I'm looking at getting new injectors and I know now its not the pump.Great video Eric and thanks for all the info.
Eric this video has come in handy. I'm in the middle of a GM fuel pressure diagnosis and just how he explained the check valve and everything else has given me such a better understanding of the pump. Thanks and I'm literally still dirty...
@TheTexasCoder That is very true, I like to get my info from the source whenever I can and this guy is about as close to the source as you can get from what I've seen. Thanks for the comment.
awesome video. I have been trying to find out why my 02 jeep wont start on the first try. people kept telling me its the fuel regulator that has the check valves. even the dealer couldnt tell me for sure, they just tell me to change everything 650.00! I will buy the airtex pump assy and put it in. Thanks for the great video Eric!
Now I don't need to take mine apart to see how it works. You saved me a afternoon and maybe a fuel pump! Thanks
@aodhanof90 It's nice to get information direct from the source. Thanks for the comment.
@95ACM It's a common problem but as you can see the pump will still function without it but it will cause extended crank times.
Very clear description of all the parts and what they do
@brian5446 Either that or you can just cycle the key before you crank the engine when you go to start the car, I did that for years on a car that I used to have as the pump still worked fine.
@alundrasrt No need to worry about that as the pump is submerged in the gas in the tank which is what 'lubricates' (if you could call it that) and cools the assembly, priming it is not necessary at least with the pumps I've installed.
@barrioalto100 Glad you like them, thanks for the comment.
Great video! Thank you AirTex and EricTheCarGuy...I love technical shows like this. Eric, all I have to say, after watching Curt's reactions to your questions, that man has FORGOTTEN MORE ABOUT FUEL PUMPS then you and I will ever learn :-)
This guy is such an engineer. When he's talking to Eric he's looking at the disassembled fuel pump while answering the question and not even looking anywhere near Eric. The machines interest him more.
Thanks! Now I know where the check valves at. Always informative!
@pathosbedlam Your most welcome and thank YOU for the comment.
@Begbucks Yes they did have a very extensive diesel section at the facility, I didn't spend a whole lot of time there on this trip, perhaps the next if I get the opportunity.
@Filmaker25 That sure does help but the #1 cause of failure according to the people that I talked to was contamination of the pump with debris.
@Bushougoma No, in fact the fuel flows right through the pump. Remember in order for combustion to take place you need O2 and if the pump is full of fluid there is no O2 for combustion to occur.
Eric your channel is top-notch.
@1967800 That is the exact reason for these videos. Thanks very much for your comment.
Cool video. Not something you usually think might be stopping your car from starting, until you see this and cross reference it with the symptoms your car is having. Luckily mine is still OK, but not fun to replace if yours is in need of repairs. Thanks for teaching me another thing about cars I might need if it stops working. :-)
Eric, Great video, very informative. Thank you for all your hard work in shooting these videos, we need more like you in this business.
@1PossumJenkins Great information thanks for your comment.
Great video! Very informative. That's why I never try to drive my vehicles passed 1/4 if I can prevent it. Driving towards flat E is the primary reason fuel pumps fail prematurely!
Thank you so much for sharing Eric! Wow, I believe the pressure relief valve went bad in my factory fuel pump. (2001 Chevy Cavalier 2.2). I hope you don't mind me sharing this but - I have never seen this before or I have not found any information on this type of fuel pump failure. I'm having a no start condition. I have spark everywhere spark should be. Testing the pump; the pump sound was normal, I could hear the pump running just fine. I found very low fuel flow, pressure at the filter, but not much fuel volume, I found it pumped about 1/2 quart in 5 minutes, when it should flow about 1 quart in 30 seconds. I very carefully removed the fuel pump and energized the fuel pump motor, the gas pressure was shooting out of the motor's top housing hole and barely going through the fuel line. I guess I have to replace either the pump or the fuel pump assembly.
@Sum2021 That's why I'm here, thanks for the comment.
Sure would be nice if you guys made a pump that mounted OUTSIDE the fuel tank, perhaps inside a metal cage to protect it. The fuel could still flow-through for cooling. The ability to replace these things is now limited to few diys or an expensive trip to the shop.
Airtex guy did a beautiful presentation. Wish I was that good !
@TeDuaMalakie Remember it's immersed in gas so no air can get to it, you can't have combustion without O2.
That guy knows his pumps!
@beefystik well that's what i understand from your comment , we all like the guy and i can tell you i have watched most of his videos maybe excepts the FATR's and i never remember he ever asked this or complained from repeated questions ! On the Contrary !! he always answer comments no matter how silly or lean or repeated they are! he even answers comments after while that makes you think he will never get back to them but he always does ! .
Goodness, that's extremely complex! Its amazing these things don't fail more often. I've never owned a car that had a fuel pump fail until recently my 92 Astro van fuel pump started working intermittently. Kick the gas tank once or twice and it works again. Finally decided to change it. See this is why people want electric cars. wayyyyyyy fewer parts to fail lol.
@tinydx95t2 I wouldn't condemn an injector right off if you don't have a problem with the way the engine runs, normally if an injector is that bad you will have a very wet spark plug and a misfire on the effected cylinder. You might want to try your test with the return line pinched off as it could be a fuel psi regulator problem. Good luck.
great question about check valve symptoms!
Awesome video, very good explanation of how fuel pump works.
@nightmathzombieethan Indeed there is, thanks for the comment.
Very cool. Very detailed and helpful. Thanks Eric!
Now I see why modern designs incorporate a fuel filter proximal to the pump, to keep debris from clogging the pump turbines. Too bad the new fuel filters are so hard to get to....
I find it fascinating and a little counterintuitive that the brushes are submerged in gasoline with the rest of the pump. The brushes on most motors show visible spark, and those brushes on the fuel pump look smaller but similar. The only thing missing seems to be oxygen, and when the tank runs dry there will be air in the tank, too. Am I missing something?
spelunkerd my same concern or question,, how does that dont ignite the fuel??
I wonder if We change that "bag" or filter pick up it would help our pumps last longer since it wouldn't have to work so hard as it gets dirty...nice vid man! Im looking for your coolant vid haha
very good break down
It's best not to know how complicated something like this is. Just more things to worry about going wrong.
Great VID!!!!! Always wondered how a fuel pump works.
Marc
Great video! Always wanted to know whats inside.
@dandroz240 They make those there too, I hope to go back and show how those work next time.
@EricTheCarGuy Well that's it Eric the truck hesitates horribly at times then it takes off like a bat out of hell.I pm you about that before and made sure it wasn't a timing chain. My next step is to start pulling plugs and to try and find the bad injector.
@MrOne2watch It does sound like a possible check valve issue but use a fuel pressure gauge to confirm it. As for Airtex pumps I've never had a problem with them. I don't have a video on that particular replacement at this time sorry.
EricTheCarGuy z
@sbakar Hard to say, perhaps the clearances are at their limits or it's got contamination of some kind.
Good job Eric, that's really cool
Notes: In many of these fuel pumps, there are a PAIR of one-way check valves. One is to maintain fuel pressure in the downstream fuel lines so as to keep from having long cranking times when you come back in the morning. The other check valve is for pressure relief in case the system is building up too much pressure for normal operation, it just bleeds off through the check valve which is oriented to release the excess pressure just below the normal system operating pressure. However, if a piece of debris gets caught in the rubber "seat" of the check valve, or the rubber of the check valves seat deteriorates over time sufficiently, the fuel pressure will bleed off in a certain amount of time when the vehicle is not in use. When you look at the top of the fuel pump and you see two different electrical connectors, one is of course for the power supply and the instrument cluster gauge, and the other is likely the electrical connect for the vapor sensor for the fuel tank.
good video.
last week i destroyed two of this type of motors to know what is there inside mees how it pumps fuel when it submerged in fuel.
but you given good description about this motors.
thanks.
@DrJerryrigger I do what I can, thanks for the comment.
@chopywatersofmantuki I'm sure there are but you should be able to clean it out, at least that's what I've done in the past.
@xmtc87x I love what I do so it's not hard at all. Thanks for the comment.
It helps to have a visual representation like this, and a "plain english" explaination of each component. I can't learn shit from just a bunch of text, a have to at least see a video like this, but I prefer to actually get my hands on it at some point.
they know alot about pumps for people that can't build one that works. I had one doa. pushed 12psi new out of the box. second one I used lasted 25 miles and broke down on the side of the highway. I laid in gravel and broken glass to replace it with pos Carter pump that cost half as much and lasted 6 months. first two times I just needed to get by a few days, and they didn't even last that long. the Carter pump was the only one I could get same day where I was broke down.
BTW, airtek pumps were both all plastic drive mechanisms with thinner teeth then the brass assembly in the OEM Bosch and Carter pump. the airtek that lasted 25 miles was also really loud and pulled nearly 20 amps, the Carter pulled 9.6 amps while actually pumping.
even though the airtek couldn't start the car, it did have enough left in it to pump 10 gallons out of my full tank before I smashed it with a rock and left it with the broken glass.
this time I'm special ordering a walbro. the first one lasted 28 years and 320k miles, not minutes.
Yeah a whole lot of plastic in this video. Nobody cares about making stuff last anymore... Or perhaps they design them to fail.. more likely IMO.
@30GB No I don't think you can as it was not designed to move a fluid that thick or that hot.
@Jx1x3 I don't think that would make much difference really but I've never tried it so I don't know.
Great clip,thanks. Is anyone able to answer a question which comes to mind while watching this; the float /level rheostat and the motor brushes and armature setups both appear to have active voltage circuits and (to me) apparent potential for arching or sparking.the fuel even passes THROUGH the motor ! Obviously this is a completely safe feature ,but I can't quite understand how these functions are included IN the actual tank,with no regard for a possible ignition of the fuel? Any explanation would be appreciated. Thanks in advance.
Can't be just me, I have had several of these in a suburban, I drip the tank, clean the tank, replaced with a life time warranty Airtex ( I bought it when there was still lifetime warranties on these thank goodness) worked great for about 5 months and poof, gotta get a new one. 1997 suburban, 5 airtex pumps before I sold the truck off. 4 failures in 4 years not counting the last one I sold the truck off with or the first one that was OEM. I didn't have to clean the tank after that 1st time since it was clean as can be. the filters were not clogged, the just quit working. I am currently working in a GMC Yukon and decided to try a AC Delco. I am curious to see if it's works better.
@paul06660 If it's the original pump it's not likely that it's bad, in fact OE Honda pumps hardly ever go bad. You say the pressure is 40psi, but have you checked it during the extended crank? If not you might as the pump may be good but the check valve may be stuck not keeping pressure on the system after shut off. Lastly I HATE aftermarket distributors as I've seen nothing but problems with them, you may want to check your timing.
Good video.
@tookimonster333 I actually asked that very question in the other video the Engineering Tour.
Interesting. Thanks so much
Most interesting video on the internet right now. I just can't find one about the transistor fuel pumps and why a universal on an 85 Nissan pickup keeps loosing fuel pressure from the tank up to the engine. I'm almost 100 percent sure it needs an inline check valve after the pump. I really think the auto parts store forgot that some filters used to double as a check valve. I don't understand why it's a discontinued part either it seemed to have a good purpose
@donbehatin I have. I did a test with a fuel pressure gauge and I performed the test 6 times in a row and 4 out of the 6 times I performed the fuel pressure test the pressure leaked off.Plus I have been changing my oil about once a month because the oil smells like gas. I have great compression so its not rings.and I've looked at the rest of the fuel system and everything is good.The only 2 things that would cause readings like what I got is a faulty check valve or injectors.
Outstanding ....love to know what I'm working on
Absolutely fascinating.
thx, great video! i just didnt understand how the heavy duty pump works... have to think about that :)
thx again!
@EricTheCarGuy What if you had an empty tank with just vapor in it? Couldn't that be an explosion hazzard if you get a spart or arc from the pump motor?
If the check valve is bad, then the hot engine starting gets difficult. The fuel pressure is lost quickly and with a hot engine, this results in fuel vapours forming in the fuel lines. This leads to hot engine restart a little longer.
Great video. Is there a way to test a used fuel pump motor to see how strong it is? I guess put it in the tank, do KOEO and KOER pressure tests at the rail then leave it over night to see if the check valve holds the pressure?
@lol123321123321 That sounds like a check valve issue. Normally when pumps go bad they just don't run and cause a condition of no fuel pressure. I actually have another video with Airtex covering that procedure, How To Diagnose A Fuel Pump Failure.
I love Eric's videos, I'm watching the belt and pulley basics video, I think hmm how does a fuel pump work then? And itheres a video on the topic right in the sidebar! Haha so many vids
I've seen fuel pumps many times, but this vid made me realize just how small the actually impeller assembly is....Pretty amazing to think that something so small does so much for so long....(I'm sure there's a lewd joke in there somewhere!).
muy buenos videos eric
Thank you for this great video it was very informative.
Wish you would have done a video between a good airtex pump and a cheap pump found from a random seller on ebay or amazon.
Get a Delphi or Carter, not Airtex!
@Ibringthetruth1 Feel free to stop by anytime.
Hey that was a great video Eric, thanks for putting that together :-)
Thanks for this. I just replaced a fuel pump. Old one had definitely failed. After 20 perfect kilometers on the new pump it started running rough, no power, slow to build revs and hard start. I have 55psi at the rail but an almost instant pressure drop. There are no leaks and I've checked the pressure regulator and its working. I assumed a failing pressure check valve in the pump but after this Im thinking maybe the regulator only looks like its working... hmmmmmmmmmm
Pretty cool. Thumbs up.
I have a 96 F250 w 60,000mi it has dual tanks. I'm experiencing low fuel pressure on both tanks. Front tank @18 psi and rear tank @ 28 psi. Both tanks hold pressure for awhile but not over night. Should I replace both pumps or is there a way to find out which pump is the problem?
Great video by the way!
Thx alot Eric! I have an older saab, and I've found the most notorious part in my car is the fuel pump. I have been getting longer starts - about 6 seconds now - so its good to get some evidence of the fp from someone who knows them. Does a defect in the check valve mean replacement?
EXCELENTE VIDEO.. FELICIDADES.!
@poopsmashed forgot to add - of course if your tanks ruptures and fuel leaks then it's a whole different story. it's dangerous in any way and it's probably not worth discussing it at all :)
Good video explanation
Is there a quality pump (motor) I can swap into my sending unit (airtech doesn't seem to be in business anymore)? Backstory, I really thought OEM would have been great but seems it's not what it used to be. I'm having a HELL of a time with a factory / OEM replacement fuel pump. I swapped out simply cause was old, preventative maintenance. I'm on my second OEM pump in 2 years. I keep going back and forth with the manufacturer that wants me to check various things but I've went through the line set, electrical circuit, regulator, injectors, rail, cannot find any other faults anywhere. Long story short, it's running 7 PSI lower than spec.
crazy how many little parts are inside the fuel pump
If you keep your fuel level up is that all you need to do to keep the fuel pump going? How many miles should you get with any fuel pump?
"I have a question about fuel pump design. I was wondering why fuel pumps are designed to use the fuel itself as a lubricant and coolant. Why is this so? Most other electric motors I've seen don't need any cooling to operate continuously. Also, since fuel is going through the motor brushes, wouldn't there be a spark there while the electric motor is spinning? Wouldn't that ignite the fuel? I don't know much about these things..."
most electric motors have a lubricant inside them, unfortunately gasoline acts as a solvent and washes off the lubricants. So the pumps are designed to use gasoline as a lubricant instead. Many fuel pump motors are quite powerful for their size, and run at 100% duty cycle (the run continuously) and will overheat without a constant flow of cool fuel. Most electric motors that run for extended periods with 100% duty cycle have some form of cooling. also keep in mind some electric motors are air cooled without a fan and may or may not use a heat sink to aid in cooling depending on how much heat they put out.
Liquid gasoline and diesel is non flammable. In fact assuming there is no vapors sitting on top of the fuel you can throw a lit match into a bucket of gasoline and it will put out the match. Gasoline VAPOR on the other hand is highly flammable when combined with oxygen. To burn 1 liter of VAPORIZED gasoline it needs to be mixed with approximately 15 liters of air to provide the requisite oxygen for complete combustion. For these reasons there is no concern of igniting the fuel from the spark caused by the electric fuel pump.
your fuel tank won't ignite just because of the sparking from pump rotor/stator. there's a lot of O2 in the gas tank (gas tanks usually have a bleed valve on the cap to let air in when fuel goes down). it's the ratio that does the magic. luquid fuel in a closed container hardly ever ignites. it's the fumes that do it, for one litre of gas you need 14.7 litre of air. theoretically there's only one sweetspot and that's when you're really empty. but you need VAPOR not liquid in order for it to expl