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#111
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Bill Putney wrote: > Ken Weitzel wrote: > >> >> Bill Putney wrote: >> >>> Ken Weitzel wrote: > > >>>> I do have one question though that I'd like to ask if >>>> I may? When I have a quarter tank of fuel left, what >>>> exactly occupies the remaining space? > > >>> If I see where you're going with this, the inside of the fuel pump >>> (where all the electrical commutation/sparking takes place) is 100% >>> full of liquid fuel under all conditions. Missing only one >>> ingredient for fire or explosion: air/oxygen. Comforting thought, eh? >>> >>> To answer your question: air (but all the arcing and sparking is >>> inside the pump with only liquid fuel). > > >> How about at the final few minutes of running out of >> fuel? > > > Pumping section (gerotor, turbine, or roller vane section as the case > may be for a given design) of the pump is below the commutation section. > Check valve in the fuel line keeping the pump full of fuel after pump > is shut off. There will always be a column of liquid fuel above the > pump commutation level. > >> How about turning on the ignition (running the pump >> for a few secs) when the tank is "empty" ? > > > See above. > >> How about a flaw in the diptube? > > > See above. It may be that no single-point of failure will cause a > problem. But, as with any system, you can hypothesize a **combination** > of failures that would creat a problem (cutting the odds) - you'd have > to argue whether or not such a combination of failures was credible. And > statistically, those combinations *will* happen. Don't ask me why there > haven't been real "unexplained" explosions. > >> I'm gonna respectfully suggest that were I given >> a choice; I'd take a pump in the engine compartment >> (the other side of the firewall being a nice side >> effect bonus) > > > Too much heat - fire and vapor lock potential in the modern engine > compartment. > > I hear you though. Do a google search on my name and > rec.autos.makers.chrysler and "commutation" and you'll see that I was > asking the same questions of Ford and Chrysler engineers when I was an > engineering manager for fuel pump products as a supplier - you'd be > surprised how many of them never even thought to ask the questions - > it's just the way things were done since before they were hired, so they > never thought about it. > > I often said it to them, and I said it in this ng, that if in-tank fuel > pumps had not been invented before now, and I thought of doing it, I, as > an engineer, never would have suggested it in today's legal and > corporate environment - I would have kept my mouth shut for career > protection. > > Actually, I seriously doubt that it would be being done now if it had > not had several years of being done with no indication that it was a > real problem. IOW - you could never prove, in theory, to a committe of > lawyers, managers, insurers, and MBA's that there could never be a > scenario that an explosion could not occur from some credible > combination of (1) running the tank out of fuel and (2) a bad in-line > check valve in the lines (allowing the liquid to drain back), and (3) > someone turning the ignition key to "run" and the fuel pump running dry > inside. Oh there will always be those who will have some explanation of > why it could never really explode - but wipe out their knowledge that it > has ever been done before and put them in the parallel universe where it > has not been done before and ask them to be the first person to > volunteer to sit in the first vehicle in which it was ever to be tried > the first time it was cranked up, and see if they will do it. Everyone > has great hindsight knowing that it is in reality apparently safe. But > to know ahead of time for sure...? Hi Bill... I'd have to be several kinds of fool to debate you given your experience. Perhaps though, we should together design a new system? I'm thinking of gravity... Ken |
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#112
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Bill Putney wrote: > Ken Weitzel wrote: > >> >> Bill Putney wrote: >> >>> Ken Weitzel wrote: > > >>>> I do have one question though that I'd like to ask if >>>> I may? When I have a quarter tank of fuel left, what >>>> exactly occupies the remaining space? > > >>> If I see where you're going with this, the inside of the fuel pump >>> (where all the electrical commutation/sparking takes place) is 100% >>> full of liquid fuel under all conditions. Missing only one >>> ingredient for fire or explosion: air/oxygen. Comforting thought, eh? >>> >>> To answer your question: air (but all the arcing and sparking is >>> inside the pump with only liquid fuel). > > >> How about at the final few minutes of running out of >> fuel? > > > Pumping section (gerotor, turbine, or roller vane section as the case > may be for a given design) of the pump is below the commutation section. > Check valve in the fuel line keeping the pump full of fuel after pump > is shut off. There will always be a column of liquid fuel above the > pump commutation level. > >> How about turning on the ignition (running the pump >> for a few secs) when the tank is "empty" ? > > > See above. > >> How about a flaw in the diptube? > > > See above. It may be that no single-point of failure will cause a > problem. But, as with any system, you can hypothesize a **combination** > of failures that would creat a problem (cutting the odds) - you'd have > to argue whether or not such a combination of failures was credible. And > statistically, those combinations *will* happen. Don't ask me why there > haven't been real "unexplained" explosions. > >> I'm gonna respectfully suggest that were I given >> a choice; I'd take a pump in the engine compartment >> (the other side of the firewall being a nice side >> effect bonus) > > > Too much heat - fire and vapor lock potential in the modern engine > compartment. > > I hear you though. Do a google search on my name and > rec.autos.makers.chrysler and "commutation" and you'll see that I was > asking the same questions of Ford and Chrysler engineers when I was an > engineering manager for fuel pump products as a supplier - you'd be > surprised how many of them never even thought to ask the questions - > it's just the way things were done since before they were hired, so they > never thought about it. > > I often said it to them, and I said it in this ng, that if in-tank fuel > pumps had not been invented before now, and I thought of doing it, I, as > an engineer, never would have suggested it in today's legal and > corporate environment - I would have kept my mouth shut for career > protection. > > Actually, I seriously doubt that it would be being done now if it had > not had several years of being done with no indication that it was a > real problem. IOW - you could never prove, in theory, to a committe of > lawyers, managers, insurers, and MBA's that there could never be a > scenario that an explosion could not occur from some credible > combination of (1) running the tank out of fuel and (2) a bad in-line > check valve in the lines (allowing the liquid to drain back), and (3) > someone turning the ignition key to "run" and the fuel pump running dry > inside. Oh there will always be those who will have some explanation of > why it could never really explode - but wipe out their knowledge that it > has ever been done before and put them in the parallel universe where it > has not been done before and ask them to be the first person to > volunteer to sit in the first vehicle in which it was ever to be tried > the first time it was cranked up, and see if they will do it. Everyone > has great hindsight knowing that it is in reality apparently safe. But > to know ahead of time for sure...? Hi Bill... I'd have to be several kinds of fool to debate you given your experience. Perhaps though, we should together design a new system? I'm thinking of gravity... Ken |
#113
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On Fri, 29 Oct 2004 23:00:03 +0200 (CEST), Nomen Nescio
> wrote: >Have you all observed that not one automobile has a drain valve installed >to the fuel tank? Obviously, a drain valve installed at the tank sump >would safely allow the complete drainage of a fuel tank before in-tank-fuel >pump or fuel gauge sending unit servicing. To the drain valve, a length of >hose would be attached and led to one or more 5 gallon Jerry cans. Once >drained, the fuel tanks are much safer to work on, although caution should >still be exercised. > >Attempting to drain a fuel tank by disconnecting the fuel outlet hose and >attaching a shop pump will drain all the usable fuel, but not all the fuel. >A gallon or more gasoline will be retained in the tank. > >Fuel tank drain valves have always been required on aircraft, but totally >ignored for cars. They are useful for draining water and or other >contaminants. I am sure that is a useful feature for mechanics trying to >efficiently diagnose or correct a refractory fuel system problem. > >There may be a few objections to a drain valve, but there are workarounds. >1. Makes it easy to steal fuel. 2. Vandalism and arson. 3. Accidental >collision damage to valve and resultant fuel leakage. 4. Leakage. 5. Cost >Workarounds are 1. build in key lock 2. build in key lock 3. Locate tank >higher than low point of nearby structures 4. install screw cap as per fuel >injection rail shraeder valve. 5. cost is a non-issue for safety, >particularly on $30,000 plus cars. > >A drainable fuel tank makes fuel pump servicing safer than presently; >however, an external pump design is still much safer yet. One reader >suggested that the mechanic wait until the fuel level is half or less -- >good luck if you fill your tank and 10 minutes later the pump quits. When >the pump quits, the engine stops right now! Now, if you had a DUAL fuel >pump system, you actually could run the fuel level down. I have addressed >this issue befo dual pumps, automatic controls, and warning indicators >when one fails. > >Think your car is advanced? There are four self-locking nuts on a Wal-Mart >shopping cart. They retain the casters. How many self-locking nuts are on >your $30,000 car. My car has none that I'm aware of. Car manufacturers >will do anything to avoid self lockers because of cost. Instead, auto >engineers did their own work-around for plain fasteners. They specify >torques at least 150% the maximum recommended by fastener torque tables. >Check it out. Every important fastener on your car is overtightened and >overstressed. > You are so full of $hit your eyes are brown. NO fasteners on a car are overtorqued by design. The bolts that carry high torque are SPECIFICALLY designed to stand that torque. As for fuel drains on fuel tanks, yes, aircraft have them. If a drop of water gets into the wrong place on an airplane you don't just pull over to the side of the road. You come down. That said, there are good reasons for NOT putting drain valves in automotive fuel tanks. When I started in the trade, they were common. Drain PLUGS, just like in an oil pan. Taking them out to drain fuel was more dangerous than pulling a line and letting it drain. The extra working of the metal, and welding in of the "boss" for the drain caused the tanks to rust out around the drain. On today's plastic tanks that would not be a problem, but in order for the drain to work as a drain it MUST be at the lowest point. Retention of the drain bolt in event of something being cought under the vehicle is a REAL issue, unlike the straw man you arer attempting to build around the in-tank pumps. The tanks must NOT LEAK under any cercumstances for environmental, as well as safety reasons. Also, it is ILLEGAL and UNSAFE to drain fuel into an open container. A proper, approved fuel drain unit is REQUIRED to safely drain a fuel tank. The fuel is drawn from the sealed tank, through an air-tight hose, into another sealed container that is GROUNDED to the vehicle being drained to avoid any chance of a static spark. Using this fuel drain unit, no fuel ever spills. As for the in-tank pump - the fuel acts as the coolant for the fuel pump. In some it is even the lubricant. The pump is always fully submurged in fuel - either liquid of vapour. Fuel vapour is significantly heavier than air, so even if air gets into the tank, the pump never sees it. The vapour pressure of Gasoline ensures the tank is virtually always air-free. The flamability limits of gasoline ensure it will NOT be lit by the "sparks" at the pump motor brushes. The electric fuel guage sender unit, basically an open rheostat, is MUCH more likely to cause a fire than the fuel pump - and has been in use since the late twenties. Never heard of a fire caused by the fuel guage. Externally mounted pumps, unless engine driven and engine mounted, are open to corrosion which can perforate the pump case, allowing it to leak fuel. The connections are also open to corrosion - and they are exposed to air, which contains oxygen, which gasoline requires inorder to burn.. Also, fuel pumps are MUCH better at pushing fuel than sucking it, and fuel vapourizes at a lower temperature when under low pressure - so vapour lock is ALWAYS a possibility with front mounted pumps - while almost unheard of with intank "pusher" pumps. With fuel injection, an engine driven pump poses a problem - how do you get fuel to the engine to start the engine, when the pump is driven by the engine? Yes, it was done with the diaphragm pumps running at roughly 5PSI for carbs - but with EFI it is not so simple. Go with mechanical FI instead?? Sure - with all the serious problems that go with that setup. You could not afford to own one - particularly if it had to meet emission standards. I have worked on vehicles with vacuum operated fuel pumps - firewall mounted and gravity feeding to the carb, engine driven mechanical pumps, frame mounted electric pumps, both rotary centrigugal, rotary vane, rotary "roller cell" and plunger/diaphragm motor driven (AC) and solenoid driven (SU), and i n-tank electric pumps, both centrifugal and roller element and vane types. By FAR the most trouble free have been the in-tank roller element and vane pumps. I have seen MANY of them go over 300,000 miles without a single problem. I have seen them last 20 years without a problem. Up here in the salt belt a frame mounted pump of any description is doing well to last 10 years or 90,000 miles. Engine driven diaphragm pumps - even with the old leaded gasoline, did good to go 10 years. 5 was a lot more common. With today's ethanol blended and oxygenated fuels they would not last much more than half as long.. I have yet to hear of a vehicle fire caused by an intank pump. I have seen several fires caused by half-wits spilling gasoline while attempting to remove or drain a fuel tank - with or without intank pump, and either lighting a torch to snip off a stubborn tank strap bolt, or thoughlessly lighting up a smoke a few feet away. Or dropping an incandescent trouble light, or spilling gas on one. Ive seen fires caused by gasoline vapour, spilling over the top of an open pail of gasoline and settling in the open drain of the shop, being ignited by a chance spark from either welding, cutting, grinding, dropping a tool, a dropped match or cig butt, etc. I've seen fires caused by short circuits while working on a vehicle electrical system without disconnecting the battery ground - and even from some dim-wit trying to remove the battery power lead instead of the ground, and shorting the power to ground, blowing up the battery. But NEVER from an intank fuel pump failure. And I've been in the business a long time - and worked on vehicles from the early twenties to the 2000s. |
#114
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On Fri, 29 Oct 2004 23:00:03 +0200 (CEST), Nomen Nescio
> wrote: >Have you all observed that not one automobile has a drain valve installed >to the fuel tank? Obviously, a drain valve installed at the tank sump >would safely allow the complete drainage of a fuel tank before in-tank-fuel >pump or fuel gauge sending unit servicing. To the drain valve, a length of >hose would be attached and led to one or more 5 gallon Jerry cans. Once >drained, the fuel tanks are much safer to work on, although caution should >still be exercised. > >Attempting to drain a fuel tank by disconnecting the fuel outlet hose and >attaching a shop pump will drain all the usable fuel, but not all the fuel. >A gallon or more gasoline will be retained in the tank. > >Fuel tank drain valves have always been required on aircraft, but totally >ignored for cars. They are useful for draining water and or other >contaminants. I am sure that is a useful feature for mechanics trying to >efficiently diagnose or correct a refractory fuel system problem. > >There may be a few objections to a drain valve, but there are workarounds. >1. Makes it easy to steal fuel. 2. Vandalism and arson. 3. Accidental >collision damage to valve and resultant fuel leakage. 4. Leakage. 5. Cost >Workarounds are 1. build in key lock 2. build in key lock 3. Locate tank >higher than low point of nearby structures 4. install screw cap as per fuel >injection rail shraeder valve. 5. cost is a non-issue for safety, >particularly on $30,000 plus cars. > >A drainable fuel tank makes fuel pump servicing safer than presently; >however, an external pump design is still much safer yet. One reader >suggested that the mechanic wait until the fuel level is half or less -- >good luck if you fill your tank and 10 minutes later the pump quits. When >the pump quits, the engine stops right now! Now, if you had a DUAL fuel >pump system, you actually could run the fuel level down. I have addressed >this issue befo dual pumps, automatic controls, and warning indicators >when one fails. > >Think your car is advanced? There are four self-locking nuts on a Wal-Mart >shopping cart. They retain the casters. How many self-locking nuts are on >your $30,000 car. My car has none that I'm aware of. Car manufacturers >will do anything to avoid self lockers because of cost. Instead, auto >engineers did their own work-around for plain fasteners. They specify >torques at least 150% the maximum recommended by fastener torque tables. >Check it out. Every important fastener on your car is overtightened and >overstressed. > You are so full of $hit your eyes are brown. NO fasteners on a car are overtorqued by design. The bolts that carry high torque are SPECIFICALLY designed to stand that torque. As for fuel drains on fuel tanks, yes, aircraft have them. If a drop of water gets into the wrong place on an airplane you don't just pull over to the side of the road. You come down. That said, there are good reasons for NOT putting drain valves in automotive fuel tanks. When I started in the trade, they were common. Drain PLUGS, just like in an oil pan. Taking them out to drain fuel was more dangerous than pulling a line and letting it drain. The extra working of the metal, and welding in of the "boss" for the drain caused the tanks to rust out around the drain. On today's plastic tanks that would not be a problem, but in order for the drain to work as a drain it MUST be at the lowest point. Retention of the drain bolt in event of something being cought under the vehicle is a REAL issue, unlike the straw man you arer attempting to build around the in-tank pumps. The tanks must NOT LEAK under any cercumstances for environmental, as well as safety reasons. Also, it is ILLEGAL and UNSAFE to drain fuel into an open container. A proper, approved fuel drain unit is REQUIRED to safely drain a fuel tank. The fuel is drawn from the sealed tank, through an air-tight hose, into another sealed container that is GROUNDED to the vehicle being drained to avoid any chance of a static spark. Using this fuel drain unit, no fuel ever spills. As for the in-tank pump - the fuel acts as the coolant for the fuel pump. In some it is even the lubricant. The pump is always fully submurged in fuel - either liquid of vapour. Fuel vapour is significantly heavier than air, so even if air gets into the tank, the pump never sees it. The vapour pressure of Gasoline ensures the tank is virtually always air-free. The flamability limits of gasoline ensure it will NOT be lit by the "sparks" at the pump motor brushes. The electric fuel guage sender unit, basically an open rheostat, is MUCH more likely to cause a fire than the fuel pump - and has been in use since the late twenties. Never heard of a fire caused by the fuel guage. Externally mounted pumps, unless engine driven and engine mounted, are open to corrosion which can perforate the pump case, allowing it to leak fuel. The connections are also open to corrosion - and they are exposed to air, which contains oxygen, which gasoline requires inorder to burn.. Also, fuel pumps are MUCH better at pushing fuel than sucking it, and fuel vapourizes at a lower temperature when under low pressure - so vapour lock is ALWAYS a possibility with front mounted pumps - while almost unheard of with intank "pusher" pumps. With fuel injection, an engine driven pump poses a problem - how do you get fuel to the engine to start the engine, when the pump is driven by the engine? Yes, it was done with the diaphragm pumps running at roughly 5PSI for carbs - but with EFI it is not so simple. Go with mechanical FI instead?? Sure - with all the serious problems that go with that setup. You could not afford to own one - particularly if it had to meet emission standards. I have worked on vehicles with vacuum operated fuel pumps - firewall mounted and gravity feeding to the carb, engine driven mechanical pumps, frame mounted electric pumps, both rotary centrigugal, rotary vane, rotary "roller cell" and plunger/diaphragm motor driven (AC) and solenoid driven (SU), and i n-tank electric pumps, both centrifugal and roller element and vane types. By FAR the most trouble free have been the in-tank roller element and vane pumps. I have seen MANY of them go over 300,000 miles without a single problem. I have seen them last 20 years without a problem. Up here in the salt belt a frame mounted pump of any description is doing well to last 10 years or 90,000 miles. Engine driven diaphragm pumps - even with the old leaded gasoline, did good to go 10 years. 5 was a lot more common. With today's ethanol blended and oxygenated fuels they would not last much more than half as long.. I have yet to hear of a vehicle fire caused by an intank pump. I have seen several fires caused by half-wits spilling gasoline while attempting to remove or drain a fuel tank - with or without intank pump, and either lighting a torch to snip off a stubborn tank strap bolt, or thoughlessly lighting up a smoke a few feet away. Or dropping an incandescent trouble light, or spilling gas on one. Ive seen fires caused by gasoline vapour, spilling over the top of an open pail of gasoline and settling in the open drain of the shop, being ignited by a chance spark from either welding, cutting, grinding, dropping a tool, a dropped match or cig butt, etc. I've seen fires caused by short circuits while working on a vehicle electrical system without disconnecting the battery ground - and even from some dim-wit trying to remove the battery power lead instead of the ground, and shorting the power to ground, blowing up the battery. But NEVER from an intank fuel pump failure. And I've been in the business a long time - and worked on vehicles from the early twenties to the 2000s. |
#115
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On Fri, 29 Oct 2004 22:54:06 -0400, "Al Smith" >
wrote: >Wait a minute. Maybe there are shortcuts in some cases - and I have only >done >it once - but every fuel pump replacement I have heard about >involves dropping the tank. > None of the intank fuel pumps used on carbureted Toyota vehicles required removal of the tank to replace. All had screwed on access covers either in the trunk or floor under the rear seat to access the fuel sender.fuel pickup/fuel pump.. Many other vehicles were built the same. Many of today's vehicles DO require dropping the tank - and MANY of those tanks are plastic, not steel.. Many of them have quick disconnects to disconnect the fuel lines, and if less than 1/4 full pose a very limitted danger of spillage when removing. They are also usually relatively simple to drain with a proper fuel transfer pump, either electrical, air powered, or manual. Most fuel injected vehicles can be easily drained from under the hood by connecting the transfer pump to the service valve on the fuel rail - without getting ANY fuel or fuel vapours into the shop, and with NO danger of fire. >e. g. >http://popularmechanics.com/automoti...place_intank_f >uel_pump/ > >There is no way dropping the tank can be compared to disconnecting >two fuel lines and unplugging the electric plug. > >And as >> far as "reality"....the trained tech has already taken his lumps on >> the warranty side of things (low times) and has become extremely >> efficient at doing the job by the time it becomes a "customer pay" >> job. Who are you to pass judgement on them.....come and walk >> in their shoes for a mile or two and then you will know what >> flat rate is all about. >> >> > In their defence, shops use book time out of necessity sometimes, >> > because of a lack of local knowledge. In their attack, shops and >> > techs use book time to make money on flat-rate labour. Techs and >> > shops alike continually look for common, high-book-time gems with >> > which to bilk their customers and reap profits. >> >> This may be true in a certain percentage of labour operations, >> but most operations, "you" as the owner, could not come close >> to doing it in the time allowed by the book. You might be able >> to beat the time on a thermostat, but if you were working on vehicles >> all day long, you'd lose your ass. I'd extend a challenge to anyone >> who isn't a professional technician to come on in and work with me >> for a week. It'll be an eye opener both ways....you will see the jobs >> that I make tons of time on, and you will see the jobs that waste my >> time. It usually works out to about 140% efficiency overall. And you >> would learn why I'm worth that. >> >> > The saddest and most uncertain factor in these equations is the newbie >> > tech who just invested $50,000 in his or her education and tools to >> > work on new cars. >> >> Good god....whoever spends that kind of money to get started in this >> trade is a lunatic. Or has some sort of "tool fetish". I've seen those >> types >> of technicians. Lot's of shiny tools, but have no clue what to do with >> them. >> >> > Too many fail or quit, and most are underpaid for >> > their valuable work. Others succeed, and either become vampires >> > themselves, or are good enough (morally and skill-wise) to turn an >> > honest, good profit and NOT screw consumers with (on average) 100% >> > markups on parts and book-billed labour. >> >> Too many fail or quit, because they imagine that they can be making >> 80 grand in five years. It doesn't work that way....it takes a lot of >> time and experience to become a good, honest, flat rate mechanic. >> I laugh at the young guys in our shop that think they should be making >> 14 hrs a day. It certainly won't happen if they take an hour in the >morning >> to "get going"...and spend another hour or two a day outside smoking and >> bull****ting with everyone. You gotta work hard in this trade if you want >> to make good money. And you "can" make good money. >> >> Ian >> >> > |
#116
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On Fri, 29 Oct 2004 22:54:06 -0400, "Al Smith" >
wrote: >Wait a minute. Maybe there are shortcuts in some cases - and I have only >done >it once - but every fuel pump replacement I have heard about >involves dropping the tank. > None of the intank fuel pumps used on carbureted Toyota vehicles required removal of the tank to replace. All had screwed on access covers either in the trunk or floor under the rear seat to access the fuel sender.fuel pickup/fuel pump.. Many other vehicles were built the same. Many of today's vehicles DO require dropping the tank - and MANY of those tanks are plastic, not steel.. Many of them have quick disconnects to disconnect the fuel lines, and if less than 1/4 full pose a very limitted danger of spillage when removing. They are also usually relatively simple to drain with a proper fuel transfer pump, either electrical, air powered, or manual. Most fuel injected vehicles can be easily drained from under the hood by connecting the transfer pump to the service valve on the fuel rail - without getting ANY fuel or fuel vapours into the shop, and with NO danger of fire. >e. g. >http://popularmechanics.com/automoti...place_intank_f >uel_pump/ > >There is no way dropping the tank can be compared to disconnecting >two fuel lines and unplugging the electric plug. > >And as >> far as "reality"....the trained tech has already taken his lumps on >> the warranty side of things (low times) and has become extremely >> efficient at doing the job by the time it becomes a "customer pay" >> job. Who are you to pass judgement on them.....come and walk >> in their shoes for a mile or two and then you will know what >> flat rate is all about. >> >> > In their defence, shops use book time out of necessity sometimes, >> > because of a lack of local knowledge. In their attack, shops and >> > techs use book time to make money on flat-rate labour. Techs and >> > shops alike continually look for common, high-book-time gems with >> > which to bilk their customers and reap profits. >> >> This may be true in a certain percentage of labour operations, >> but most operations, "you" as the owner, could not come close >> to doing it in the time allowed by the book. You might be able >> to beat the time on a thermostat, but if you were working on vehicles >> all day long, you'd lose your ass. I'd extend a challenge to anyone >> who isn't a professional technician to come on in and work with me >> for a week. It'll be an eye opener both ways....you will see the jobs >> that I make tons of time on, and you will see the jobs that waste my >> time. It usually works out to about 140% efficiency overall. And you >> would learn why I'm worth that. >> >> > The saddest and most uncertain factor in these equations is the newbie >> > tech who just invested $50,000 in his or her education and tools to >> > work on new cars. >> >> Good god....whoever spends that kind of money to get started in this >> trade is a lunatic. Or has some sort of "tool fetish". I've seen those >> types >> of technicians. Lot's of shiny tools, but have no clue what to do with >> them. >> >> > Too many fail or quit, and most are underpaid for >> > their valuable work. Others succeed, and either become vampires >> > themselves, or are good enough (morally and skill-wise) to turn an >> > honest, good profit and NOT screw consumers with (on average) 100% >> > markups on parts and book-billed labour. >> >> Too many fail or quit, because they imagine that they can be making >> 80 grand in five years. It doesn't work that way....it takes a lot of >> time and experience to become a good, honest, flat rate mechanic. >> I laugh at the young guys in our shop that think they should be making >> 14 hrs a day. It certainly won't happen if they take an hour in the >morning >> to "get going"...and spend another hour or two a day outside smoking and >> bull****ting with everyone. You gotta work hard in this trade if you want >> to make good money. And you "can" make good money. >> >> Ian >> >> > |
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> wrote in message ... > On Fri, 29 Oct 2004 22:54:06 -0400, "Al Smith" > > wrote: > > >Wait a minute. Maybe there are shortcuts in some cases - and I have only > >done > >it once - but every fuel pump replacement I have heard about > >involves dropping the tank. > > > > None of the intank fuel pumps used on carbureted Toyota vehicles > required removal of the tank to replace. All had screwed on access > covers either in the trunk or floor under the rear seat to access the > fuel sender.fuel pickup/fuel pump.. Many other vehicles were built the > same. > > Many of today's vehicles DO require dropping the tank - and MANY of > those tanks are plastic, not steel.. Many of them have quick > disconnects to disconnect the fuel lines, and if less than 1/4 full > pose a very limitted danger of spillage when removing. They are also > usually relatively simple to drain with a proper fuel transfer pump, > either electrical, air powered, or manual. > > Most fuel injected vehicles can be easily drained from under the hood > by connecting the transfer pump to the service valve on the fuel rail > - without getting ANY fuel or fuel vapours into the shop, and with NO > danger of fire. If you have about a week to wait for the fuel to tranfer........ <snip> |
#118
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> wrote in message ... > On Fri, 29 Oct 2004 22:54:06 -0400, "Al Smith" > > wrote: > > >Wait a minute. Maybe there are shortcuts in some cases - and I have only > >done > >it once - but every fuel pump replacement I have heard about > >involves dropping the tank. > > > > None of the intank fuel pumps used on carbureted Toyota vehicles > required removal of the tank to replace. All had screwed on access > covers either in the trunk or floor under the rear seat to access the > fuel sender.fuel pickup/fuel pump.. Many other vehicles were built the > same. > > Many of today's vehicles DO require dropping the tank - and MANY of > those tanks are plastic, not steel.. Many of them have quick > disconnects to disconnect the fuel lines, and if less than 1/4 full > pose a very limitted danger of spillage when removing. They are also > usually relatively simple to drain with a proper fuel transfer pump, > either electrical, air powered, or manual. > > Most fuel injected vehicles can be easily drained from under the hood > by connecting the transfer pump to the service valve on the fuel rail > - without getting ANY fuel or fuel vapours into the shop, and with NO > danger of fire. If you have about a week to wait for the fuel to tranfer........ <snip> |
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