Trouble is, these pumps run immersed in fuel. They are DC brush motors and depending upon how much micro contaminants (abrasives) come with the fuel, the brushes mill the commutator away until there is no metal left to conduct electricity. Toward the end they sometimes become temperture sensitive and as one person noted, jarring them will often seat the brushes and get them going again for a short while. Average life is @ 100-150K.
The big problem is accesibility for replacement. Could the pumps be improved? Yes. Will they? Probably not.
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"Not all who are lost are wondering" say Bill & Heidi
'78 Excella 500,"The Silver Pullit". vacuum over hydraulic disc brakes, center bath, rear twin. '67 Travelall 1200 B 4X4 WBCCI 3737
Last edited by Excella CM; 06-27-2007 at 12:44 PM..
wow.... that's some SERIOUS wear going on there! I don't know... something about metal on metal wear, electricity, and a bath of fuel......
WHAT about this situation seems wrong...
I know it's supposed to go 100,000K miles or more, but evidence here and that that I know personally tells me this isn't so.
Do Dodge and Ford do the same thing? I better knock on wood, as my Dodge (a 94) is still running strong. I know Chev Astro's have the same problem with their pumps too.
Marc
Diagnostic check ($80/hr) found a blown fuse to the ECM... "Over amperage".... Will have to check my "Haynes manual" to find location, wattage and the like.... for the next time...
Now, I do live out past the sticks so I do have some fairly high wattage fog/driving lights on the truck.... but they were off in town, during daylight hours.... TV was running AOK - as normal - when on the way to town.... Also recently added the electric fan (also OFF) to aid cooling of the tranny cooler. Then there was the 2 small DVD screens running off 12V.... however, both front and rear A/C's were going.... but that should be well inside the parameters for normal usage....?! Nothing is really tripping swithches here as far as obvious draws that might cause this fuse to blow... Anyone else see things differently?
Comment about the fuel gauge registering incorrectly, prior to pump failure, was interesting, as my gauge reads full all the time, then drops slowly but never to less than 1/2, even with only 2 or 3 gallons on board.... as per pump receipts compared to tank specs. Is this the 'indicator' you referenced about a possible pump failure coming? There are NO other indicators (stumbling, etc....) that the vehicle exhibits.
More info please... the 'actual' expereinces are also very illuminating.
Brakes are being redone as I type this ie rotors resurfaced - 2 hrs labor for that.... then pads & the like. They mentioned a 'brake flush' being needed - every 80-100K. Something about brake fluid being 'hydro-static' (attracting water thru the seals & hoses) What say you? My owners manual/ maintenance log is with the car.... Seems so logical, but I'll have their bu**s if its snakeoil....
I have always heard that it is a good idea to flush your brake system periodically. Brake fluid does absorb water and it settles in the calipers. I can't guarantee that this is all true but I do know that the brake fluid does get very dirty and I feel much better having it flushed every 100K or so.
Brake fluid is hydrophilic-loves water. It absorbs water, mainly out of the air. This water is available to corrode the shiny steel and aluminum surfaces in the master and slave and wheel cylinders. It can also boil when brakes get hot causing a soft pedal. It is good, economical practice to change out(by flushing) the brake fluid every two years. Much cheaper in the long run. Calipers tend to be less prone to damage and leaks caused by water contamination. The master cylinder is usually the first to go. The much more complex and costly ABS systems can really benefit from the protection of regular fluid changes.
__________________
"Not all who are lost are wondering" say Bill & Heidi
'78 Excella 500,"The Silver Pullit". vacuum over hydraulic disc brakes, center bath, rear twin. '67 Travelall 1200 B 4X4 WBCCI 3737
Comment about the fuel gauge registering incorrectly, prior to pump failure, was interesting, as my gauge reads full all the time, then drops slowly but never to less than 1/2, even with only 2 or 3 gallons on board.... as per pump receipts compared to tank specs. Is this the 'indicator' you referenced about a possible pump failure coming? There are NO other indicators (stumbling, etc....) that the vehicle exhibits.
They mentioned a 'brake flush' being needed - every 80-100K. Something about brake fluid being 'hydro-static' (attracting water thru the seals & hoses) What say you? My owners manual/ maintenance log is with the car.... Seems so logical, but I'll have their bu**s if its snakeoil....
Thanks for the help and replies so far.....
Axel
SilverToy
Fuel gauge reading incorrectly is usually only an indication of a bad sending unit, you can get a new one with a pump. It doesn't mean the pump is going bad. "Stumbling" could be seen as loping while idling, or the occasional sputter while driving.
Here in humid Florida, we recommend flushing the brake fluid every 3 years due to the higher moisture in the air. Brake fluid does attract water, as it has an alcohol base. The second reason for flushing is to get rid of the tiny particles of rubber and metal suspended in the fluid. If there is enough of this stuff floating around in the system, it can cause other issues.
As always, the info offered here is terrific, and a great help in knowing that my vehicle is in good hands. Always thought they were good folks, doing the right things for the right reasons (in addition to getting paid) and glad to see that proven out. Thanks.
Brakes are done. Starting issue/ fusable link done. Test drive - CRAP. Pulling all over the place. Back on the rack. Right tie rod bent about 1/2 inch - Toe in. Now it needs a new tie rod, alignment... and the $'s keep on rollin along...
Thinking back, 2 drivers in the Flatbed. ?? One guy is in training. Guess which corner (He did 1 of 4) he hooked up!? Called the tow company right away. Also called USAA, who arranged the tow. They took a damage claim.... week to 10 days for an answer....
Outta the frying pan and into the fire..... If it weren't for bad luck I'd have no luck at all....
2001 Denali needed new fuel pump at 125k. It did give us warning that it was failing. During cold startup the RPM would drop and required pumping the gas pedal until warm. Replaced at a non GM shop but it still HURT!
Brakes are done. Starting issue/ fusable link done. Test drive - CRAP. Pulling all over the place. Back on the rack. Right tie rod bent about 1/2 inch - Toe in. Now it needs a new tie rod, alignment... and the $'s keep on rollin along...
Thinking back, 2 drivers in the Flatbed. ?? One guy is in training. Guess which corner (He did 1 of 4) he hooked up!? Called the tow company right away. Also called USAA, who arranged the tow. They took a damage claim.... week to 10 days for an answer....
Sigh.
Axel
SilverToy
Hooking to the tie rod is a typical newbie wrecker drive mistake. I never made that particular mistake when I was learning, but I did tear the outer cv boot on a 1967 Toronado, the first front wheel drive car I had seen.
The older cars and truck with gutsy engines has trouble with vaporlock when using the newer fuels. That problem was fixed by installing an external electric fuel pump back at the tank. Now the new vehicles put the pumps in the tank as noted but you can still get these external pumps that perform well. Would this be a resonable solution?
The older cars and truck with gutsy engines has trouble with vaporlock when using the newer fuels. That problem was fixed by installing an external electric fuel pump back at the tank. Now the new vehicles put the pumps in the tank as noted but you can still get these external pumps that perform well. Would this be a resonable solution?
My truck has both, one in each tank, and one mounted on the frame rail. The tank mounted ones are low pressure, the frame mounted on is high pressure.
Volvo used to have a low pressure pump in the tank and the high pressure pump to feed the injectors was under the car. You removed a small access plate to replace the low pressure and you could reach the high pressure underneath...but did not have to remove the fuel tank for either! Kinda like they were thinking of ease of servicing. I wonder where it is for my f350 duel tank diesel?
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Catmando
"There’s not much in life we can’t over-analyze”