98 fuel pump ?

rcweston · 05-07-2008, 08:19 PM

98 Lumina 3.8 just wouldn't start today. Never done this before. Checked spark, it's ok but fuel pump doesn't seem to operate. Checked fuel pump relay and all is good. Metered resistance (OHMS) from relay to pump. 275 Ohms. seems high to me but I don't really know what it should be. also checked at connector next to gas tank. I done have a great schematic but I'm quite sure the gray and black leads are the pump leads. I would expect just a few ohms in the pump motor. Does anyone out there know.
If the pump motor has gone bad, is their any info that would help in replacing it.
Thanks Rex

DnaProRacing · 05-07-2008, 09:07 PM

when my pump went bad. the only thing we really had an issue with was putting the tank back on. the straps faught us hard. but once we got them lined up, done deal. rather easy. you will need help for sure, need someone to hold the tank up while you try to get the straps started on the bolts. we ended up using a jack to help hold it up. it took a while.
as for the amperage, thats beyond my knowledge. one of the mods here can answer that for ya...

Will Help · 05-07-2008, 09:12 PM

I suggest dropping the tank and cleaning out 10 years worth of crud while changing the pump. Just remember that gas weighs about 8 pounds a gallon. ( 10 gallons is 80 extra pounds you have to handle). Just play safely if you have to drain the tank.

Some people will tell you to cut a hole in the floor pan if it is not already equipped with an access hole.

Blue Bowtie · 05-07-2008, 11:59 PM

Yes, about 7.5-10 ohms would be about right.

rcweston · 05-08-2008, 02:41 PM

from your posts, I see the pump looks bad. I have tried all morning to get the gas out of the tank with no success. (it's completely full) using a siphon isn't working. can't get it past the filler entrance of the tank nor the entrance through the smaller breather/evaporative line. Are their any suggestions out there?

Will Help · 05-08-2008, 06:50 PM

May have to disconnect the line at fuel filter and connect a line from the filter to your cantainers and try to syphon through the line.

rcweston · 05-08-2008, 06:56 PM

Thanks for the further info. After a couple of hours and 11 1/2 gallons later, I think the tank is about empty!
thanks Rcweston

Will Help · 05-09-2008, 03:30 PM

Anytime. That is what we are here for. Sometimes they think we are crazy, but thats what they thought of the Wright Brothers!!!

rcweston · 05-13-2008, 04:47 PM

Problem corrected! Thanks everyone for the help..
Just though I would share what I found in replacing this pump in case some others might have the same trouble.
It was difficult getting the gas out of a completely full tank. You can't just put a siphon down the filler tube. It has a baffle in the tank that stops it from entering far enough to do any good. Take the filler connection apart and undo all supports for the filler and breather tube in the wheel well. Then remove the clamps that connect the two tubes to the tank. If the tank is full, you have to have the car slanted forward to keep the gas from just coming out. I had to lift the rear end over a foot and a half. Lifting also gave me plenty of room to work under the card. a small siphon can now be placed into the breather tube from under the cars and forced into the tank. Now the gas can be removed. 13 1/2 gallons
The only other hard part was getting the "duck bill" tube connections apart. You have to undo the tank straps to let the tank slide forward enough to be able to disconnect the rear duckbills(the forward ones are easily accessed). Using a disconnect tool really helped.
After the tank is off, undo the spring ring and the module will slide right out. At this point you can replace the entire sending module/gas pump for about $300-$350 or you can purchase a replacement pump only for about $70. (http://www.efuelpumps.com/) Ordered on Saturday, received on Monday!! If you purchased the pump only, you will need to take the pump and two hoses out of the module and replace them. Getting the old parts out was difficult at best. The old lines had to be cut off down 4 inches inside of the module were they connect. (very difficult!!) I used a dremell rotary tool with a tiny 1/4 inch saw blade to reach that far down and was very careful to only cut as deep as the thickness of the tubes (every thing is plastic). Their is probably a better way but that is what worked for me. clean this up immaculately. you don't want any partials to get in you injectors. Putting it back together was much easier. I heated the tubes a little and the slide on nicely. Clamps were provided to secure their fit.
Replace the module back in the tank and the tank back in the car , connect all tubing and wiring. Connect the filler tubes and your back in business.
One last bit of info. The new pump measured 39 ohms of resistance on the meter. The old (bad pump) measured over 275 ohms in one spot only(too much resistance to start the pump spinning from a stop. The old pump ended up having a dead spot on it's windings.
Thanks again to everyone.
Rex

DnaProRacing · 05-13-2008, 09:33 PM

wow, i didnt have that much trouble doing that. we backed the car up onto ramps, released the straps, guided the tank to the ground, then two of us drained the tank into pickle buckets. like i mentioned before, the only issue was putting the tank back on cuz the straps faught us hard. all in all, it took just shy of an hour to do it all...
glad you got it fixed. nothing feels better than repairing it yourself...

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