In tank electric fuel pumps??

[partsman]

Now, it has been pouring rain here, so with truck down and sitting outside I can't really do much for now, I had to focus my attention on my 97 Taurus so I can have transportation till I get the truck fixed.
Anyway I tried at least to test from #85 to #86 on relay and got continuity, can't really say I can here of feel it click when key on as other relays seem to kick in also, and there does not appear to be another relay like mine to swap out.
Anyway tried to look for this pump bypass that someone mentioned should be around the fuse and relay block but not seeing what looks like anything I can use to bypass to the pump.
Not sure on how to tell what colour wires are to jumper across like someone said once I remove the relay, don't want to blow anything, been told to make a fused jumper wire, guess I could buy a fuse holder and attach clips or whatever to it and try and find where to jumper from to put I gather full power to pump, wish I could find some good pictures of what to look for or some good schematics that might help.
Have been told it may be the connection at the tank too, so how hard is that to get to?
Pouring rain here and the ground is good and muddy now, so unless it dries up soon it could be a while till I can crawl under or even try to work under the hood.
Appreciate the info so far, all help welcomed, as I have been told I do not want to drop the tank and find out the pump was okay.
It is too bad I had to install the fifth wheel hitch, as it would be a pain to get in to remove it to be able to lift box, will be stuck with dropping the tank.

[BernieB]

A word of advice... Siphon the tank empty before you drop it. Much easier and safer that way, even if you have to buy a couple of cans.

[partsman]

Thanks, I had just filled it the day before it quit.
So she is 128 litres of fuel.
A might heavy.

[partsman]

I forgot to ask, I have been told to not just replace pump in tank, but buy the whole hanger and harness and all other related parts, supposed to be better as then you have the sender new and the harness has been a problem that GM knew about.

[bubbatrucklover]

Originally Posted by bradrhale

i hate to be the bearer of bad news, but stumppuller had to take a small vacation away from this place. he promises to be back but do to items unrelated to the forum, he will be away for a little while.

That's too bad but I FULLY understand when "real life" takes place over fun like hanging out and learning/sharing here.

[BernieB]

Originally Posted by partsman

Thanks, I had just filled it the day before it quit.
So she is 128 litres of fuel.
A might heavy.

Almost 100kg, not counting the weight of the tank itself. And yes, if you can afford it, but the whole shebang... pump, harness, sender, etc. Because, sure as Ford made black Model T's, if you don't change it then a week or a month from now it's gonna go.

[crabtruck]

Originally Posted by partsman

... I tried at least to test from #85 to #86 on relay and got continuity,
can't really say I can here of feel it click when key on as other relays seem to kick in
, ...Anyway tried to look for this pump bypass that someone mentioned should be
around the fuse and relay block but not seeing what looks like anything I can use to bypass to the pump.
Not sure on how to tell what colour wires are to jumper across like someone said
once I remove the relay, don't want to blow anything,
been told to make a fused jumper wire, guess I could buy a fuse holder and attach clips
to it and try and find where to jumper from to put I gather full power to pump,
wish I could find some good pictures of what to look for or some good schematics that might help.
Have been told it may be the connection at the tank too, so how hard is that to get to?
Pouring rain here ....be a while till I can crawl under or even try to work under the hood....

Always knew one day I'd be someone.

Read all the way through before doing anything,
you may find a different point of attack, and it'll make more sense.

1)
Alright let me give you an indoor project for this:
Need 9v battery, some clips to connect it to relay, clips for meter to relay.

2)
Basics: 86(+) to 85(-) = coil, 30(or51) = out, 87a = off choice, 87 = on choice.
In other words 30/51 connects to 87a with no power, 30/51 to 87 with power.
This 5-wire relay acts like a "chooser" of 87 or 87a, not like solenoid's on/off.
85&86 never connect to 30,87,or 87a. 87 never connects to 87a.

3)
Take the relay in house. Re-ohm 85-86 (control coil) to be roughly 40-80 ohms.
Use some clips so meter stays put, and ohm 30-87. Should be open / infinity.
Leave meter hooked.
Touch battery to relay ---> 85 = (-) and 86 = (+). .....correct polarity !!
Relay may "click" but what you need is meter at 30-87 goes short / zero .
What is happening here: 9v is doing the ECM's job of turning on pump

4)
If this part works you don't really need to other "side" of relay to work
since it is for shops to use with the "fuel pump prime" connector.
If you wanted to check, 30-87 acts opposite to 30-87a.
We'll just do life simple and go around that.

5)
Put away 9v and see if rain stopped.
Make a fused jumper with solid 14 or 16 gauge wire.
Solid helps avoid shorts when you use ends of wire as probes.
Use a 15A or smaller fuse so ECM fuse does not blow first.
Strip ends of jumper wire 1/8", too long makes easy shorts.

6)
Colors for reference, may not need to know to get this done.
85=Blk/Wht, 86=DkGrn/Wht, 30/51=Gry, 87=Org, 87a=Red.
Only said for this truck, others vary.

7)
Look, careful not to let "upside down" fool you, where 30 and 87 are located
in the relay socket. (Relay stays out for this proceedure.)
Confirm you are right about location of 87 by measuring 12v there when key is on.
87 in that socket is hot from ECM-B fuse#L8.
You may also have 5-12v on 86 from ECM, and this is BAD place for jumper.

8)
Turn key off and have jumper ready.
You / helper turn key on and wait for truck to be quiet (other servos may make noise)
Use the jumper from 30 to 87 in the socket. Should hear pump run.
With full tank may need to be very close to hear.

9)
If pumps does not run, then you have two possibilities: wires or pump.
If pump, then you know what's needed so lets talk wire.

10)
"Hot" comes from relay 30 on a Gray wire to pump.
On the way, it is spliced with another Gray wire from the oil pressure sensor.
The oil press sensor has three wires: that Gray, an Org that goes back to same ECM-B fuse,
and a third wire for pressure gauge.
You want to inspect for breaks, corrosion, etc along that route from relay to tank.
You are not looking for shorts since that would have blown fuse.
Pay particular attention to the splice to be clean and tight.

11)
"Ground" comes from pump on Blk/Wht wire and is a typical candidate for failure.
This ground is shared with fuel gauge though, so if gauge is good, probably ok.
Poor connection can cause problems, so do inspect anyways.

12)
At the tank is a plug connector for pump and sender.
Check this also for tightness and signs of corrosion.

13)
This is all your own fault, you started by asking if pump could fail, then it did.
Seriously though, it seems as if your troubles started after 5th whl installation,
which is right there in the neighborhood.
I would start by looking for wires/connections you "stretched" while installing.

It could be pump, but no pump is good without juice.
Congratulations, you read the whole thing.

[partsman]

Wow!
Thanks, that is great, this will be very valuable.

[Chevy_Finatic79]

whack the tank with a nice size 2x4 it should make the pump work temporarily

[hotrodpc]

Originally Posted by Chevy_Finatic79

whack the tank with a nice size 2x4 it should make the pump work temporarily

yeah, do what he said. It always worked with the kids raising them. One good whack they worked for about a week to 10 days, then had to whack'em again.