Where have some of you guys that have changed over to elect water pumps, got your power feed from? Are there any switched circuits that have an additional 7 amps of capacity in the wiring, or do I just need to set a relay? I was looking at the fan supply circuit and the supply wiring looks oversized, but I have not had time to research the loads yet. The pump driveshaft was broken on my neighbor's car, and I bought a new Meziere pump for the car, since the drive gear/shaft is no longer available.


Regards, John McGraw

 

As the pump runs all the time preferred method is new supply through a relay triggered by a "key on" source

 

I used a 5 pin Bosch relay and 'triggered' it with the small pink wire on the front fan relay you can see in the picture. I used the side post battery cable bolts that have a fitting for an additiional smaller wire (any auto parts store) to get power to the relay and on to the pump.
Hope this helps.

 

Thanks guys,

I guess I will go all the way back to the battery and set a relay for "key on" operation.


Regards, John McGraw

 

Here is a segment from an article I wrote for installing an electric water pump. It's a little long but I think I covered everything:

All that is left is
the wiring. Meziere didn't give us what was really needed to wire this
pump up correctly. So, you need at least a 30 amp relay (Radio shack has
one, but a good electric fuel pump 30 amp relay might be better as far as
lasting longer). Another product that might be better is the Painless
brand electric water pump relay kit from Jeg's. I just didn't know
the amperage of the relay and it was $30. Also, I bought a 10-gauge wire
20 amp fuse holder with a few feet of 10-gauge wire. Some 10 - 12gauge
terminal ends, Insulated female receptacles to plug into the relay, butt
connectors to connect to the fuse holder and I eliminated the Mez plug
connector and went with butt connectors. A better way would be to use a
quality weather pack plug. Also, get some ring end terminals to connect
to the "jump-start junction block." In case you don't know what a
relay is for let me explain. The relay is a switch that keeps the high
drawing amperage components away from areas that shouldn't have high
amperage. The relay has a signal circuit that energizes the relay and
makes a high amp connection. The Mez pump is a high amperage draw and we
need a relay to turn it on. Where does the signal circuit get its power or
signal? I chose to use the "run-on, bulb test, crank" circuit which is
the one that is powered when the ignition switch is on. Where did I get
the power to run the pump? From the "jump-start junction block, which is
basically a direct shot from the battery. Okay, enough of electrics 101.
There is a block or junction of electrical wires connecting to one source
(a bolt with a nut) right behind the battery. This is 12 volt all the time
power. Put a ringed end terminal on it and run the wire to the relay you
bought. One of the tabs should say 12volt in. I mounted the fuse holder on
top of the ASR with the bolt that holds the cover on. I also mounted the
relay just under the ECM, there is a small plastic tab that sticks down
and I drilled a small hole for mounting the relay. Continue the wire from
the relay where it says 12volt out to the fuse holder. Connect the other
end of the fuse holder to the BLUE wire of the Mez pump. I dressed it into
the harness right along the edge of the fender. I used a butt connector
instead of the supplied plug (too cheap). Run the black wire from the pump
to a ground, I used the ground bolt just under the fan relays. Secure that
wire from the pump to the fan braces via tie wraps; don't want to have
it tangle with the serp belt. Now for the signal circuit. In my 92, the
run-on circuit runs to the fans and it is pink with a black stripe. You
can find it by tracing back from the cooling fan relays to a point where
you can make a splice. If you have any pink wire at the store, you can
keep the color correct for your circuit, or just use any 14 -16 gauge
wire. After making the splice, run the wire to the relay and connect to
the "on/off switch" tab. Run the remaining tab to ground. Again, I ran
it to the same bolt under the fans for ground. Recheck your connections
and that is it for the wiring. DON"T TEST IT YET UNLESS YOU HAVE
REFILLED THE COOLING SYSTEM. The instructions say don't run dry. If you
followed the wiring exactly, your pump will turn in the correct direction.
Blue gets the power and black goes to ground. Did you reconnect the
battery?

 

Got the pump in last night, and boy, it just barely clears the receiver/dryer on the A/C system! I should get it wired up and running tonight. For a job that I had planned on only taking 4-5 hours, this job has sucked almost a whole week.

First the broken driveshaft on the pump drive. That necessitated the removal of the front cover, which meant I had to remove the balancer hub (no small task in such a tight area), which meant removal of the oil pan, which meant removal of the starter and the oil filter adapter to be able to get at all the bolts. Of course, the pan will not come off the engine with it sitting on the mounts, so I had to unbolt the mounts and the exhaust pipes, so I could jack the engine enough to get the pan off. Then pull the timing gears and chain to be able to remove the waterpump gear and shaft. I then turned a plug out of some aluminum stock to fill the hole where the shaft used to come out, and sealed it in place with some silicone.

Then reverse the order of dis assembly and install new Optispark (the reason for the work to begin with), and install the electric pump.
I now have over 15 hours of total work on the car, and no way in hell I can charge my neighbor for this much labor, so I just ate a bunch of labor. My small blocks and LS engines are way easier to work on than the LT engine in a C4. This is definitely not a easy car to work on, especially for guys like me that have hands the size of suitcases!
My hands are so beat-up and cut-up from jamming then into tight spaces, that it will take a week for them to heal.


Regards, John McGraw

 

I feel your pain man, been there myself. I have little girlie hands and I still got all chewed up from sticking them in some of those tight places. I feel sorry for you guys with hands like catchers mitts!
Got all that stuff done with new seals and still have a small drip from somewhere up in the black hole area near the front of the engine. I just clean it off every couple of weeks, park over a piece of cardboard in the garage and hope it doesn't get worse. I really don't want to have to go back in there again.