What wire did you guys tap into for the "key on" wire?
I was thinking fuel pump.

 

Don't use the fuel pump wire
If anything tap into the alt wiring.Don't run the motor at anytime without the pump on,it will create hot spots in the heads and blow the engine

 

 

I used the pink-black stripe wire off of the fan relay for mine. Its hot anytime the ignition is on. Then for the power wire, I used a terminal block that is mounted behind the battery.

 

1.if you tap into the fuel pump directly, the water pump will turn on and off when the pump cycles before start.
2. if you use the fuel pump for the water pump, you will overload the fuse, and the fuel will shut off.
3. If you use the maf relay, you need to tap into the maf relay switched power and tie that to the water pump relay coil and pick up the water pump power right from the battery with an inline fuse.
So that you turn on the key, the maf power energizes the relay coil, the relay energizes, and battery power powers the water pump through the big contacts on the relay. turn off the key, the coil de-energises, and the contacts open, shutting off the water pump. if you want, you can use battery power to run the whole thing through a temp sender in the head so that the pump shuts off when the engine finally cools down, but you have to add a second fan in the front of the radiator that has it's own relay that is grounded by the temp sensor. Beware, you need a bigger battery to accomplish this.

 

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

 

Thanks for all the great replies guys. I've learned more about my car in six months than I could have learned on my own in six years. This forum is priceless.

 

Please use a Relay as stated in the above post , These Water pumps draw alot of current and should not share any other circuit.

Desert

PS:make sure and solder ALL connections , and use heat shrink tubing over ALL connections

 

I did the same thing. When my vette was stock the stock pump was leaking so I put the meziere on. I noticed a huge hp difference. And this was 2yrs ago. They are very reliable. Yeaaah for me this was my first mod.

 

This is a good description of what it takes to wire it up. I used the fuse block on the back of the fender in front of the battery. It has a screw there that allows easy access to a wire lug and it draws its power direct from the battery. I was afraid the other fuse block (behind the battery) was already pretty loaded down with electrics. I also tried to locate the relay in a cool spot for better reliability so I mounted it on the forward radiator shroud hold-down bolt near the fan ground--shorter wires that way.

 

Worked out great for me. Thanks again Rich!

 

Tom, don't be so modest. Here's the link to Strick's excellent tech-tip on the matter. Meziere Tech Tip

 

"Holy paragraph Batman"


Meziere HD Coolant Pump Install for the LT-1/4 Let me begin with my situation before I started this upgrade. I have a 92 LT-1 convertible with the 6 speed tranny. I had an oil leak coming from the driven shaft seal of the water pump. After removal of the water pump I saw that it was leaking coolant out of the weep hole right onto my opti-spark. After I removed the opti-spark and disassembled it, I found rust, coolant, and a lot of dirt inside. It was ready to leave me on the road; dead. Sound familiar? Instead of just replacing the OEM coolant pump, I did some research and found that electric water pumps work better than OEM pumps, especially on LT-1/4s, and they eliminate one possible source of an oil leak, while also eliminating the “weep hole leak” on to the opti-spark syndrome. Theoretically, you even get a few extra ponies. This article talks about installing the Meziere HD Coolant Pump and all the things I found necessary to do on my Vette along this trip. This project can include changing the opti-spark, wires, seals in the timing cover, and if necessary, the timing chain. This project will also eliminate possible oil leaks on the front of the engine, which was a problem for me. Now there is an argument for not removing the driven shaft that drives the OEM water pump. I personally don’t like the idea of something spinning around in the engine when it is not supported as designed. Too much chance of a future oil leak or worse a piece coming loose inside the timing cover for me. To start out, let me say that I used the Helms Service Manual for much of the procedures. For example, the service manual has an excellent checklist for removing the oil pan. I just added information that I had questions about and came up with solutions. Other tips came from you guys. So, use the manual and refer to my tips. Let me know if you find a better way to do something and I'll update the article. I guess I should come up with some "grocery list" of things to buy before starting the project: The Meziere HD coolant pump, 10 gauge wire, 14-16 gauge wire, terminals, 20 amp fuse holder with a mounting tab, a 30 amp relay with a mounting tab, Gaskets for the oil pan, timing cover, water pump, water pump O-ring (inside inspection plate), oil filter adapter (both gaskets), GM silicone sealer, GM assembly adhesive, serpentine belt (if needed), seals: timing cover crank and opti seals. I’d also, line up the ability to rent or borrow a Kent-Moore LT-1 hub puller/installer kit, J-39046 and a driven shaft remover might be needed (J-39243), but sometimes not required. Oh, about a 12 pack of your favorite adult beverage. First, I disconnected the battery. Next, drained the anti freeze coolant by removing both knock sensors and opening the radiator drain. Removed the air cleaner assembly, all of it. Removed the serpentine belt, I have the long tool designed for this, cheap at Pep Boys or so. To increase the working area in front of the engine, I removed the power steering pulley using a Lisle puller. I also removed the tensor; just one bolt holds it in. Disconnect the upper radiator hose at the coolant pump and use a bungee cord to hold out of the way. Also disconnect the bottom hose at the pump and move aside. Carefully disconnect the plug from the water pump sensor. Don't break the clip that holds the plug in. Now, you should have a good view of the coolant pump. You have 6 bolts to remove not 4. Once they are removed, pull the pump assembly off. It has two pins for alignment purposes. Put the bolts together (I used a coffee can and soaked them in solvent). There is a coupler that connects the pump drive to the driven shaft assembly that is inside the timing cover. Look carefully at the seal around this shaft in the timing cover, any sign of oil leaking here? If so, you'll have to take the driven gear assembly off and plug the hole in the timing cover, but that's later. Some guys just leave it in and if it doesn't leak, okay, but I don't think this is a good idea for the long run. I removed mine. That means removing the timing cover. Now for the not so easy task of removing the damper. You need to remove the damper to gain access to the opti-spark. There are 3 bolts that hold the damper onto the hub. I marked the damper so I could reinstall it in the same position on the hub, and it only goes on one way. After removing the 3 bolts, you'll probably have to get under the front end and using a soft drift pin or a wooden dowel (1 1/2" dia by 12" or so) and a hammer, loosen it from the hub. Don't just hit one part of the damper; try to hit it all around so it doesn't bind. This is a PITA. Once it comes free it is time for your first beer; you've earned it. Voila, the dreaded opti-spark is now in view. Mark each spark plug wire so you know where they go when it's time to reconnect. The opti-spark has the terminals marked and I made it easier to see by using a Sharpie marker. Pull the plug wires out of the opti-spark. Remove the coil wire as well. Now would be a good time to replace the plug wires if you want to. Remove the 3 bolts that hold the opti to the timing cover and soak them, too. Unplug the connector going to the opti (11 o'clock position as you look at the engine hope you don't have a digital watch). Carefully pull the opti off the timing cover and from this point on DON"T TURN THE ENGINE OVER, until we put the opti back on. If you are not replacing the opti, doesn’t turn the little gear that came out of the timing cover, this will make it easier to reinstall later. Time for one of the hardest part of the project IMHO. Hub removal. This is not like any other hub removal I've done. GM has a special tool kit just for the LT-1/4 it is "J-39046" it is worth its weight in gold. Time for a beer and enough for today. The next morning, I tackled the hub pulling. Using the Kent-Moore LT-1's instructions made it easier than expected. I did disconnect the hydraulic line going to the rack for better clearance. No, I did not have to raise the engine. Oh, before you pull the hub, make a mark on the timing cover and hub that matches so you can reinstall the hub in the same position. The Helm's manual makes a big point to make sure the damper is positioned back on the crank in the same position. Some say it doesn't matter, but I went with the manual and marked it. If your hub and damper were like mine they were pretty rusty, so I cleaned mine up and painted very lightly. Time for a beer thirty break. If you are going to take the timing cover off, you have to remove the oil pan. So, the next thing to do is drain the oil and remove the oil filter. My Helms manual had a good checklist to follow as far as removing the oil pan. One of the items to remove was the driver's side cat. I did it and found that it gave me lots of room to work. Just do it. It also said to remove the oil filter adapter, the part that the oil filter screws into. It has two gaskets to replace and this eliminates a possible oil leak down the road. Also, remove or at least raise the oil dipstick holder as it interferes with the oil pan gasket removal and install later. Remove the shields that go around the knock sensors if you haven't already done so. Remove the oil level sensor. The plug is a weather pack connector and using a small flat blade screwdriver, carefully disconnect this plug before unscrewing the sensor. Next, remove the starter, it's only two bolts and two wires and it probably needs to be cleaned anyway. Now remove the clutch inspection plate. I used my 1/4" drive set to remove the oil pan bolts as it seemed easier to work with. Here's another tip for you concerning the pan bolts and their positions, I used a shoebox top and punched holes in it similar to the oil pan's bolt pattern. This way I didn't loose any and I knew where each bolt went. I then loosened the oil pan and jockeyed it off. Later, I found that raising the engine just about 3/4" would have made this much easier. How do you raise the engine? On my LT-1 (92) there are two nuts that hold the motor mounts to the 45-degree cross members. Remove those nuts. The stud is just about 1" in length so you can judge by that how high to jack. Where to jack from? I have a 6 speed and I used a block of wood on my axle jack and raised the drive train from the bell housing. Remember, just 3/4" is all you'll need. After you get the oil pan off it might be a good idea to take a break. Timing cover removal is next. With the oil pan off, you can now remove the timing cover. Just remove the bolts (use the same shoebox method of saving the bolts). I had to LIGHTLY tap the bottom of the timing cover from under the car to break it loose. Clean the timing cover and oil pan and also start cleaning the mating surfaces on the block. Once I had the timing cover cleaned, I went to my local precision welder, Truecraft, and had him weld a piece of aluminum into the hole where the coolant pump drive came out. He did a great job, as you can't tell there was ever a hole there. He even polished it! This is the point of no return for this project. Oh, the price, $30. Cleaning the mating surfaces on the block was a long, tedious job. (At least two beers worth) The hardest surface was the water pump mating area. I went through several razor blades and a can of gasket remover. Lets take a look at the instructions for installing the Meziere Pump. It's just one page and seems easy. Take the water pump you took off your engine and remove the six bolts that hold the inspection cover on. Clean the mounting surfaces. Now, it's time to remove the "guts" of your old pump. Some guys beat it out with a hammer and a punch. I didn't like the idea of beating on a piece of aluminum, so I went to a machine shop and had the impeller and bearing assembly pressed out. Bring the Meziere instruction with you to the machine shop as it explains how to press it out. Once he has it pressed out, take a look at the inner seal right next to the bearing. Mine was cracked and coming apart, no wonder it was leaking out the weep hole. Definitely the weak part of the pump. While you are at the machine shop have him press in the freeze plug, supplied, into the hole where the bearing was seated. It's in the instructions and don't forget to use the Permatex Form a gasket. The instructions talked about plugging other holes, but the only hole to plug was the weep hole in mine and that is on the other side of the freeze plug. So, I disregarded that issue. Now, you should have a pump housing with the freeze plug installed. Some guys put an extra layer of sealer around the backside of the freeze plug. The guy in the shop had some sealer and put it on just before pressing the plug into position. Good seal. Ready to put the timing cover on? Install the new crank seal and opti seal into the cover. I used a little GM Assembly Adhesive pt# 12346141, around the outer edge of each seal. Now, the manual didn't say whether to use gasket sealers or not so, I used Permatex's Aviation Form-A-Gasket, LIGHTLY, on both sides of the new timing cover gasket and placed it on the timing cover. Make sure there is a little grease on the inner part of the crank seal. Place the timing cover in position on the block and torque the bolts to the setting in the Helm's manual ( 11N*m or 100lb. in.). Done, beer? Now for the oil pan. Did you really clean it up and maybe paint it? I did, Chevy red. This is a tough one and two people might make it easier, but I did it myself. First, I used GM Silicone sealer pt# 12346192. I used it to glue the oil pan gasket to the oil pan. Let it set, for at least an hour. I used it heavily on the end, where it mates with the timing cover. To hold it in place while drying, I used a 2-liter coke bottle filled with water as it was close to the radius of the pan. Go eat lunch or dinner as the time dictates. Once the gasket is firmly in place on the oil pan, it's time to jack the engine up again, remember just about 3/4". The manual describes where a bead of GM pt# 12346192 must be put to ensure a good seal between the joints at the corners. I chose to put the bead on the gasket just before I put the pan on. It just seemed easier and neater. CAREFULLY, jockey the oil pan into position. The place to watch is the front part of the oil pan gasket where it mates with the timing cover. Tip, I made a few trial fit tests with the pan before I put the bead of sealer on the corners. If you have to rotate the engine so you have clearance, remember to mark the crank so you can get it back for the opti and hub install. Okay, hopefully, you got the pan in place and you started a few pan bolts to hold it in place. Before you tighten it down, recheck the mating around the timing cover. Put the rest of the bolts in and torque (corners to 23N*m or 17lb-ft and remainder to 11N8m or 101 lb-in). I hope you didn't forget the reinforcement strips like I did. No problem, just do one side at a time. It is time to put the oil filter adapter back on with its new gaskets. These go on dry. Make sure the O-ring gasket is correctly in the groove. I used a little Vaseline Jelly on the O-ring. Check the manual for the torque setting (23N*m or 17lbs-ft). Lower the engine and reinstall the engine mounting nuts. Time for a break. Let's finish up underneath the car. Put the cat back on. Put the knock sensors back in. Put the oil level sensor back in (22N*m or 16lb-ft) with the plug and install the clutch inspection plate. Install the starter (take a look at the # 8 plug it might be easy to change before installing the starter depending on your headers). Recheck everything under the car making sure all the wires are connected. Close the radiator drain on your way out. The hub installation is next. . Just a word I should have talked about before, if your hub has a wear spot around where the seal would ride, you might want to replace it or buy a sleeve that goes around it. Mine was fine, and I just cleaned it up and put a little grease around it before installation. Get out your Kent-Moore LT-1 hub installation tool. Read the instruction and line up the hub to your marks you made previously. Using the installer push the hub into position, watch that the seal slips nicely around the hub. Remove the installer and put in the hub retaining bolt torque to 95N*m or 70 lb-ft. If you removed the hydraulic line going to the rack, replace it. Time to install the opti-spark. Before you install the opti, some guys, including myself, put a bead of silicone around the edge of the cap for a better seal against moisture. Notice on the spline shaft gear (connects the opti to the cam) that there is a small "keyway" so it will only install one way. I greased the seal part and inserted it into the cam through the timing cover. Don't try to hammer it in. It will slide in when positioned correctly. Now, you have to line up this gear with the opti gear (same "keyway") as you position the opti in place on the timing cover. Be patient and don't force it. Once it slips into place, have a bolt ready to go to hold the opti in place. Put the other bolts in place and torque to 11N*m or 8lb-ft. Reconnect the plug wires and the coil wire. Don't forget to plug in the distributor connector. I put a seal of silicone around this connector so water won't be able to enter the opti from here. Now you're ready for the damper. Just install using the three bolts torque to 81 N*m or 60 lb-ft. Coolant pump install. Before you install the housing, do you want to change the thermostat? Now would be a good time. I installed the mounting housing first and then installed the Meziere pump. To install the pump housing, I used Permatex Aviation Form-A-Gasket on both sides of the water pump gaskets. Slide the housing into position and push to seat. Remember there are two alignment pins to help out. I put Permatex sealer on the bolts as I put them in and torqued to 41N*m or 30 lb-ft. Finally, we're ready to mount the Meziere HD coolant pump! I bought a new O-ring gasket to fit around the Mez pump where it fits into the housing. My old one was flat and a little hard. I hope you didn't lose those 6 little bolts that held the inspection plate on. These hold the pump in place. Don't over tighten. I didn't have a torque for them so be gentle. Oh, I had to loosen the A/C accumulator to make room for the Mez pump. There, ain't it pretty? Now reinstall the belt tensor. Put the power steering gear pulley back on and put the serpentine belt on. Reattach all the hoses. It's definitely time for a brew. 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? Refill the oil and cooling systems. I don't use DEXCOOL; I just use the GREEN STUFF and distilled water. After you have coolant in your system turn the key on and look inside the expansion tank to see if it is flowing. Hopefully it is. This makes it easy to top off the system with the pump running. Take one more look under and through the car before you give it a test drive. Bring an extra fuse and a jumper wire in case the relay fails. You can just pull the two 12 volt wires off the relay and connect via a jumper wire with blade terminals on it. This will get you back home. Most guys carry an extra relay, just in case. Don't give Murphy a chance to strike. That's it. One thing that made this project easier was my Kwik Lift. It's a drive on ramp that you jack up. Gives you about 20 inches under the car. And it makes things safer. Hope this helps. See ya Strick

 

I never said I was an English major.

 

Just in case you're thinking of taking it to the track, here's another option you can go with. Make a "street/race" mode switch, using a double-throw switch. One side is fully automatic (comes on with the ignition), and the other side is manual (constant hot...runs with the ignition switched off)... perfect for between rounds cooling at the track (dragstrip or road course).

Here's how:
On the switched side of the water pump relay (you ARE using a relay for the pump, I assume), run a wire to the center terminal of the double throw switch. On one side of the DT switch, run the switched feed wire (MAF relay, whatever you use), and on the other side of the switch, run a battery feed wire (to the hot-feed junction block, battery positive terminal, back of the alternator..you get the idea).

Now you have the capability to help cool the engine down between runs at the track, and have "set it and forget it" for the street.

Just FYI...

 

Yes, I am using a relay and I do plan on adding a switch for racing. I already have a switch wired into my fans that turn both on whenever I want by grounding them. It has worked excellent so far, my coolant temp is exatly the same ever time I go to the line. I figured I will need to circulate the coolant through the engine with it off when the summer temps arrive. Thanks.