EWP back to stock?
Thread Starter
Instructor
Joined: Mar 2012
Posts: 170
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From: NH
EWP back to stock?
How difficult is it to convert from a Meziere EWP back to the stock mechanical pump? A PO put in a Meziere HD and wiring job was horrendous, I finally got the wiring as good as I could without redoing it all last week and then last night, I was overheating and the pump wont come on. I have voltage going in, and the ground checks out so the only thing I can think of is the pump finally died. It looks like there is about a $100 difference in price so if it doesnt take that much work to put it back to stock waterpump, then I would just rather do that. For me, the benefits of each option are kind of a wash, I am just looking at the amount of work to get my car back on the road. A Meziere is about $300 and I will have to properly wire it, and I will want to finally put the alarm in, or a stock pump for $200 and however much work to get it back to that. Thanks.
Racer
Joined: Jun 2010
Posts: 365
Likes: 27
From: Shelby Township Michigan
It's not that hard, but make sure the relay isn't bad.
If you decide to swap make sure the water pump drive gear wasn't removed. If it was i would just get another EWP.
Remove the water pump housing and at the top of the timing cover there should be a protruding shaft from the drive gear. If not it was removed. If the gear is there, you should probably replace the seal. Then you'll need the coupler (find one of these before you convert back) that goes between the shaft and pump. It slides on the spline. Then I would install a brand new pump. Swap over the coolant sensor or replace it and then remove all the wiring from the electric pump.
If you decide to swap make sure the water pump drive gear wasn't removed. If it was i would just get another EWP.
Remove the water pump housing and at the top of the timing cover there should be a protruding shaft from the drive gear. If not it was removed. If the gear is there, you should probably replace the seal. Then you'll need the coupler (find one of these before you convert back) that goes between the shaft and pump. It slides on the spline. Then I would install a brand new pump. Swap over the coolant sensor or replace it and then remove all the wiring from the electric pump.
Thread Starter
Instructor
Joined: Mar 2012
Posts: 170
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From: NH
There is no relay, its just hacked directly out of the fuse box. Power comes from a line stuffed into the backup light fuse with a 30A fuse, line runs through the door jam and follows the harness along the firewall, along drivers side valve cover into the EWP connector. The ground runs to the drivers side frame by the fans. Both signals into the EWP appear good. I recently got the wiring kit from Meziere to rewire becuase I was sick of looking at this, but only ever got as far as fixing all the intermittant connections so I could drive it. Website says these are good for 3000+ hours, who knows how old it is and I am sure the crap wiring job didnt help.
Thread Starter
Instructor
Joined: Mar 2012
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From: NH
Great idea. The pump didnt work. I called Meziere and they can actually rebuild them for about $100-150 depending on what it needs. I had it out in about 15 min so it looks like thats the best option and then I will rewire properly.
Thread Starter
Instructor
Joined: Mar 2012
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From: NH
All of the instructions appear to call out an O-ring for the EWP into the pump housing. when I took it apart, I didnt find any O-ring, only a flat gasket. I have everything mounted in and re-wired to use the relay. I want to buy a new gasket becuase I dont think I will be able to re-use it and I want to make sure I get the right thing. Using the GM PN (10128329) that I found on various forum entries, I can't get any pictures to make sure it looks right. Any help?
Race Director
Joined: Apr 2000
Posts: 15,344
Likes: 4,009
From: Texas
If your question is about installing a stock pump, then there can be some work involved...
- If the PO did it right, they removed the waterpump driveshaft assembly from the block and sealed the hole in the timing cover
- To replace the assembly you have to pull the timing cover, which means you have to drop the oil pan
- You have to hope that they didn't screw up the cover when they installed the plug such that you can install a new seal
Here's what I don't recall....Is the waterpump driveshaft assembly installed from the lifter valley side of the block or the front? If the former, then you have to pull the intake as well. I think it's pressed in from the front but you'll need to check.
Lastly, you have to hope the GM timing set or equivalent is there since it drives the waterpump driveshaft. If it's not (lots of people dump them and install a double roller or a conventional setup), you will have to buy a new set...gears and chain...which are $$
Bottom line...cheaper and easier to fix and keep the Meziere.
- If the PO did it right, they removed the waterpump driveshaft assembly from the block and sealed the hole in the timing cover
- To replace the assembly you have to pull the timing cover, which means you have to drop the oil pan
- You have to hope that they didn't screw up the cover when they installed the plug such that you can install a new seal
Here's what I don't recall....Is the waterpump driveshaft assembly installed from the lifter valley side of the block or the front? If the former, then you have to pull the intake as well. I think it's pressed in from the front but you'll need to check.
Lastly, you have to hope the GM timing set or equivalent is there since it drives the waterpump driveshaft. If it's not (lots of people dump them and install a double roller or a conventional setup), you will have to buy a new set...gears and chain...which are $$
Bottom line...cheaper and easier to fix and keep the Meziere.
Le Mans Master
Joined: Apr 2000
Posts: 5,713
Likes: 105
From: Manassas VA
Assuming the pump is ok, here is the kit I used for wiring. http://www.ecklerscorvette.com/corve...1984-1992.html
It is a fan relay just like the 2 you have now on the fans. The kit makes for a nice install and the relays are rated for at least double the amps the pump pulls.
What I did was use the Pink? wire for signal coming off of the fan relay. Its always hot when the ignition is on. Then ran the power wire from a good source ie, battery. Ground the pump to the frame. Mine has been like this for years with no problem.
Another advantage to using this relay kit is, if in the event of a relay failure, you could swap out one of the fan relays to limp it on home.
If you want me to look at mine again to verify wire colors and connection spots let me know. Its been years since I did the work.
It is a fan relay just like the 2 you have now on the fans. The kit makes for a nice install and the relays are rated for at least double the amps the pump pulls.
What I did was use the Pink? wire for signal coming off of the fan relay. Its always hot when the ignition is on. Then ran the power wire from a good source ie, battery. Ground the pump to the frame. Mine has been like this for years with no problem.
Another advantage to using this relay kit is, if in the event of a relay failure, you could swap out one of the fan relays to limp it on home.
If you want me to look at mine again to verify wire colors and connection spots let me know. Its been years since I did the work.
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Thread Starter
Instructor
Joined: Mar 2012
Posts: 170
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From: NH
I dont think my question was that clear. I had the EWP rebuilt by Meziere, I also purchased the wiring kit from Meziere and I ripped out the hack job from the PO. Pump is in, wiring is in, pump works. The problemis that I did not get any kind of seal to replace what was there between the EWP and the water pump housing and I dont think I am going to get by re-using what was there. The question is, every thing I read refers to that seal as an o-ring and I have a flat gasket with the bolt pattern in it stuck to the water pump housing. Is the PN 10128329 an o-ring or gasket? I dont want to get the wrong part as shipping is going to be twice the cost of the part.
Le Mans Master
Joined: Apr 2000
Posts: 5,713
Likes: 105
From: Manassas VA
I dont think my question was that clear. I had the EWP rebuilt by Meziere, I also purchased the wiring kit from Meziere and I ripped out the hack job from the PO. Pump is in, wiring is in, pump works. The problemis that I did not get any kind of seal to replace what was there between the EWP and the water pump housing and I dont think I am going to get by re-using what was there. The question is, every thing I read refers to that seal as an o-ring and I have a flat gasket with the bolt pattern in it stuck to the water pump housing. Is the PN 10128329 an o-ring or gasket? I dont want to get the wrong part as shipping is going to be twice the cost of the part.
I didn't see the post where you said that you had the pump rebuilt or that you got the relay....... In the beginning you speak of how expensive the pump is and what it will cost to get it rebuilt. Latter you speak of the pump direct wired direct out of the fuse box. I just missed that part.
But as far as the o-ring goes by doing a google search here is what I found http://www.rmsautoparts.com/proddeta...?prod=10128329
and FWIW it is supposed to be a o-ring and not a gasket
Thread Starter
Instructor
Joined: Mar 2012
Posts: 170
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From: NH
Thanks for all the help guys, got my rebuilt motor in and rewired it along with a bunch of other harness clean up this past weekend. Vette is back on the road and a lot cleaner under the hood. The gasket that was on there appears to be holding, so I think I will just leave well enough alone.