Electric water pump puzzlement
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Teching In
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Electric water pump puzzlement Hi,
I'm installing a Meziere HD pump in an LT1 water pump and find the clearances between the sides of the blades on the impeller, and the housing, to be unbelievable to me.
I called Meziere and explained it to them, also stating that I intended to do some machine work on the housing to decrease the clearance. They suggested around .040 between the impeller and the housing which would leave room for temperature expansion.
In the process of measuring for what I was about to do, I realized that the housing surface that pairs with the impeller is conical. The stock impeller is also conical, and matches the housing.
The Meziere impeller is flat so it seems to me there is going to be a lot of spillage around the edges of the impeller blades.
Measuring from the surfaces of the motor and the housing, where they nest on one another I find the Meziere impeller sticks out .750". (I'm measuring with old tools but I'll be within .010" most likely.)
The closest part of the housing to the impeller blades is .885" and as it cones away it gets to .960". That's .135" and .210" of clearance respectfully. And, the impeller blades are only .420" tall.
Doesn't that sound like an awful lot of room for water to slip around the impeller instead of being pushed through by it?
My housing shows some chatter marks where the pump was run with a bad bearing but I can see original metal between the chatter marks so I don't think the housing is like this because of wear.
Are all LT1 pump impellers conical or did I just get some odd-ball? I'd appreciate hearing if anyone else has run into this.
Thanks,
Dan
I'm installing a Meziere HD pump in an LT1 water pump and find the clearances between the sides of the blades on the impeller, and the housing, to be unbelievable to me.
I called Meziere and explained it to them, also stating that I intended to do some machine work on the housing to decrease the clearance. They suggested around .040 between the impeller and the housing which would leave room for temperature expansion.
In the process of measuring for what I was about to do, I realized that the housing surface that pairs with the impeller is conical. The stock impeller is also conical, and matches the housing.
The Meziere impeller is flat so it seems to me there is going to be a lot of spillage around the edges of the impeller blades.
Measuring from the surfaces of the motor and the housing, where they nest on one another I find the Meziere impeller sticks out .750". (I'm measuring with old tools but I'll be within .010" most likely.)
The closest part of the housing to the impeller blades is .885" and as it cones away it gets to .960". That's .135" and .210" of clearance respectfully. And, the impeller blades are only .420" tall.
Doesn't that sound like an awful lot of room for water to slip around the impeller instead of being pushed through by it?
My housing shows some chatter marks where the pump was run with a bad bearing but I can see original metal between the chatter marks so I don't think the housing is like this because of wear.
Are all LT1 pump impellers conical or did I just get some odd-ball? I'd appreciate hearing if anyone else has run into this.
Thanks,
Dan
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OP
you should not have to do anything other than install the Meziere.
If you feel it is defective in some way, return it and get another
If I understand your post, you feel there is to big a gap between impeller and housing?
pics would help us understand more what your concern is.
FWIW my Meziere has been in for 17 years now
you should not have to do anything other than install the Meziere.
If you feel it is defective in some way, return it and get another
If I understand your post, you feel there is to big a gap between impeller and housing?
pics would help us understand more what your concern is.
FWIW my Meziere has been in for 17 years now
Thread Starter
Teching In
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Got some pics in an album on IMGUR here http://imgur.com/a/kpQmY
One shows the interior of the housing, hard to see the cone. Another showing the stock impeller against a straight edge back drop. and another showing the stock and the Meziere impellers face to face.
I just can't believe this is normal and that of all the people who have converted to Meziere, none questioned it.
The edges of the stock impeller blades do not show any wear, it is stainless steel, so this one, it looks to me, was manufactured conical.
Dan
One shows the interior of the housing, hard to see the cone. Another showing the stock impeller against a straight edge back drop. and another showing the stock and the Meziere impellers face to face.
I just can't believe this is normal and that of all the people who have converted to Meziere, none questioned it.
The edges of the stock impeller blades do not show any wear, it is stainless steel, so this one, it looks to me, was manufactured conical.
Dan
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Most who have the electric pumps are too busy believing in perpetual motion to see such a thing.
The electrics free up power by doing less work.
The "believers" will tell you it is more efficient so much so that multiple energy form changes are meaningless.
You are seeing how it can't be more efficient.
It is SUFFICIENT for cooling most street strip setups as is, accept that or use the mechanical, chasing making it more efficient is not going to gain you anything.
The electrics free up power by doing less work.
The "believers" will tell you it is more efficient so much so that multiple energy form changes are meaningless.
You are seeing how it can't be more efficient.
It is SUFFICIENT for cooling most street strip setups as is, accept that or use the mechanical, chasing making it more efficient is not going to gain you anything.
This is NOT a thread about how well an electric pump works vs. the stock pump-and let's keep it that way.
Let's get the OP's pump assembled & working. The man wants to go out cruising!
Let's get the OP's pump assembled & working. The man wants to go out cruising!
Last edited by Paul Bell; Oct 5, 2015 at 11:56 PM.
Thread Starter
Teching In
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Truth is, I'm gonna try it in a circle track car, so I'm willing to go to most any length to eliminate any weaknesses I can foresee.
In my view, merely assembling what I have, without modification, is a guaranteed failure.
Please don't tell me it can't work. I'll tell you whether or not it did when I'm done.
I intend to shim the area of the pump body, that will be in close proximity to the impeller blades, with a mechanically attached spacer that is flat and conforms to the impeller blade edges by .015 or less.
My purpose in opening this thread was to be sure I had a normal example of a GM pump and not some oddball pump, and maybe expose a deficiency that might explain why some seem to have better luck with the EWP than others.
Dan
In my view, merely assembling what I have, without modification, is a guaranteed failure.
Please don't tell me it can't work. I'll tell you whether or not it did when I'm done.
I intend to shim the area of the pump body, that will be in close proximity to the impeller blades, with a mechanically attached spacer that is flat and conforms to the impeller blade edges by .015 or less.
My purpose in opening this thread was to be sure I had a normal example of a GM pump and not some oddball pump, and maybe expose a deficiency that might explain why some seem to have better luck with the EWP than others.
Dan
I always post pics by clicking on te little yellow mountain button and then just selecting the picture from my phone or PC. If the file is too big, if it's on your phone, email it to yourself and select medium or small size when you send it and it resizes it. Or I upload it to my free cardomain site and then open the picture in a new window, and then copy and paste the url into the yellow mountain button prompt.
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Truth is, I'm gonna try it in a circle track car, so I'm willing to go to most any length to eliminate any weaknesses I can foresee.
In my view, merely assembling what I have, without modification, is a guaranteed failure.
Please don't tell me it can't work. I'll tell you whether or not it did when I'm done.
I intend to shim the area of the pump body, that will be in close proximity to the impeller blades, with a mechanically attached spacer that is flat and conforms to the impeller blade edges by .015 or less.
My purpose in opening this thread was to be sure I had a normal example of a GM pump and not some oddball pump, and maybe expose a deficiency that might explain why some seem to have better luck with the EWP than others.
Dan
In my view, merely assembling what I have, without modification, is a guaranteed failure.
Please don't tell me it can't work. I'll tell you whether or not it did when I'm done.
I intend to shim the area of the pump body, that will be in close proximity to the impeller blades, with a mechanically attached spacer that is flat and conforms to the impeller blade edges by .015 or less.
My purpose in opening this thread was to be sure I had a normal example of a GM pump and not some oddball pump, and maybe expose a deficiency that might explain why some seem to have better luck with the EWP than others.
Dan
just some inside stuff between all the regular members on the tech. What are your motor specs?? I'm still a little confused on your original question, are you saying the propellers in the pump aren't shaped like the ones SSRRR posted? And are you also saying with the pump on the clearances between the pump and the fan shroud on the car are very close?? If yours indeed fails, I believe I have a LT1 CSR EWP laying around somewhere... I chose to go with a Delco factory replacement pump. 
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Dan
it would appear that your pump went through some "self clearance" either on initial motor start up back when it was installed on the motor or the shaft the impeller is attached to developed play over a period of time causing the impeller to strike the housing. Or those marks are just errant machining marks made when it was cast/machined as a housing before assembly as a WP
If I understand your concern you feel there needs to be a tighter clearance between the impeller blades and housing?
A tighter clearance may or may not improve flow output but IMHO I would think Meziere in their R&D process would have designed the optimum clearance and design of their impeller or at least optimum without machining modifications to the stock housing.
A solid fuse/relay install is critical to good operation of a EWP. The pic SSR shows of the Meziere was what mine looked like 17 years ago when I bought it. I replaced that , IMHO cheap, inline barrel fuse with a "weather Pac" (OEM) type and also same for the connector. I believe Meziere now sells the EWP with the WeatherPac type connector now
If you do some form of modification, please post pics. Good luck with the swap
it would appear that your pump went through some "self clearance" either on initial motor start up back when it was installed on the motor or the shaft the impeller is attached to developed play over a period of time causing the impeller to strike the housing. Or those marks are just errant machining marks made when it was cast/machined as a housing before assembly as a WP
If I understand your concern you feel there needs to be a tighter clearance between the impeller blades and housing?
A tighter clearance may or may not improve flow output but IMHO I would think Meziere in their R&D process would have designed the optimum clearance and design of their impeller or at least optimum without machining modifications to the stock housing.
A solid fuse/relay install is critical to good operation of a EWP. The pic SSR shows of the Meziere was what mine looked like 17 years ago when I bought it. I replaced that , IMHO cheap, inline barrel fuse with a "weather Pac" (OEM) type and also same for the connector. I believe Meziere now sells the EWP with the WeatherPac type connector now
If you do some form of modification, please post pics. Good luck with the swap
Thread Starter
Teching In
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I got the pump used, don't know the history. The bearing was sloppy and the impeller blades were what scarred up the housing. I can still see original finish between the scars so I think the shape of the housing is substantially as manufactured.
I'm going to call Meziere again and see if I can get a feel for why they make it like they do.
My original conversation with them led to discussing my reducing the clearance . I'm thinking if their research had concluded that wide clearance didn't matter, the person I talked to would have said so and would not have suggested to me that .040" would be a dimension to shoot for.
If I'm right, then after modification I expect the pump to move more water with a corresponding increase of amperage drawn. That will be another topic I discuss with Meziere: what current level is the motor capable of sustaining without damage.
I'm thinking I'll protect it with a circuit breaker, size to be determined.
Dan
I'm going to call Meziere again and see if I can get a feel for why they make it like they do.
My original conversation with them led to discussing my reducing the clearance . I'm thinking if their research had concluded that wide clearance didn't matter, the person I talked to would have said so and would not have suggested to me that .040" would be a dimension to shoot for.
If I'm right, then after modification I expect the pump to move more water with a corresponding increase of amperage drawn. That will be another topic I discuss with Meziere: what current level is the motor capable of sustaining without damage.
I'm thinking I'll protect it with a circuit breaker, size to be determined.
Dan