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  • 92CelicaHalfTrac

    April 29, 2011 10:11 a.m. 92CelicaHalfTrac SuperDork

    Ran across this:

    http://www.king6fab.com/pumpblockoff.html

    Got me thinking, since replacing the factory water pump on this motor is a major pain in the rear. If i were to purchase this, exactly what am i looking for in a pump?

    What are the pros/cons to doing a setup like this? Obviously, one less belt to run, less parasitic drag on motor, at the expense of more install work, but replacements down the road would be a breeze.

  • mad_machine

    April 29, 2011 10:15 a.m. mad_machine SuperDork

    Not sure how it is one less belt to run. Classic SAAB 900s use an external pump that is in all reality, a regular pump inside an external housing. Works well and is WAY easier than trying to work on the front of that engine

  • 92CelicaHalfTrac

    April 29, 2011 10:18 a.m. 92CelicaHalfTrac SuperDork

    mad_machine wrote:

    Not sure how it is one less belt to run. Classic SAAB 900s use an external pump that is in all reality, a regular pump inside an external housing. Works well and is WAY easier than trying to work on the front of that engine

    Would be replacing with an electric pump in this case. I should have specified in the original post, sorry.

  • tuna55

    April 29, 2011 10:23 a.m. tuna55 SuperDork

    I don't see an issue so long as the pump you're using is OEM quality or better, which is a pretty tall order. I know that most of the drag race style electric pumps are not meant for street use. This means that the 30 miles of racing they'll encounter during the season is fine and dandy, but thousands is probably not a great plan.

  • GameboyRMH

    April 29, 2011 10:44 a.m. GameboyRMH SuperDork

    Pro: One less belt, and if you get a "smart" one that adjusts pump speed with temperature, better efficiency and potentially more cooling power.

    Con: A tiny bit of weight, so little it wouldn't even be worth worrying about on a bike.

    I say go for it!

  • 92CelicaHalfTrac

    April 29, 2011 10:47 a.m. 92CelicaHalfTrac SuperDork

    tuna55 wrote:

    I don't see an issue so long as the pump you're using is OEM quality or better, which is a pretty tall order. I know that most of the drag race style electric pumps are not meant for street use. This means that the 30 miles of racing they'll encounter during the season is fine and dandy, but thousands is probably not a great plan.

    Ahhhh. See, this isn't something i would have thought of. This is why i ask GRM.

  • tuna55

    April 29, 2011 10:48 a.m. tuna55 SuperDork

    Oh - and you're not really reducing parasitic drag much - it still has to get the same amount of power from somewhere. Instead of getting it from the belt, it gets it from the alternator. Neither is particularly inefficient.

  • 92CelicaHalfTrac

    April 29, 2011 10:50 a.m. 92CelicaHalfTrac SuperDork

    tuna55 wrote:

    Oh - and you're not really reducing parasitic drag much - it still has to get the same amount of power from somewhere. Instead of getting it from the belt, it gets it from the alternator. Neither is particularly inefficient.

    True, but one less pulley to turn, and eliminates the horrible job of replacing an oil pump on this motor. Those were the main things i was going for.

    I'm not sure i understand what to look for in a pump, though.

  • BobOfTheFuture

    April 29, 2011 10:53 a.m. BobOfTheFuture HalfDork

    Yeah, parisitic drag doesnt change, but rotable weight does.

  • 92CelicaHalfTrac

    April 29, 2011 10:56 a.m. 92CelicaHalfTrac SuperDork

    BobOfTheFuture wrote:

    Yeah, parisitic drag doesnt change, but rotable weight does.

    That's the term i was looking for, thanks!

  • tuna55

    April 29, 2011 10:59 a.m. tuna55 SuperDork

    92CelicaHalfTrac wrote:

    tuna55 wrote:

    Oh - and you're not really reducing parasitic drag much - it still has to get the same amount of power from somewhere. Instead of getting it from the belt, it gets it from the alternator. Neither is particularly inefficient.

    True, but one less pulley to turn, and eliminates the horrible job of replacing an oil pump on this motor. Those were the main things i was going for.

    I'm not sure i understand what to look for in a pump, though.

    If I were in the market for an external electric water pump I would either look at big dollar builds to see what they used or go industrial. Figure out your flowrate and pressure vs RPM curve for the mechanical pump and find an appropriate equivalent from any one of a hundred industrial manufacturers, maybe check mcmaster for starters. They are bound to be rated for longevity. Either that or find an OEM who used one and buy one of those. Durability is a big issue.

  • 92CelicaHalfTrac

    April 29, 2011 11:01 a.m. 92CelicaHalfTrac SuperDork

    Found this one... but i'm unsure at the moment if the fitting options will work for my application.

    http://www.meziere.com/ps-793-761-wp116s.aspx

    Rated for 2500+ hours of use.

  • mad_machine

    April 29, 2011 11:11 a.m. mad_machine SuperDork

    even the pump I use for heat here in my house will eventually go bad.. seems like every couple of years the landlord has had to replace it

  • tuna55

    April 29, 2011 11:16 a.m. tuna55 SuperDork

    92CelicaHalfTrac wrote:

    Found this one... but i'm unsure at the moment if the fitting options will work for my application.

    http://www.meziere.com/ps-793-761-wp116s.aspx

    Rated for 2500+ hours of use.

    Depends on how much you drive. If I only commuted in my car, I drive about an hour per working day, so roughly ten years. Not awful. Weekend road trips will kill it fast.

  • 92CelicaHalfTrac

    April 29, 2011 11:30 a.m. 92CelicaHalfTrac SuperDork

    tuna55 wrote:

    92CelicaHalfTrac wrote:

    Found this one... but i'm unsure at the moment if the fitting options will work for my application.

    http://www.meziere.com/ps-793-761-wp116s.aspx

    Rated for 2500+ hours of use.

    Depends on how much you drive. If I only commuted in my car, I drive about an hour per working day, so roughly ten years. Not awful. Weekend road trips will kill it fast.

    Summer car only, not daily driven. Should have specified (man i sucked when i made this thread.) that this is pertaining to the SMF Escort.

    New question: what about t-stat bypass for heater core and such? I understand that even when the t-stat is closed, coolant is circulating. How would i simulate that with an electric pump? Does an OEM water pump typically have TWO inlets? One from radiator, one from bypass circuit?

    In case you can't tell, i've never really messed with this stuff before, just trying to learn and see if this will be worth it in the end.

  • tuna55

    April 29, 2011 11:34 a.m. tuna55 SuperDork

    92CelicaHalfTrac wrote:

    tuna55 wrote:

    92CelicaHalfTrac wrote:

    Found this one... but i'm unsure at the moment if the fitting options will work for my application.

    http://www.meziere.com/ps-793-761-wp116s.aspx

    Rated for 2500+ hours of use.

    Depends on how much you drive. If I only commuted in my car, I drive about an hour per working day, so roughly ten years. Not awful. Weekend road trips will kill it fast.

    Summer car only, not daily driven. Should have specified (man i sucked when i made this thread.) that this is pertaining to the SMF Escort.

    New question: what about t-stat bypass for heater core and such? I understand that even when the t-stat is closed, coolant is circulating. How would i simulate that with an electric pump? Does an OEM water pump typically have TWO inlets? One from radiator, one from bypass circuit?

    In case you can't tell, i've never really messed with this stuff before, just trying to learn and see if this will be worth it in the end.

    I have never been sure of that, actually. I would guess that the bypass point might differ from car to car. On a Civic, for instance, the water pump is just an impeller and a pulley with a flange between them, so obviously the bypass is in the block/head.

    For an occasional use car, that pump will be fine, and they are a known name brand.

  • 92CelicaHalfTrac

    April 29, 2011 11:36 a.m. 92CelicaHalfTrac SuperDork

    tuna55 wrote:

    92CelicaHalfTrac wrote:

    tuna55 wrote:

    92CelicaHalfTrac wrote:

    Found this one... but i'm unsure at the moment if the fitting options will work for my application.

    http://www.meziere.com/ps-793-761-wp116s.aspx

    Rated for 2500+ hours of use.

    Depends on how much you drive. If I only commuted in my car, I drive about an hour per working day, so roughly ten years. Not awful. Weekend road trips will kill it fast.

    Summer car only, not daily driven. Should have specified (man i sucked when i made this thread.) that this is pertaining to the SMF Escort.

    New question: what about t-stat bypass for heater core and such? I understand that even when the t-stat is closed, coolant is circulating. How would i simulate that with an electric pump? Does an OEM water pump typically have TWO inlets? One from radiator, one from bypass circuit?

    In case you can't tell, i've never really messed with this stuff before, just trying to learn and see if this will be worth it in the end.

    I have never been sure of that, actually. I would guess that the bypass point might differ from car to car. On a Civic, for instance, the water pump is just an impeller and a pulley with a flange between them, so obviously the bypass is in the block/head.

    For an occasional use car, that pump will be fine, and they are a known name brand.

    Yeah, i'm kindof leaning towards the bypass being in the motor... i don't think i've ever seen a stock pump with more than one "inlet." As such, i'm thinking that if i put the electric pump inline with the lower radiator hose, i should still have a functioning bypass, and circulation even with t-stat closed. That sound correct?

  • tuna55

    April 29, 2011 11:46 a.m. tuna55 SuperDork

    92CelicaHalfTrac wrote:

    tuna55 wrote:

    92CelicaHalfTrac wrote:

    tuna55 wrote:

    92CelicaHalfTrac wrote:

    Found this one... but i'm unsure at the moment if the fitting options will work for my application.

    http://www.meziere.com/ps-793-761-wp116s.aspx

    Rated for 2500+ hours of use.

    Depends on how much you drive. If I only commuted in my car, I drive about an hour per working day, so roughly ten years. Not awful. Weekend road trips will kill it fast.

    Summer car only, not daily driven. Should have specified (man i sucked when i made this thread.) that this is pertaining to the SMF Escort.

    New question: what about t-stat bypass for heater core and such? I understand that even when the t-stat is closed, coolant is circulating. How would i simulate that with an electric pump? Does an OEM water pump typically have TWO inlets? One from radiator, one from bypass circuit?

    In case you can't tell, i've never really messed with this stuff before, just trying to learn and see if this will be worth it in the end.

    I have never been sure of that, actually. I would guess that the bypass point might differ from car to car. On a Civic, for instance, the water pump is just an impeller and a pulley with a flange between them, so obviously the bypass is in the block/head.

    For an occasional use car, that pump will be fine, and they are a known name brand.

    Yeah, i'm kindof leaning towards the bypass being in the motor... i don't think i've ever seen a stock pump with more than one "inlet." As such, i'm thinking that if i put the electric pump inline with the lower radiator hose, i should still have a functioning bypass, and circulation even with t-stat closed. That sound correct?

    To me, sure, but who the flip cares what I think? Just keep it low so that it won't ever have cavitation issues and make sure that it can't suck the inlet hose closed. Springs in the hose can fix that latter issue.

  • ditchdigger

    April 29, 2011 1:50 p.m. ditchdigger HalfDork

    I am using the Meziere WP136s. When I made my block off plate I just welded a 1" npt nipple to it and hooked the output from the pump to that since the Fiat's water pump is already "external".

    2 years of daily driving service with zero failures or hiccups of any kind. I have one of the only rear engine fiats with no cooling problems. It actually runs a tad too cool even forcing 12psi of boost into the poor thing.

    I love my electric water pump

  • 92CelicaHalfTrac

    April 29, 2011 1:53 p.m. 92CelicaHalfTrac SuperDork

    ^Thank you sir!

    Now i just have to figure out if i'd be doing something bad just hooking the pump up inline to my lower radiator hose.

  • ditchdigger

    April 29, 2011 2:21 p.m. ditchdigger HalfDork

    Can't see why it would matter where the pressure source is as long as the coolant travels the same direction it did before and the thermostat bypass is still functional so the pump does not deadhead.

    Mine is located in the lower rad hose so it never has a problem priming. One of the neat things about the electric pump is that I can switch the key on with the engine not running and the pump will circulate the coolant as I fill it. This is handy as I can ensure my heater core (and therefore my whole system) is full without having to burp it later while it is running.

    You can also just run the water pump for a while say after a hard auto-x run and cool the turbo and whatnot.

  • red5_02

    April 29, 2011 2:57 p.m. red5_02 Reader

    Go to www.themazdaforum.com and look up a guy by the name of MP5T. Dude's a bit of a legend over there and should be able to tell you everything you need to know about what you're doing. His name is Brian and he's a no BS kind of guy. But if you have real questions he'll give you real answers.

  • 92CelicaHalfTrac

    April 29, 2011 3:13 p.m. 92CelicaHalfTrac SuperDork

    red5_02 wrote:

    Go to www.themazdaforum.com and look up a guy by the name of MP5T. Dude's a bit of a legend over there and should be able to tell you everything you need to know about what you're doing. His name is Brian and he's a no BS kind of guy. But if you have real questions he'll give you real answers.

    Brian's build thread on ClubProtege is what made me put 2 and 2 together once i saw the King6 blockoff unit.

    I'll shoot him a PM and see if he can get me a diagram of his setup. He didn't seem to explain where he put the pump.

    Thanks!

  • red5_02

    April 29, 2011 3:21 p.m. red5_02 Reader

    I'm pretty sure he has a diagram on one of his threads on TMF, if not I'm sure he'd send you one.

  • 92CelicaHalfTrac

    April 29, 2011 3:23 p.m. 92CelicaHalfTrac SuperDork

    Need to register to really navigate that site, i'll shoot him a PM on ClubProtege, thanks!

 
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