DIY electric water pump - on the cheap

[Daox]

That would be great if you could test yours under different conditions.

[Daox]

The other night I started working on the key for the pulley. I chopped it out of some 3/8" plate I had kicking around. It still needs to be trimmed up a bit, but I ran out of grinding wheels, so that'll get finished up another night.

Here are the pics:

As mentioned, I cut this out of 3/8" plate. Its supposed to be 1/4" x 3/16" x 1-1/2", so it took some grinding. I just went at it with an angle grinder to get it to shape. Trial fit, then grind some more, trial fit, grind, rinse repeat. Then, I drilled two 1/8" holes. These aren't the right size for the #6 tapped holes, but its what I had and its close enough.





With the holes drilled, I could tap them.





And here we have it assembled. The key fits great and does its job. The pulley actually fits a bit looser than I'd like on the shaft. I must not have double checked my dimensions before printing. It will still probably work.







Here is everything bolted up to the motor. As I mentioned, the key still needs to be ground down in the middle so the nut fits on all the way. But, it all goes together quite well. I'm happy with it.

[Hyperaboutmpg]

Definitely worth implementing to save about 3hp in 1 l motor [used old Hot Rod mag data, probably way high from your comments] which can be put to good use. Check with moroso co., they are the leaders. Durability of electric motor is the real issue, and re engineering of coolant and electrical system. Good fortune with your project. TD

[Daox]

I don't think the water pump will take anywhere near 3hp. But, soon we will know exactly how much power it'll take.

I worked on the mount a bit the other night. There ended up not being enough room above the engine mount on the Metro, so I'll have to mount it under it. I actually decided to use the engine mount as the mounting point. Its the part that is rigid to the engine, so it should work out well.

I started out with two pieces of angle iron. These will straddle the engine mount.





Two slots were cut for bolt clearance. I oversized them and slotted them for adjustment to get the belt to light up.





Here is the test fit on the car. My mounting plate gets sandwiched between the two motor mount pieces.







The vertical part of my mount will continue down, and then flare out. The flared section will have holes for the motor to mount to.

[MetroMPG]

Fabrication is fun.

The pics makes sense to me because I know where the water pump is in relation to the mount ("up" in those pics).

[Daox]

Here are a few pictures I posted before that'll help show things. The engine mount is on the lower right in both pictures.

[California98Civic]

Pretty cool. I can see it too, having worked on a friend's metro a little. Great little cars. If you really get 3hp worth of power savings, that'll make quite a difference with this little car. What is that 4 or 5% of total hp that engine produces?

[Daox]

3hp would be 5.4%!

As oilpan noted though, his pumps pull less than 100W, so only a fraction of a horsepower.

I'm really not sure what kind of gains I'll see, there are a lot of variables here. The closest thing I can compare it to is an alternator delete. The Metro only uses 128W to power itself while idling according to MetroMPG's testing. But, that is exaggerated by the alternator's inefficiency, so its probably closer to 250W of engine power. Say the water pump uses 80W, thats 1/4th the gain. MetroMPG saw a 10% gain from de-belting his alternator (but kept a belt on his a water pump). I'll be debelting everything. So, my guess at this point is probably 3-4%.

[Daox]

No progress on mounting things, but I did get a chance to work on the electrical side of the setup. I grabbed the arduino, wrote a quick test program where it increments in 8.3% increments. This simulates 500 rpm increments of 0-6000 rpm. The same program will be run once the motor is installed on the car to measure the load of the water pump at the different rpms.

I made a video that shows this much better than typing out a ton of stuff.

https://www.youtube.com/watch?v=qp8r...ature=youtu.be

[jeff88]

Daox, I'm not sure if anybody else is having problems, but I'm am getting the private video error.