Water pump mechanical to electric

The Gen3 has a different engine so compatibility is questionable. There are standard part kits to drive mechanical pumps by electric motors. Take a look at one for the 1.5 liter Toyota engine and check for mechanical clearance.

JeffD

 

They are different engine families.

The 2010 uses a 1.8 l ZR engine Toyota ZR engine - Wikipedia, the free encyclopedia

The 2001 to 2009 uses a 1.5 l NZ engine Toyota NZ engine - Wikipedia, the free encyclopedia

I am not aware that the 2001 to 2009 had any accessories running at 201 v DC, which is what the 2010 water pump uses, I think.

 

Speculation but you might consider getting one or more 12 V. heater coolant pumps and doing the plumbing to use them. It then remains a plumbing and control law problem.

Bob Wilson

 

Why change to electric?

 

Switching to electric drive prevents a spike in temperature when the ICE shuts down (The Prius ICE does this a lot). You can put a time delay relay in the electrical circuit to keep the coolant flowing for a short time every tine the ICE stops.

JeffD

A complete electric water pump
http://www.daviescraig.com.au/Images/Categories/EWP Selection Guide & Tech Specs 2009.pdf

An example Electric adapter drive (not for a Prius)
Mr. Gasket 4333 Electric Water Pump Drive Kit JEGS: eBay Motors (item 400158123945 end time Oct-26-10 07:04:12 PDT)

 

I suspect you would have to remove the mechanical water pump as the impeller would probably restrict coolant flow.

It would be a fairly big job. Remove the pump, make blocker plate. Find sufficient volume electric pump. Design and build control circuitry.

The belt lasts until it disintegrates due to age, not wear. It's not a big issue you are trying to "solve". It won't result in measurable mileage changes.

But if it makes you happy go for it.

 

My answer is that the Toyota powertrain engineers were not happy unless they could introduce yet another component that will provide zero advance notice of an impending failure.

At least with the mechanical engine coolant pump, visual inspection provides a clue of a pending failure, and the pump still operates - it just has a slight leak in the bearing.

With an electric pump, one day it is great and the next day it stops working with no clue provided to the driver until you see the red thermometer icon appear in the MFD.

The 2G inverter coolant pump is a good example of a weak point in the powertrain design. I predict that as 3G ages, the engine coolant pump will be added to the inverter coolant pump as items to routinely replace if the driver doesn't want to be stuck on the side of the road due to a sudden failure.

 

Pat,

You're being a little harsh.

At least Toyota removed the Fuel Tank Bladder (a constant source of aggravation) and the coolant thermos (with its pump and valve - both failure prone).

Ever since I had a catastrophic failure of a mechanical water pump (a few years ago), I have replaced water pumps every time I replace a timing belt. In my Prius (no timing belt), I replaced BOTH water pumps (not the heater or thermos) at 150k miles (I didn't think of it or I would have done it at 100k miles).

There are many components in cars that will stop you with little or no warning.

The new design of that pump is more reliable than the one in 2004-2006 Prii and should last longer.

We're talking about 100k or 150k mile intervals here. Even a $1000 maintenance item (Both pumps cost less than that) every 100k miles accounts for only $0.01 per mile.

JeffD

 

One thing that will greatly extend the life of the stock pump/belt is to loosen the belt to the point where you can manually turn the impeller pulley by hand.

This takes off the side-loading of the stock pump, which at stock belt tension is quite substantial, and adds to bearing/seal wear. This also slightly reduces belt friction and heating which (very slightly) improves mileage and increases belt life.

I suspect with this mod, I will never have to replace the belt or the pump as long as I own the car.

Of course if your pump is already weeping (sorry BritPlus), it's too late!

I'd say simply replace the stock pump and leave the belt loose as I mentioned. You likely won't have to do it again. The "hot-soak" problem is not really an issue in the Prius, as the electric heater pump keeps coolant circulating when the engine stops. The Atkinson cycle helps reduce high spot temps in the head and cylinder walls as well. While electric appeals to me too (I'm an EE also), it sounds like a big expensive hassle for no real gain.

 

If the belt is loose enough so that you can turn the pulley by hand without moving the belt, then I would say there is a reasonable chance that as the engine revs up to max speed (which could be ~5K rpm) that the belt would come off the pulleys.

 

This has never happened, and I don't think it could (unless somehow a foreign object get in there). Keep in mind it's not *that* loose! Just loose enough so there is no appreciable side load. My test is to grab the pulley and yank on it, and if I can move it a little, it's just right. The belt deflects an inch or so easily in the center.

YMMV, but it works for me!

Typically on most cars belts need to be tight as they are transmitting substantial energy to all the accessories. On the Prius the belt only drives the pump, which is an insignificant load. This is why we can get away with a much looser belt than Toyota tensions them at from the factory.

 

My hunch is a loose belt will 'age' faster, loose belts vibrate more and that can't be good. I would go with the factory specs.

On this subject, I've found my newly installed belt stretched some after driving several hours, yes checking the next day when cool. Just my advice to recheck the new belt several hours after driving. I replaced my old belt , and I haven't had to replace my water pump, owned from 106k to 190 k miles. Guess my point is , this area , belt tightness, doesn't seem to be something I need to 'adjust', something I generally like doing.

 

Figured I'd check in to see if you've worked on implementing, any updates in general and/or have observed the same 1.5L Prius C engine with the same gen 3 1.8L Prius water pump? Also, the crafty Siberians have been implementing the Prius C engines into the gen2's as I am planning to do with my recently brought home 2014 Prius C engine.