reversed water pump motor

[whateg0]

I have a bit of a dilemma. A minor one, really. But it's something that I've been thinking about a lot lately. As many of you know, I come up with some hare-brained ideas sometimes, but they're fun to explore, so how 'bout this one.

On my project truck, I'm putting the motor behind the cab. To gain sufficient airflow across the radiator, I want to go ahead and put the it up front. Unfortunately, this leaves quite a distance between the motor and the radiator. Plumbing isn't an issue, but moving air while at a standstill is. So, the obvious solution is to use an electric fan. I HATE ELECTRIC FAN NOISE ON OLD VEHICLES! It just seems so out of place.

So, I had thought about a jackshaft, but that would have to be balanced and fairly stiff (think driveshaft) to cover that distance. Jackshaft is out.

Next idea - hydraulic motor. Seems simple enough. Plumb it into the power steering and as long as the motor's running, so is the motor, and so is the fan.

New idea, that seems perfect - hydraulic motor powered by water. This seems great at a couple of levels. First, the water is already there. Except that I don't think it'd be efficient enough, I could just take a water pump and run the water through it. So, the motor would have to be more efficient at turning the flowing water's energy into rotational energy to drive the fan. Second plus, the motor only does work when it's really needed. Well, that's not entirely true. It will turn the fan whenever the water is flowing, so it will be spinning even when going down the road, but then again, so is every other mechanically driven fan. Here's the cool (no pun intended) part. If the vehicle is sitting still, and the water isn't yet warm, so the thermostat isn't open yet, there's no water flowing. No water flow -> no rotation!

It's just a fart in the wind, but has anybody thought of this? And more importantly, how practical would it be to implement on my truck?

Dave

[hankj]

Dave,

Stuff that comes to mind:

What is the pressure and volume of the coolant flow when the thermostat opens. At idle? At 3K RPM? Is it sufficient to run the watermotor?

Can the watermotor take the heat of the coolant?

Most watermotor applications I've seen, like ringing the bell on a fire sprinkler system, need 60 PSI + to turn, and run slow.

Hydraulic motors, on the other hand, need a high-pressure fluid source.

I dunno.....you still will get fan noise (if it can be made to work).

I'd lean toward the DC motor and thermo.

Hank

Hank

[whateg0]

Thanks Hank! The pressure and volume are definitely things to consider, and you're right - they may both be insufficient.

The fan noise in itself isn't such a bad thing. I think what makes it maybe more noticable than that of a belt driven fan is that, because its speed doesn't vary with the speed of the motor, it's relative loudness when the motor is idling is much higher. Anyway, when a motor is sitting there rumbling at idle and it's all of a sudden interrupted by a loud fan kicking on, it bugs me.

Well, it was a thought anyway.

Dave

[1990notch]

Dave,

I'm not sure what electric fan you're using, but the fans from a Ford Taurus work really well and pull a lot of air. They're cheap at the wrecking yards too.

I use a Taurus fan with a fan controller like this one:

http://www.dccontrol.com/fancontrol.htm

It's pretty quiet with that controller since it usually runs at about 50% at idle.

It uses PWM to control the fan speed, so it doesn't kick on & off like a relay would.

[whateg0]

Notch, that sounds like it might work. I really haven't done much with the truck except move the cab out of the way a few times. Other stuff keeps getting higher priority. I have moved my goals out a little, so by September this year, I would like to have a floor in the cab. We'll see how that goes... You have a good point about the fan speed. I know that on some of the test equipment we build, we lower the fan speed to lower the noise, so even if it takes 2 fans running at half speed, we can move enough air and it's much quieter than 1 fan at full speed. I'll give that some thought.

Dave

[Brasco]

my 2004 Jeep with the 4.7 L engine has a hydraulic fan driven from the power
steering pump. You can buy water pumps that go inline with the radiator hose. Boats and Street Rods use 'em. It's electric but no noise. It can push enough water also.

[COMP]

my 2004 Jeep with the 4.7 L engine has a hydraulic fan driven from the power
steering pump. You can buy water pumps that go inline with the radiator hose. Boats and Street Rods use 'em. It's electric but no noise. It can push enough water also.

what model you have ??

[whateg0]

Hmm... Guess I need to look into that. I'm not too worried about the water pump itself. It'll mount at the motor and I'll plumb it to the radiator. It's just the fan that I am looking into.

Thanks!
Dave

[vicegrip]

Fords to 1968, Chev's & Dodges another couple years.
The whole schmutz was in a box between the seats.
Radiator too!
I never remember any overheating problems.
1964 Ford, made several trips across the desert in summer.

There was a sheet-metal shroud to take the air to the radiator.

If your fan-shroud has improved fit.....to maximize "pulling"
the air thru the radiator.....it should work fine.

vg

[vicegrip]

Memory lane, will do that.
Those were so fun to drive.
You could see the road right under your nose.
Stearing was right under your keaster.

No protection though.
My dad lost a knee-cap,
in an accident.

I bought one in 78 for 35 bucks.....
and road it with dune-buggies.

vg

[whateg0]

my 2004 Jeep with the 4.7 L engine has a hydraulic fan driven from the power
steering pump. You can buy water pumps that go inline with the radiator hose. Boats and Street Rods use 'em. It's electric but no noise. It can push enough water also.

This seems interesting, but I haven't really found much info on it so far. I did a brief search this morning and didn't find any pics yet. For others interested, here is what Allpar.com had to say about it...

"In order to improve fuel economy, the new engine features a patented hybrid cooling fan system that combines in-line electric and engine-driven fans. This system allows the engine fan to idle at a very low speed (250-300 rpm. vs. the typical 650-700 rpm.), decreasing noise and vibration at idle and low speeds. The newly designed cooling system, with a high efficiency water pump and a secondary thermostat control, reduces power consumption by 12 percent (6 bhp/4.5 kW)."

Dave