HP/KW required to turn the pump

dalek · Post by **dalek** » Sun Jul 12, 2009 8:46 am

Odd question: how much power is it needed to turn the fuel pump?

82vdub · Post by **82vdub** » Sun Jul 12, 2009 3:15 pm

A fuel pump on a gas engine, or an injection pump on a diesel engine?

dalek · Post by **dalek** » Sun Jul 12, 2009 3:37 pm

Well, I did not know I this forum would also take gasoline engine questions, specially since it said it was more for pre-TDI cars. That is really nice to know!

However, I had a Bosch VE series pump in mind. If you run gasoline on it too, you sure are way braver than me!

libbybapa · Post by **libbybapa** » Sun Jul 12, 2009 3:43 pm

I don't know the HP required and have never seen it listed anywhere. Do you want to know the max or the average? The HP required at full pedal will be significantly higher than idle. Additionally, the HP required for a pump with a larger plunger will also be greater.

dalek · Post by **dalek** » Sun Jul 12, 2009 4:04 pm

My problem is that I want to build a bench tester for the pump and need to figure out which electric motor and pulley setup I will need.

libbybapa · Post by **libbybapa** » Sun Jul 12, 2009 5:06 pm

Be sure to let me know when you figure it out. I'd also be interested in seeing details on the bench tester.

82vdub · Post by **82vdub** » Sun Jul 12, 2009 10:03 pm

This particular forum that you posted your question is for general VW questions, gas or diesel.

As for figuring out to determine what HP you need to spin the pump, maybe a little internet searching for some Bosch IP testing equipment may yield a HP size for testing equipment, or a specific model number and a sales company that a phone call could have someone tell you the electrical charasteristics for that particular piece of equipment.

Vincent Waldon · Post by **Vincent Waldon** » Sun Jul 12, 2009 10:29 pm

I've been giving some thought to a test bench also and this question has come up in my mind as well.

I've seen people spin 'em with reasonably-sized electric drill... so that's where I was going to start. Per Andrew's point, the power required at idle is not going to be what full throttle will require, but the "test bench in my mind" is more about confirming proper leak-free operation, so I'm not thinking I'll need the full power.

I'll have to go check... there's a reasonable chance one of the 2 original papers on the design of the VW diesel engine lists losses due to the pump.

libbybapa · Post by **libbybapa** » Mon Jul 13, 2009 12:10 am

I have also given thought to building a test bench, but would fit the injectors and test the flow rate. I actually have a wood flooring drum sander (throw-back from my wood flooring business) which has a 220V 3 HP (very high torque) motor with a cogged drive pulley that has two different sized sprockets for two different speeds. I've thought that coupled with my pulse adapter, advance equipped timing light, gauge equipped air pump for sending pressure to the aneroid, graduated cylinder and stopwatch I'd be in business.

Quantum-man · Post by **Quantum-man** » Mon Jul 13, 2009 4:18 am

You could work it out using radius' leverages cosines etc, but why not get a spare pump, stick it in a bench vise put on lines and a set of injectors...
Fill up pump, energise the solenoid, wrap sea fishing line round the sprocket, attach an electronic fish balance, and pull. Do it for several different [calibrated] sets of injectors. Plot the graph. Take your infra red or other tach reader, and note rpm....

libbybapa · Post by **libbybapa** » Mon Jul 13, 2009 11:27 am

The HP requirement will also vary with RPM (added internal pressure and drag on the vane pump).

tawney · Post by **tawney** » Tue Jul 14, 2009 9:08 pm

I've turned several pumps with a variable speed electric drill: 7 amps with low gearing for a max rpm of 900. My laser photo tach indicated that it was turning right close to 900 when pumping fuel through the pump with the drill maxed out. So, very little loss of rpm with 770 watts at that slow speed. You would probably want to turn at around 250 rpm up to 2500 rpm to test it through the full range of engine rpm, so maybe plan for 1200 watts? There's more to it than just that, though, because you'll need a good bit of torque just to get it started turning. The drill I used was electronic variable speed which can provide the maximum wattage even at slow rpms.

Post pictures when you get it up and running.

Steve

libbybapa · Post by **libbybapa** » Tue Jul 14, 2009 11:27 pm

Yes, I've turned pumps with a drill as well, but never with the injectors installed and fuel being pushed. I imagine the HP requirement is considerably more under those circumstances.

Vincent Waldon · Post by **Vincent Waldon** » Wed Jul 15, 2009 12:23 am

The test bench Giles uses (as per his Youtube videos) has a rather large motor... admittedly it looks like it probably can handle everything up to a D9 pump, but I'd bet that with injectors installed it would take a bit of power.... my guess is that Andrew's motor will handle it.

hagar · Post by **hagar** » Wed Jul 15, 2009 8:25 am

dalek : please enter your location on profile

hagar.

Former VWDieselParts.com Forum

HP/KW required to turn the pump

HP/KW required to turn the pump

H P to drive V E Pump.