Smoked it after about three minutes. It worked fine for transferring oil from one drum to another, but not when I hooked it up to the 'fuge. It ran that SBC pump up to 100psi line pressure like a champ, though. Then RPMs dropped down and I smelled the stink and saw the smoke. Done... Good experiment, though. I have a 1hp 3450rpm table saw motor that I can use; it'll just take a little more rigging to get it running.
HF 1/2" Hammer drill will NOT power a SBC pumped centrifuge...
- Thread starter 8ball
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Smoky12v
Registered User
The spinner centrifuge like the pabiodiesel require 80-100psi BUT low gpm. The sbc oil pump was designed to pump 20-50 psi with much more gpm so if you try to make it to pump the spinner, the motor in the driller get loaded pretty hard IMHO.
Yeah, I'm figuring that out. The SBC pump was delivering TONS of volume for that three minutes. I hooked up my table saw motor direct drive style to the SBC pump this afternoon and it tripped the overload almost immediately. I'll give this SBC pump more try; I'll get a big pulley/sheave to mount on the SBC pump drive shaft and see if the table saw motor will turn it then. If not, I suppose I'll have to get out an old PS pump. Those have to gravity feed, which means putting a hole in the barrel down low.
Smoky12v
Registered User
You can add a bypass/regulator valve to bleed off excess pressure/flow.
Smoky12v
Registered User
Good to know what those sbc pump are capable of!
OK, strike three on the SBC pumped centrifuge. I stopped by the local hardware store and picked up a 4" diameter, 1/2" bore sheave (pulley) and mounted it on the SBC oil pump. I then connected it to my table saw motor via a belt. It ended up being about a 3:1 reduction in speed from motor (3450rpm) to the SBC pump (turning about 1000rpm). It ran fine with the bypass wide open, but as I closed the bypass to bring the pressure up on the 'fuge, the motor started to stall out. Guess I'm punching a hole in my barrel to gravity feed a PS pump.
Josh Carmack
Full Access Member
Reduce it a LOT more, that pump needs to turn 100 RPM or less to feed .92 GPM it'll output lots more presure, just needs to turn a lot slower, it's a positive displacement pump, it can easily supply the pressure, just need to give the motor enough leverage. A 3450 RPM motor is way to fast. My PS pump pumps probably 7 or 8 GPM and thats with 4:1 reduction on a motor running 1750. My driver motor is 2 speeds capable of 1050 as well, and it still outputs WAY too much volume at only 250RPM. Because the motor is partially shaded pole when it's running on low speeed it heats up a lot faster running on low speed and is only about 40% effcient so I run it on high speed, and the "throttle" valve opened about 75 percent.
i agree with Josh on this one, that is not much reduction for that fast of a motor
Josh Carmack
Full Access Member
Something else to keep in mind, HP is a measure of Power, power being an established amount of work done over time. A 1/2 HP motor running at 3450 is the same power output as a motor running 1750 at 1/2 HP. Torque is what you want in our particular application. The most torque will come from the lower rpm motor. A 3450 rpm motor is still capable of doing the same job , but you'll need a lot more reduction. 8:1 one would be a great starting point for your motor, problem is, you'll need a 2" sheave, and a 16" sheave. A double reduction will result in another 10 to 15% loss in conversion. With a positive displacement pump, speed is almost not a factor in the amount of pressure it can output. I don't know what the SBC pump's efficiency is, but I'm betting it wouldn't be less than 80%. With that said, I'll bet that pump can output the 1GPM needed to drive the fuge at around 150 to 250RPM. when I hooked my PS pump up to the fuge with no bypass it only took 150 200 rpm to feed it with the needed 85 psi. That was with a Black and Decker cordless drill in low speed with its max no load speed being 450 RPM.
Also I'm no pump expert, but I don't see why a PS pump can't draw from the top of the drum, prime it first and see what happens, it may need priming, but that goes for the SBC as well. I know the SBC may hold prime on the backside a LOT better than a PS pump, but again, my experience is lacking.
Also I'm no pump expert, but I don't see why a PS pump can't draw from the top of the drum, prime it first and see what happens, it may need priming, but that goes for the SBC as well. I know the SBC may hold prime on the backside a LOT better than a PS pump, but again, my experience is lacking.
Thanks for the info. I'm really trying to get running on the cheap, so I'm trying to make this setup work with stuff I have on hand. I have a couple of GM saginaw PS pumps from my chevy days, and those will supply the pressure needed but can't be run dry without ruining them. They won't pull suction at all since they have the reservior built in. I think a 16" sheave and/or double reduction stuff will be cost prohibitive. If the GM saginaw pumps won't work, it's off to the junk yard for a honda or VW PS pump with separate reservoir. Thanks again, the info really has helped me understand the process.
Oh, and before I punch the hole in the bottom of the barrel, I will try to see if I can get a siphon going to feed the GM PS pump. Maybe my WMO won't be too thick.
Oh, and before I punch the hole in the bottom of the barrel, I will try to see if I can get a siphon going to feed the GM PS pump. Maybe my WMO won't be too thick.
Josh Carmack
Full Access Member
Seal off the resivor and then prime it. as long as the resivor is completely sealed it should pull uphill a few feet no prob. priming it uphill may be a PITA.
If you want to stay Chevy some cameros had pumps with no reservor, that's what I used in my truck. Besides that watch pump rotation, the acura and hondas turn the oposite what other manufactures turn.
