WVO boost pump? What should I use??? - PeachParts Mercedes-Benz Forum

Blevinsax · #1 08-21-2006, 10:24 PM

I just had a GreaseCar WVO system installed on my '91 350SD and although it runs GREAT on WVO when it gets running, it seems the stock fuel pump is unable to pull the WVO all the way to the engine compartment from the tank in the trunk. I spoke with my mechanic today and he was in agreement that I probably need a boost pump to help get the WVO moving, but he said that I need to find the right pump becuase he had bad experience with standard fuel boost pumps on other installations. He tried several pumps from Napa, but they only lasted a day at most, then shut down - so I need to either get the auxilliary pump available from GreaseCar or something with similar specifications.

Can anyone recommend a good pump that will help get my WVO moving so I can burn the junk up instead of buying diesel!! Besides, I have 50 gallons of the stuff sitting in my garage that needs to be used!!

Lostyankee · #2 08-22-2006, 01:01 AM

Try blending with RUG instead of throwing another mechanical gizmo on the car.

Blevinsax · #3 08-22-2006, 02:29 AM

No thanks...

I'll continue with my GreaseCar WVO setup. I'm really not very interested in putting gasoline in my diesel engine.

If you have experience with a WVO boost pump, I would appreciate a brand/model recommendation - something that has turned out to work effectively and consistently.

Thanks!

Jmana · #4 08-22-2006, 07:14 AM

I haven't heard of any of the electric pumps that actually work well for WVO. Most last a few thousand miles, tops. I have however heard of people having sucess using an oil pump to get the WVO moving. I believe they are called oil sump pumps, and you put the pump in the tank, somehow fit a rod to the pump that extends out the top of the tank, and then attach a 12v motor to that.

Jmana · #5 08-22-2006, 07:20 AM

Another thing you can try is using larger diameter fuel lines. Your stock pump should be able to pull the fuel, unless it is really thick or really dirty. Maybe your lift pump is worn out? And I think most WVO filters need to be under suction, if you pressurize one side of the filter, you will not get very good water seperation.

jshadows · #6 08-22-2006, 09:09 AM

I had problems with this too. I don't think it's an IP suction problem. It's dirty injectors.

When I first installed the kit the engine had no power under load when on VO. I put a 100 gallon treatment of Power Service Diesel clean in the diesel tank, drove it 10 miles down the road, and voila...grease ran fine. After several months I started having problems again, and this time I installed a clear filter just before the IP. This time it appeared to be VO starvation as I could watch the filter empty at high rpms. Blew compressed air through the lines and starvation problem went away. However was just having problems the other day, still no starvation at the clear filter, so I Power Service'd again, and now seems to be ok again.

One thing I am clear on now, is a WVO system is not low maintenance. You need to clean the tank from time to time, maybe blow air through the lines, and definitely run products through your injectors to clean any garbage out.

Jmana · #7 08-22-2006, 11:04 AM

If everything is hooked up right, it should be low maintenance. The only problem I've ever had is air in the lines, and it sounds to me like you may be confusing air in the lines for diry injectors. If you put that much dieselkleen in the tank it will thin the oil out and there is much less restriction, thereby less chance for air to arise. On my old car, once I had everything sealed up properly I never had any problems. Drove it for more than 20k miles with no clogged injectors or a coked up engine. If you don't have clear fuel lines, you won't know if there is air in them. A clear filter won't tell you much.

Johnt49 · #8 08-22-2006, 11:29 AM

Take a look at these:

http://www.autoperformanceengineering.com/html/6000_pump.html

Others have had good results with them. Make sure you have 3/8 line from the rear to front of car, veg oil is a lot harder to move than diesel. These pumps are designed to push rather than pull, so it needs to be mounted close to your veg oil tank. You should be able to bypass the stock lift pump & use the Walbro to feed the IP through your filters & heater. This leaves you with an unmolested diesel fuel supply circuit, should you have trouble with the veg oil system.

#9 08-22-2006, 05:28 PM

I have experienced this with my 85 300D. I have chosen to live with it for now. I am trying to figure out if it's a difference in how the engine runs or actually sluggish. It seems to be on a sedative, but smoother. I am not sure the car is actually slower. And it sounds like sedative when idling too. I am putting an injector upgrade (i.e. bigger holes, less resistance) in my VW TDI. Have not researched a similar option for Dbenzes.

Old300D · #10 08-22-2006, 06:40 PM

Even 3/8" line will be sluggish with oil that's not up to temp. At least on a 617.

Deni · #11 08-22-2006, 07:00 PM

How about looping the return before the fuel filter? The pump will have to suck less fuel, and the fuel coming from the return is already hot.

Jmana · #12 08-22-2006, 07:09 PM

I second the motion to loop the return, or do what I did and put a tee in the return and a tee in the filter outlet line, and then connect the 2 tee's together. I have noticed that the engine has a lot more pep, plus the oil gets up to temp quicker. The only downside is if you get air in your lines, you're kind of screwed.

jshadows · #13 08-22-2006, 08:06 PM

actually, I don't put the dieselkleen in my veggie line, but in the diesel tank. The diesel additives just create a liquid emulsion in the WVO...not a problem, but just doesn't mix. That's how I could only assume that the clean helped as it ran fine on veggie afterwards.

The only source of air I can see in my greasecar system is on the solenoids. Rest of system is HIH and very closed to outside elements..and if it was leaking I'd get coolant and not air

. Solenoids however would seem to be a possible source if they are faulty. Greasecar solenoids have been known to fail and a source of frustration for customers as there is no warranty that I'm aware of (though I'm not sure they fully disclaim, so UCC Article 2 might say otherwise

)

#14 08-22-2006, 10:40 PM

I've yet to get running on wvo, but thought about this. If the wvo tank is airtight, or can be modified to be so, how about a 12v air compressor to pressurize the tank? A pressure relief valve or pressure sensor hooked up to turn the compressor on+off would be necessary. I happen to have a 12v compressor, and want to build a system with what I already have.

Jmana · #15 08-22-2006, 10:55 PM

It's funny that you mention pressurizing the tank, because I thought of the same thing a couple of days ago, but unfortunately I don't think it would work, because your not just pushing fuel out of the tank, there is also fuel returning to the tank, so if I am thinking corectly pressurizing the tank will not create any extra flow at all because you'd be pushing on both lines with the same amount of pressure.
So greasecar has had problems with their valves failing? That's great to know, I just installed two of them on my car. I was really pissed when I first installed them, because the one valve was defective and had the fuel outputs backwards. So I am driving down the road and can't figure out why the fuel gauge for the main tank (where I keep my veggie) said I used half a tank in 30 miles. I even stopped to make sure I didn't blow a line in the engine, and didn't see anything so I kept going. Then I noticed the trail behind me. Stopped the car and veggie oil was pouring out of my trunk. What a friggin mess, luckily I didn't have anything in the trunk except the diesel tank, but I never did get rid of the smell. I should have made Greasecar pay to have the trunk detailed.