JeffNLisa
Active member
Fortuna Wolf said:
Hi Fortuna-
Sorry I was not in this thread for a few weeks. I was just going to link to some other discussions on the Greasecar forum and the Frybrid forum. But since a fair number of people have been in this thread, I'll answer everything you ask here, and hopes that others will see it here too.
Much of the disparaging stuff about Greasecar comes from earlier versions of their system, which honestly deserved the criticism. They have improved many aspects of it. Others are still lacking, and if you have seen my posts about this, I am pretty straight about these areas. But they can be made to work correctly.
The biggest problems that I have seen with a Greasecar system can easily be rectified, and while they have not advertised it, they actually have solved some of the problems.
One of the two biggest problems that you will get over time, and what has caused the greatest amount of grief, I think, for Herm, Jason, drivebi, et al, comes from improper and/or incomplete purge of the WVO from your IP when stopping the car. How you plumb the lines and how you stick to operating procedures will solve that. Here is the best way to plumb the GC system:
Diesel tank - diesel fuel filter - supply valve Normally Open (NO)
WVO tank - WVO fuel filter - (FPHE if you have one) - supply valve Normally Closed (NC)
Supply valve Common (COM) - LP/IP - Return Valve Common (COM)
Return valve NO - to diesel tank
Return Valve NC - to tee in WVO line before WVO fuel filter
I am not a fan of looped return, but it does put less stress on your IP. And plumbed this way, the only drawback is potential for an air bubble to get trapped in the loop. This plumbing does NOT backflush your WVO filter with diesel, and as long as the filter is adequately heated, which GC is, that is totally not needed. Some other loop plumbing methods cannot purge completely, and many systems are incorrectly plumbed. If you plumb the way I showed, then at purge, the WVO is sent down the WVO supply line back to the WVO tank, and you MUST time it to see how long a purge cycle is needed to get the WVO past the return valve and all replaced with diesel.
The way to do this is with a sight glass. Use a piece of clear tubing and put it in right after the return valve in the VO return line. After testing, take the clear line out. From my experience, you need to put it vertical, not horizontal, and with the fuel flowing down, not up. This will make it the easiest to see the change in the appearance of the fuel. You either need dyed diesel or warm WVO in the WVO tank. You can get dye to dye diesel a dark color and put that in the WVO tank (I've found that red diesel is not dark enough to be accurate), or if you use WVO, you need to drive the car on DIESEL ONLY until it's fully warmed up before testing this, because you DON'T want cold VO in there. I prefer the latter method.
With the vehicle idling, you switch back and forth between WVO and purge. BE VERY CAREFUL NOT TO LAND ON DIESEL DURING THIS TEST. When you switch to WVO, it will take a minute or so for the fuel in the loop to become mostly WVO, and you will see the change in the look of the flow in the sight glass as it becomes more WVO (the diesel flows in a "jittery" flow, the WVO flows in a more straight flow). When you see it, you will know it. Once you can be sure it's WVO, then switch to purge and start your stopwatch (or carefully note the second hand on your wristwatch. Then walk back around to look at the sight glass, and look until the flow has completely changed to the diesel, and mark the time. On an 02 TDI, if your lines between the IP and valves are not abnormally long, this should take about 12-15 seconds, but each car will vary. I urge you to do the test multiple times. The first time we did it, we repeated it TEN times to be SURE. Just switch to WVO mode, let it idle a minute or so til it's back to WVO in the glass, and then switch back to purge and time it again.
Once you know the time, I would add about 5-10 seconds to that for my regular purge time, because when you see the fuel completely changed to diesel, there will still be trace amounts of WVO blended with it, which will gradually build up in your diesel tank. So let's say you timed 13 seconds, and you add 7, then that would indicate you should purge for 20 seconds if you purge at idle. Once you know the times and have purged correctly, then you can switch back to diesel.
Now once the IP is purged of WVO, there will still be some unused WVO in the injectors themselves. If you will not be starting the vehicle for an hour or more, you want to let it idle for another 20 seconds or so to finish burning the WVO out of the injectors, leaving only diesel in them.
If you purge while you are still a block or so from the house, while the motor is driving, the purge time can thoretically be shortened to about half (because at 2300 rpm the pump is passing the fuel thru a lot faster than at 800 rpm). But since there is no way to see the sight glass while driving to test it, I wouldn't shorten it more than a few seconds. All that means is a few more ounces of diesel in your WVO, which hurts nothing and is cheap insurance to protect your TDI.
The other biggest problems will come from if you switchover too soon, before the engine is hot enough, and/or more importantly, before the VO is hot enough. The GC system will get you good and hot, but it does take longer than in a Frybrid system.
If you haven't yet installed it, I would recommend you get some aluminum tube to use in your HIH instead of the PEX tube that comes with it. Copper will do fine but is harder to work with, and *can* be susceptible to cracking inside you HIH. Aluminum does not do this. You can get the aluminum tubing here
http://www.aircraftspruce.com/catal...03versatube.php
or from McMaster Carr, part #5177K15 will take you to the page, and you can select the size that matches you PEX there.
AircraftSpruce give a 20% discount on a 50 foot roll, and then you'll have enough in case you want to also put an aluminum line in the coolant return hose from the tank to make another HIH for a WVO fuel return, that you can plumb later, either manually, or with a third solenoid valve (which not required, but is a good idea).
After changing to aluminum tubing, the heat on the filter is adequate if not terrific, and if you already got one of Omar's FPHEs you will have all the heat you need.
Put the FPHE right after the outlet of the filter, and before the switch valve. Plump so the coolant goes into the FPHE first, then thru the filter, then to the HIH to the tank.
I also cannot stress enough how important a fuel temp gauge and a fuel vacuum gauge are. I don't use in my car, but here do as I say, not as I do. The gauges will tell you immediately and constantly if you have adequate heat and/or if the IP is having to pull too hard to get fuel (which is then usually an indicator of a plugging fuel filter, or air leak in the lines).
It bears mention to be CERTAIN you tighten the flare fittings in the tank correctly. If you get them wrong, or under or over tighten them, they will leak coolant into your WVO fuel, and THAT will be catastrophic if any big slugs of coolant get into your IP. I wish GC would re-design that part, but they have had great success with it when it's done correctly, just make sure you don't do that part wrong!!
Other things I've seen with a GC system are bothersome, but not catastrophic.
Unless they have changed it, the access hatch is attached with sheet metal screws, which can easily strip, leaving the gasket loose, and resulting in some fuel weeping around the gasket. Some sealant solves this issue, but be aware of it.
Some have a fuel tank cap designed to vent thru the cap, and some of these will work great on a fuel of consistent viscosity like diesel, but on a sticky fuel of varying viscosity, like WVO, they will stick and not vent. Then you get suction in the tank. which will cause it to pull in. Then with the fuel weeping around the gasket, you will get little puddles of WVO on top of the tank, and when you open the cap it will "whoosh" air in, popping up the top of the tank, and splattering WVO all over your trunk.
This can be solved if you go to any tire store and get a new rubber tire valve, and remove the stem. Open the access hatch, drill a hole the correct size in the top of your tank (taking care not to let any of the aluminum shavings fall in the tank), and from the inside of the tank, pull the valve in with a pair of pliers so it "snaps" into the hole, exactly the way they snap them into the wheel at the tire shop. Attach a piece of rubber fuel line to that valve with a hose clamp, and you now have a perfect tank vent. I recommend running that over to a quart size Canola bottle and feeding it snugly into a hole in the lid and down to the bottom of the bottle, and then feed another piece snugly into another hole in the lid, just in about an inch or so, and vent that under the car. Now you have an overflow bottle, which will get a surprising amount of WVO in it, but it won't drip under the car and splash on the back of your car. And if the one hose goes all the way to the bottom, later the vacumm created in the tank by fuel being used will pull that overflow VO back into the tank.
Some foam pipe insulation to wrap the lines is always a good thing. It will help you switchover again faster after short-medium length shutdowns.
Then, the only thing you need to do is PRACTICE PROPER PROCEDURES!!!!
We are human, and occasionally you will flip the switch back to diesel instead of to purge. It happens, and sooner or later it will happen to you. To help alleviate problems if you get some cross-contamination, you can drive your diesel tank down to way in the red zone before refilling it, and this will HELP get out any small amounts of WVO that get in the diesel tank.
Different types of WVO will cause different problems in the diesel.
If you do not de-water it well, then more FFAs will stay in the VO, and if you have appreciable amounts of this in your diesel, it will dissolve and not clog anything, but will cause "fruit-roll-up" or "chicken-skin" to form in your IP, and this is NOT good!! I'll add a brief talk about de-watering in a moment.
If you use any Partially Hydrogenated shortening or any tallow (or if the restaurant cooks a lot of meats that leave animal fat in the VO), these things will melt fine in the Greaecar system, and burn just like any other VO in the motor. But if you get cross-contamination of this stuff in the diesel, the diesel cools it and cold it will make small blobs of solids that will plug up the diesel lines and the diesel filter. And these solids take a LONG time to dissolve in apassing flow of diesel, so trace amounts can go undetected, and eventually wash away. But large amounts will clog you.
So be VERY careful not to forget to purge correctly!!
As to filtering and de-watering:
2 empty drums to settle in is a good thing if you have the space. Time and temperature are your friends. The longer it can settle, and the closer you keep it to 90-100*F, the more stuff wil lsettle to the bottom. But pull from a few inches below the top, and go down with the level. Always pull off the top.
The settling of unfiltered oil is good, but you won't get the best settling until you have filtered to somewhere between 15 and about 80 microns. Larger stuff tends to inhibit settling, and smaller than 15 micron tends to not settle as well. Some cotton cloth will accomplish this perfectly, and what I use for that is blue jean. A jean leg can be made into a sock filter real easy, and while not reliable for finished fuel, for pre-pre-filter they are perfect. They are about 15-30 micron.
Then once you have pulled from the top of the settling barrels, thru the cotton cloth, NOW it's VERY IMPORTANT to treat this next step correctly.
Here, you have WVO that is filtered to around 30 micron. At that level of filtration, it will settle PERFECTLY if you can keep it around 90-100*F for a 8-12 hours. Nearly all of the water and any other sediment will fall to the bottom. If you can't keep it consistent at 90-100, then heat it to about 140 or so in an insulated barrel, and let it cool overnight. As it drops past 90-100, you'll get the same settling effect.
Then you have well settled and de-watered WVO on the top of that barrel. It is safe to draw the top 70% off of this. Then that goes thru an automotive fuel filter, to filter it below 10 microns, and you have perfect fuel.
The most concise way to make that system is with Dana Linscott's "Simple Handpump Prefilter Unit" that he sells the complete plans to make it on his website at www.vegoilconversions.netfirms.com and look for the "How To" files. One of the best $30 I ever spent.
If you want to then store that fuel, I have never needed any biocide, but it doesn't hurt. What you DEFINITELY want to do though, is fill the storage container FULL, and SEAL it so it is airtight. Clean vegoil cubies are great for this. Ifthere is no air, nothing can grow. I have used VO stored this way for 6 months with no issues, and Dana has used VO stored over 2 years this way with no issues.
I do have a short-term storage tank I use, and if the fuel will be used within a few weeks, that is fine. But if you do this, unless it is filled FULL, and SEALED TIGHT, do not put that VO straight into the car's tank without passing it thru a filter again on the way into the tank. I have a pump on my storage tank, and I just have an automotive fuel filter in the line after that pump, so any stuff that may have gotten into the VO will be filtered out on its way to the car's tank.
But if you pump from the Dana filter barrel straight into the car's tank, or into clean cubies that you fill full and seal, you don't need anymore than the one filtering barrel.
DieselBurps on the Frybrid forum uses multiple barrels, and settles and pulls the top 70% or so off into another barrel, thru as many cycles as he has barrels to put them. He refers to that as "racking" from the beer brewing industry, that's how they refine it. But he has space for a dozen barrels, and he lives in Florida where its warm year-round, and usually needs no electricity to do this.
I use a water heater element in my Dana filter barrel. It stays at 90-100*F 24/7, all the time. It uses about $5 a month worth of electricity. Maybe $10. Electricity is more expensive here in the summer, but the barrel uses almost none in the summer. In the winter when it uses a little more, electricity is cheaper.
Since the 20th was this past weekend, I hope you got to meet some other WVO users. Regardless, if you look on the Frybrid or Greasecar forums, GolfTDI and HJAlbert both post, and they live in NC. Both have been very helpful to me and to others, and may be willing to give you some help.
Installing the kit is very straightforward, and there are many pictures of different TDI installs on the Frybrid forum, Although a Frybrid works a little different than a Greasecar, the important details will be apparent.
If you've decided to grease, just do it right and best of success!!
Jeff
