The Grease Car Mod

The GreaseCar modification to my car doesn't change anything with the engine - it's a 2nd fuel tank that's heated from the waste heat of the engine (coolant).

The GreaseCar website has an excellent flash animation explaining everything.

Here's what the modification looked like once I got it back from Young Street Garage.

1) Under the hood.
The red hoses contain coolant to heat up the fuel filter assembly on the right. At the bottom, you see the two solenoids to switch diesel/veggie/diesel-backflush. You can see the VW engine cover is still there, I eventually remove it.

2) The dashboard.
An aluminium plate holding the fuel gauge and 3-way illuminated rocker switch is attached quite snugly to the bottom of the standard centre dash. Below, the ash tray is removed (we don't smoke) and the GreaseCar temperature gauge is installed.

3) In the trunk.
The spare wheel is removed, and we now carry cans of RideFlat wheel sealant in our emergency kit. I've tried to insulate the tank with foil bubble wrap. Fiberglass would just get nasty and loses its insulating properties if compressed. Notice how we don't lose any trunk space with the modification. I suggest using a end of a roll of masking tape to protect the fuel-level leads from weight of trunk items (hidden by a block of white foam in the picture below).


I found the heat of the oil to suffer in the winter. So after reading InfoPop a lot, two upgrades that should solve my problems of winter vegoil fuel heating were discovered.

1) Brazed Plate Heat Exchanger

Click to animate.

Brazed plates have more surface area than flat plates, so they can transfer heat from the coolant to the vegoil fuel better. This is the "heavy lifter" for vegoil temp. The thermal energy transferred is much greater than the GreaseCar thermal filter assembly or the PlantDrive VegTherm. But it is limited by how hot the coolant is.

The engine cover doesn't fit anymore with all the extra hoses. I didn't like it anyways.

2) PlantDrive.ca's VegTherm Mega

30cm long, 32Amp at 12V of electrical resistance heating. This sucker burns skin on contact. After the oil is heated in the trunk tank, after it's insulated in the hose-in-hose line under the car, after it's warmed up a bit by the GreaseCar thermal filter assembly, after it's raised to the same temp as the coolant by the BPHE - the VegThermMega does it's thing.

I also stopped using foil bubble wrap for insulation and moved to copper pipe foamies - they insulate way better.

As you can see, things are getting very tight. But it's still manageable, even for me.

Yesterday, my BFHE was showing temperatures of 50C (it was likely warmer, temperature sensor heat loss to ambient air temp) I turned on the VegTherm and the oil temp out the other side was 68C.

Time will tell how it does in -30C.


Jennifer J said...

Dear JL,

Today's (Dec. 3/07) The Current show was about running cars on cooking oil in an undeveloped country. The podcast isn't out yet, but it will be I will watch for it for you!

Did I tell you about the turkey vulture episode?!

knabe189 said...

I have a Jetta 2000 TDI with a greasecar system and I just got a FPHE. I'm wondering how you mounted your FPHE. I went out Friday afternoon to put it in and I couldn't figure out how to mount it. Thanks for any help you can give!


STL_Kevin said...

Where did you get the aluminum plate to mount the rocker switch and fuel gauge?

... Smells Like Fries said...

knabe189 - My mechanic tig welded it to the frame and painted it with protective paint.

stl_kevin - just scrap aluminum. Most garages will have lots of it lying around. Go ask for scraps. Or maybe a hardware store, but I doubt they carry a thick enough guage.