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View Full Version : Diesel & WVO % for 1HDFTE toyota



mikey
4th January 2013, 09:52 AM
Hi what is the suggested max safe combo for the above engine? Is 50% OK? I'm hoping to hear of success stories for this engine (or otherwise :eek:) re blend or twin tank advice before proceeding.

Tim-HJ61
5th January 2013, 02:24 AM
Hi Mikey,, %%%

The issues you will have to manage with this engine is the same with all DI engines - your injectors.

The injectors on a DI have five or more tiny tiny holes that lead from a gallery in the tip of the injector. At each firing, fuel is forced under pressure out the hole and atomised. Once atomised, it burns very quickly and provides the power. You probably know all this, sorry, not meaning to tell you how to suck eggs.

The risk you must manage with running a DI on any blend of WVO, is those tiny galleries and hole blocking with either oxidised or polymerised WVO. Once the injector fails to spray in a nice even mist, it will spray in a jet, directly onto the cylinder walls. There it will not burn, it will run down the walls of the cylinder and get caught in the compression rings. There it will get hot and carbonise, like the sticky black stuff on a BBQ. This will lead to sticky rings, increased wear on the bore and early engine failure. I have seen a DI piston, and engine, with completely clogged rings after 15,000km from a rebuild due to the owner lending the vehicle out and it wasn't purged properly. Outcome was one destroyed 1HDT engine, needing another rebuild.

How close you want to go to risking this happen is rather like a piece of string. It's not just about figuring out viscosity, it's about determining how much polymerisation, clogging or other bad things are happening inside the chambers inside your injectors. This is not easy to see, nor to predict.

Hence the recommendations always are for a DI to have a full two tank setup with full purge. IIRC, I recall something like a 15% - 20% blend of WVO in Diesel to be the max for a DI. I recall running my 12HT on a blend such as this many years ago when I was starting out with no apparent problems.

It wasn't long however, before I moved to a full two tank and have much more confidence in knowing what is happening.

If you wanted to do some tests, you could make up small quantities of various blends, then leave say 5mls of each in small containers on the BBQ or kitchen stove and keep them hot for a while, then let them cool and see what happens. The safe blend COULD be the one that shows not signs of thickening or reacting to the air by drying out.

Talk of blends in DI is highly speculative. Two tank is the safest. It's not the blend you use to run the vehicle on, it's the blend that is in the injectors on shut down and start up that is the critical issue. Once the engine is a operating temperature, you can run 100% WVO, or a 20% blend in a standard DI, it's just the need to take exceptional care of those injectors by not leaving stuff that goes gluggy that is the challenge.

Tim

tbird650
5th January 2013, 09:14 AM
Mikey, A pic of the IP, etc might be helpful while we wrestle with the idea of adapting for wvo. You'll be somewhat of a pioneer with the knowhow being invaluable to those that follow. There was talk of a particular sensor that caused issues, I think it was a copper alloy reacting with veg acids. The thought was to study the sensor and find out amongst other things what signal it sends to the ECU. It's possibly a 0-5v signal as so many of these are. In which case you may be able to replicate the signal by other means like with a resistor for example. Another thought was to use petrol to blend with as you'll be able to mimic exactly the viscosity of normal diesel unlike using diesel thin with, where you'd never achieve the viscosity target. Startup and shutdown on diesel might still be the go even so.

Matt
6th January 2013, 09:53 AM
Bio is fine in this engine, WVO is a whole new dimension. Be warned B100 will remove the coatings on parts in the fuel tank which will give problems. In my experience it can also lead to the tankl lining being strippd off (Zinc?) forming a sand like deposit. Oil with its acid content may do similarly, I would be very concerned with oil gumming injectors. I have run B100 in th 1HDFT and HDFTE and these are some of my learnings.

markfetterplace
6th December 2013, 01:25 PM
Just wondering the same thing and found this thread. Thanks Tim, great explanation.
Anybody know anybody who does 2 tank set ups for a living in the far east? Say on a Land Rover Freelander?