Author Topic: VW/Audi 1;9 & 2:5 TDIs.  (Read 19576 times)

Jhanananda

  • Administrator
  • Hero Member
  • *****
  • Posts: 2083
  • I blend waste oils with solvents
    • Beyond Biodiesel
Re: VW/Audi 1;9 & 2:5 TDIs.
« Reply #45 on: June 18, 2016, 05:36:46 AM »
Here is a interesting comment on my YouTube channel from someone who was experimenting with an 85/15 SVO/gasoline blend.
Quote from: wmrstafford
Hi Jeffrey. I've actually read through this entire comments section throughout it's 5 years running before posting. First of all I love your efforts to help people reduce fuel costs so many thanks for your valuable information. Anyway... I have a 1.9TDi Galaxy. I decided I would first try a blend using SVO (shop bought Rapeseed veg oil) before starting to filter blends. I ran through 20 litres of an approximate mix of 85/15 as I was worried about the strong smell of gasoline and stopped there. Also as it is new oil it didn't look like it needed any more thinning. I poured it into my tank which probably still held a small reserve of pump diesel (it was below the red on my fuel guage). No problems at all, it started and ran as good as ever. This time when the tank got really low, I put in another SVO mix at 85/15. Obviously at this point now there couldn't be much actual pump diesel in the tank. At first it was okay, but has now started becoming difficult to start (taking several seconds) and produces a bit of white smoke from the exhaust for just the first few revs. After that I'm still running as fine as ever. This is mainly from cold although still the occassional tricky start even when hot (but not every time). I value your opinion on this subject more than any other I have read on the internet, so would be grateful if you would hazard a guess at my problem? Oh, for the record I had one really difficult start when hot, and the worry made me put 10 litres of pump diesel into the tank (making it around 33% diesel) which seemed to help a little but I'm still getting rough starts with white smoke. Once running though the car still flies, excellent acceleration, excellent top speeds, no smoke etc. Every bit as good as when on pump diesel if not better. Thanks for your time to read (and hopefully respond). :)

My reply was:

Thank-you for posting your results with an 85/15 SVO/gasoline blend on a 1.9TDi Galaxy.

1) First suggestions is no matter whether you are blending with new or used vegetable oil, one must always blend vegetable oils with petroleum distillates outside of the fuel tank, allow the blend to settle for at least 48 hours, and preferably two weeks.

2) Then be very good at removing any precipitates.

3) Then assure that the specific gravity of your blend is uniform from top to bottom in your settling tank

4) Then filter the blend down to 1-2microns into the fuel tank.

Essentially your observed problem is you did not put enough gasoline into the blend. I have found that gasoline at only 15% with vegetable oil is inadequate.

I have also made some improvements in the vegie blend. I now first blend vegetable oil with diesel fuel at 80/20, then leave it to settle for at least 1 week. Then I carefully remove the translucent blend from its sediments, then blend it with gasoline at 20%. I have found this new blend works excellently in my engine, and expect that it will work better on any diesel engine.
I have run various blends of waste oils and unleaded gasoline since Feb, 2007 in a 1983 Chevy G-20 van with a 6.2L diesel V-8 engine, with a Stanadyne Rotary DB2 IP. I have started the engine with no difficulty on an 80/20 (WVO/gas) blend down to 3F (-16c).  I now run 60/20/20 (WVO/diesel/gas)