Well, Corpsie, a translucent WMO blend can be made without WVO by using acetone as the primary solvent for the WMO, but, if you can get WVO free, as I can, then blending WVO at 50% with WMO will make the resulting blend translucent at no cost; however, as you pointed out, just making a translucent WMO blend does not mean that it will not react with an existing, or future, WVO blend. However, it just occurred to me that if I increased the content of acetone in the translucent WMO/WVO blend that perhaps there would be no more reactions. I will give that a try in the 50 gallons of translucent WMO blend that has been settling for a few weeks to see what happens.
Here is the sequence of work that led up to the coked injectors I replaced with clean ones yesterday:
Wednesday 03-28-2012 Back-flushed fuel line and filters; Remove and inspect fuel line y-trap; Re-Filtering blend into fuel cans and centrifuged the fuel 3x.
Thursday 04-05-2012, Replaced the injectors with a clean rebuilt set
Saturday 04-07-2012, Dropped fuel tank and scrubbed it out.
Monday 04-09-2012 Filtered 30 gallons of translucent WMO/WVO fuel blend into the fuel tank. The blend was 40%WMO/40%WVO/18%gasoline and 2%acetone. It had been settling for 2 months.
Monday 04-16-2012, noticed increasing signs of injector coking. I increased the gasoline content in the current WMO/WVO blend by 10% from 20% to 30%. Noticed the engine ran much better, lowered emissions and greater performance, which continued.
Wednesday 04-25-2012, engine was still starting well and running well, but had hot restart problem, so I replaced the injectors for a clean set.
Upon inspection I found the pulled set of injectors coked with a black crust-like coating. It was also noted that the injectors were not as heavily coked as in the past; and there were locations where the crust had fallen away on several of the injectors. I also picked at the crust with an Exacto knife blade and found portions of the crust fell off easily, which was not like any previous coked injector I had inspected from my previous experiments.
a coked injector removed yesterday
an injector from the same set at 200x
The driving conditions were similar to past conditions of driving around town short distances for shopping and work, etc.
1) The translucent fuel blend of 40%WMO/40%WVO/18%gasoline and 2%acetone made on Monday 04-09-2012 only ran for 10 days before coking was evident. A previous such blend ran for 2 months before coking was evident. This suggests that there might have been something in the WMO that was no in the previous batch of WMO that caused the coking. There might have been gear oil, or grease in the batch, which could have contributed to the coking.
2) Increasing the gasoline content by 10% from 20% to 30% seemed to halt any further coking. The chipping away of the coke crust suggests that the increased gasoline content might have worked to remove some of the coke that was on the injectors. It might be worth increasing the gasoline content at the first signs of coking, instead of waiting until I had a hot starting problem; and running increased gasoline content for a longer period, or do some high RPM runs, on the increased gasoline content to burn off the coke.
3) I will continue running this current blend containing 30% gasoline, with a clean set of injectors, and the current driving conditions for the next two weeks, to see if the injectors coke up again. If the injectors run fine through the rest of this blend, then I will introduce a new similar blend with gasoline at 30% and acetone at 5%.