LLewandowski wrote -
"I know of at least 5 people who have converted this truck . I don't believe heat is the main issue with the vp-44"
I don't think heat is the main issue either. I don't think there is really a main issue, but a series of issues.
How do you handle the lubricity of the VP44 given some of the extremely tight manufacturing tolerances? Do any of the "additive" manufactureing companies state their additive is compatiable with VO? Veggy oil is a great lubricant . What kind of additaive ? I know veggy is under the radar and not many companys make any claims on it .
How do you handle the heat issues (what are the differences in the heat transfer rates of diesel vs VO) for heat extraction? During my researching I read your entire thread about cooling the VP44. I was worried at the time , because you actually heat veggy oil to a max of 180F before the injection pump . Facts are sketchy here , but I believe its the on-off-on-off heat cycles that are to blame for the electronics faliure and not a steady higher temp .
How do you handle the free water issues so as to minimize and mechanical damage in the high pressure side of the pump when any free water turns to super heated steam? I will be washing and vacumn drying and filtering all my oil to 1 micron . My whole system is going to be stainless steel , with tank breather that extract moisture from the aim , FASS water seperator , and a drip leg that I can drain water from the oil . Vacumn drying will also take care of suspended water in the oil that won't settle out . I'm hoping this should do . I havent seen anyone get that crazy , and thier doing ok .
How do the fluid characteristics of diesel compare with VO? The flow rates, viscosity (especially under high pressure), heat absorption (above), what is a good diesel VO mix rate (and why)? is the VO tested to a use as a fuel standard? the VO storage characteristics? Veggy is much more viscous , thats why you heat it , to lower viscosity. Oil varrys but when heated to around 300F it reaches the same viscosity . Its not a direct heat rise viscosity lowers realitionship though , so 180F gets you pretty close . I don't plan on mixing veggy , but some do , I couldnt tell you thier mixtures , but some also mix Reg unleaded gas , kero ect . I will be using a 2 tank system , one veggy one petro . I will start and stop on petro . I have my tank finished which is 14G stainless to fit behind and under a cross-over toolbox . Veggy is not recognized as a fuel . I've heard of people storing for over a year if done properly .
I would love to run VO in a Vp44, but there are a whole range of uncertainties and why the general trend seems to be toward the mechanical pumps (P7100 and earlier) with very different heat characteristics, pressure characteristics, lubrication characteristics, power characteristics, electronic control characteristics, just a whole lot fewer things to deal with. The P7100 is definatly the prefered route , but not an option for me .
Maybe "better" (VP44) is not necessarily "better". For my knowldege , which is limited , the whole vp-44 setup is better emmisions , and alot more worries .
What do some of the injection pump rebuilders have to say on this subject of running VO in the VP44? THEY are the most knowledgable people I know of that would know what the actual operational VP44 weak spots are. THEY are the ones that see the cause and effect of wrongful care and feeding of the VP44. The rest of us are just guessing (and that includes me as well).
Well I know of one instance where a guy converted his dodge , then it died . He was worried it was from the conversion and took it to the dealer . They told him to rip that off or they cant warranty it (I think they were buddies) . It was actually a pluged filter , but just tells me I'm on my own as far as warranty . But warranty is almost up anyway , and I've weighed the risks . I do know one guy who travels for work and puts 1000+ miles a week on his no major problems so far .
Bob Weis
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