No need for a war. I am not interested in hiding anything as I don't have an agenda outside of contributing my experiences, warts and all.
I certainly appreciate your non biased attitude towards WVO. Your opinion would be one that I particularly value because of your extensive experience... I would certainly categorize you as someone that knew enough to accomplish success in the best way everyone knows how...
Never early switchover IMO as I have a controller that is programmed to not actually switch until the engine is up to operating temps. The change I am making is to not switch until out on the 4 lane and at light cruise speed. I did not always adhere to this in the past. So I guess it depends on your definition of early switchover. Mine just got more stringent.
I would not classify that as early switchover either. This is the practice that I have used from the start... wait to get out on the highway, make your merge, hammer down etc... etc... set the cruise and switch to oil...
I've also always purged while still on the highway instead of at idle. I never liked the idea of ever being on WVO when at idle... I don't know why, I just never did. I've burned WVO a couple times when in stop and go situations and decided to always purge long before I would see myself in that scenario.
I truly believe WVO is for long highway trips, only...
As for purge, the PD will purge very fast by design. The PD tandem pump moves fuel through the head pretty fast. With a clear return line at idle I have observed full fuel exchange in 12-13 seconds at my solenoid. Admittedly in the early days my purge was short as 30 seconds of run after the purge completed (not enough). I had changed this to a 1:45 (as a backup) and have been in the habit of purging and driving for several miles before shut down for quite some time. When my purge had been too short and I examined the piston tops 38K ago, they cleaned up with a rag and had no coking on the tops at all. Even with a much better practice of earlier purge, the current tear down showed tons of deposits on the piston tops and top of cylinder wall. I am interpreting this to mean that purging did not cause the issue specifically, but injector spray pattern loss. If anything earlier too short purges may have contributed to hastening the injector issue that lead to the ring issue. Nevertheless, my change will be to purge before hitting the off ramp from now on. Lengthening switchover and purge times is good advice and should be considered for a 'best practice' for sure.
When did you actually convert your car? I would say roughly the 60k mark? You do have to consider that 190k is a lot of miles for a car and although diesels are tough, there are components that wear out. I think WVO exacerbates this effect sooner rather than later. The problem with WVO is coking issues and polymerization. You could run sub par atomizing injectors for years and only experience worse fuel economy, smoke and poor power, but never would you experience the catastrophic issues that sub par injectors could cause while running WVO.
How tight of line, hard to tell. I won't defend WVOing with mods. I avoided stop and go driving but would run VO under most other driving conditions. How much of a problem power mods are is going to be hard to tell, mine have been in place for 90K WVO miles. More fueling can lead to higher peak temps, perhaps especially considering how most go about tuning the PDs without nozzle upgrades, increased injection duration probably didn't help. I will say that EGT's didn't increase under my most common driving conditions. So far I am not convinced the tune is the only thing that created the tipping point. I do have more PD WVO miles than most after all. Everyone will have to decide for themselves. Not tuning is probably better in the long run and might borrow some time before trouble strikes. I am a big boy and clean up my messes and am going big on the mods....
The tune if anything should increase combustion efficiency if driven by a sane individual. I don't think this added to your problem. I think power mods can help the cause if driven with some sense... It seems like most of the time you had that...
Agreed. There went 90+% of WVO users. One of many reasons why it is mostly not a good idea for most (if any?)
I agree with this 100%... One of the reasons I wrote my guide the way I did was to scare off anyone that was on the fence. You got to be smart and educated to be able to do it the best way possible.
My take on the situation has and will always be the purge. I don't think people understand the importance of not only purging but driving long after you purge... My best practice method after a purge and on diesel fuel is hammering the go pedal, 26 PSI of boost, up a long grade of hill, barking second and running up through the gears till about 65 MPH...
I do this after I have purged for 3-5 miles... that being a huge difference...
It's almost like you were never burning WVO when you do things this way... you start and stop on diesel, nothing is left to chance... When will you ever experience coking issues when your running on the highway at a consistent 2700 RPM, on boost, highest combustion efficiency... and then purge before you get off the highway... drive with some sense on diesel for about 3 or so miles and then "italian tune-up" up a long grade or down a long road... This has been preventive maintenance, so to speak... to prevent any polymerization of my injectors etc..etc...
Of course my car is different... I would guess that the injectors on a PD are even more critical that they are popping correctly because they operate at a higher fuel pressure...
