Keep glowplugs on for longer?

[v8volvo]

Sorry your PM didn't come through -- I needed to delete some messages.

My concern was not about the hunting per se. A hunting idle is not a problem really in and of itself, it is more that it's a sign of some other problem occurring. If veg were not in the equation and a car was experiencing hunting after a cold start, I would want to check out a handful of things to make sure one of them wasn't off kilter: static cam and IP timing, valve clearances, cold start device function, air leaks into fuel system, fuel filter restriction, and, if all of those checked out OK, injector nozzle condition and engine compression. It sounds like you have addressed most of those, and your engine starts easily and evenly on 100% diesel, right?

Since you are introducing VO as an additional factor, my recommendation was to use your ear as a guide for what blend percentages were making the engine happy or unhappy. Hunting is a sign that it is not happy, since it (along with other warning signs you are probably seeing such as smoke and noisy running) is telling you that your fuel is not burning well. Poor combustion is what leads to crankcase oil contamination, ring damage, cylinder glazing, etc. So it is not the hunting itself that I would worry about leading to worse things, but rather, the factor that is causing the hunting symptom *also* causing other damage down the road.

If you are running veg in high percentages -- especially if you are doing it in the winter without heating the fuel -- I strongly recommend that you change the oil very, very often, much more often than every 5k. You are likely experiencing a fairly high rate of oil contamination and you do not want to allow it to get to the point of polymerization, since that will be the beginning of the end for the engine, which you have put so much work/money/love into.

In most normal cases I strongly recommend 5W40 full synthetic changed every 5k, but in your case, for cost reasons, sticking with semi-sym and changing it every 2-3k would probably be fine. Unless you are performing used oil analysis to ensure that it is OK for your situation, I think that 5k-mile oil change intervals with unheated veg blend fuel is probably pushing it.

I never heard before about water injection helping keep things clean when using VO, but it makes sense. I will be interested to hear how it works for you.

[ian2000t]

Will keep a look out for cheap oil - the last lot was from Asda, about £5 for 5 ltrs of semi synth 5/30 and try and change as frequently as possible. And as I said before I'll run some more BC109 through it before I drop the oil every other change.

I have just added last night a HIH (hose in hose) heat exchanger. Not running my fuel line through it yet, but once I know it's not leaking coolant anywhere and it's getting warm, I will do. Not the most effective Heat Exhanger but simple, cheap and puts the IP under least strain lifting the fuel from the tank. Obviously it will take a while for this to heat the oil up as it relies on coolant.

Think I have all the bits I need for Water Injection now, just testing it off the car first - once I'm happy then I will install it and see how it goes. Here's the thread on the Veg forum about it. They were injecting pre-turbo to start with (just to test it's afectiveness) which isn't a long-term option as it will wear the turbo quickly.

http://www.vegetableoildiesel.co.uk/...ge=1#pid160964

[v8volvo]

If you are concerned about overworking the injection pump pulling fuel from the tank, heat is the #1 thing to add, but you may also want to install a small low-pressure electric lift pump in line as well.

[Volvoist]

Originally Posted by v8volvo

Let me be clear -- running veg in your mix without a heated fuel system, at a high enough percentage to affect starting, is asking for trouble. Running small enough quantities that it does not affect engine operation -- small enough quantities that you really think of the veg as an additive, not a significant component of your fuel) you can get away with OK, though you will go through fuel filters at 3 or 4 times the rate you normally would, especially in colder weather when there is some precipitate drop-out from the unheated veg, which cuts into your savings a bit. However, running 50-60% without a heated fuel system is a sure recipe for engine and fuel system destruction, landing you with a dead motor and a big bill, at which point the idea of savings from running cheap fuel starts to sound a little silly......

What exactly can happen? I am wondering if this led to my destroyed GP's and motor in my 84. I was running 100% biodiesel, already processed from a local biofuels company. I don't want to trash another motor if this was the reason. I am also running it in my wifes Jeep Liberty CRD (though not at 100% usually) and around 40% in my home furnace...

[Jason]

What kind of GPs? Anything other than Bosch is probably junk, and even some Bosch plugs haven't lasted me very long. Seems kind of hit and miss. I replaced some of the plugs in my old engine a couple times within a couple years, while the set i have now in the new engine has been in for over a year and they are all fine.

jason

[Volvoist]

I have/had Bosch 80010's. They are the only plugs I have ever used in a D24/D24T and have never ever had any issues in the past...

[ian2000t]

It "could" have contributed. Well made bio should be usable in any car just like pump diesel.

But I think in the winter it probably is still a bit thicker than pump diesel, meaning your injectors may not "mist" aswell which could lead to issues. Another thing is generally you need to run a little more advance with bio/veg. If you aren't it is running a little too retarded which I believe leads to higher EGT's?

Are you sure your glowplugs are not getting some kind of voltage after the initial "glow"?

[Volvoist]

Hmm, I did have the timing to the Euro spec'd setting, somewhere around 0.93 I believe... that and the bio in the cold, that could have contributed. I'd just like to know for sure... I want to avoid this mishap again, if in fact it was my fault and was preventable...

[michaelovitch]

Like written the good glow plugs are BOSCH : 0 250 201 032 / 80010


If one broke off in the engine that's mean your injection system was not properly tuned : leaky injectors or bad advance or bad release pressure.
VO tends to make the nozzles very dirty and make the spray pattern bad the more you use it.

Like i wrote yet VO is a way thicker ,and so slower, when you inject it (even very well heated) that mean you need to retune according to it's own properties.

With normal fuel the correct advance on a d24 t is 0.87 to 0.95 when checking and works good at 0.95.

with VO it's very different.....

Try this yet :

http://www.forum4x4.org/threads/8941...A-GAZOIL/page5


VO needs to be heated and filtered VERY WELL !!

[Volvoist]

I have/had been running biodiesel, bought from a company locally that does biofuels. It is already filtered, washed, etc. Even some PennDot vehicles and equipment run fuel from this place. That said, what should I be running the timing at? I want to be able to switch back and forth. I had four break off, one was burned out (may have been as I noticed it stumbled a little at start up for a few weeks leading to this event), and the other was fine. I am sending the injectors to a close friend in NY with some parts that he ordered from me, and will have him test them, first with the biodiesel after chilling it in the refrigerator, then at ambient temperature, then with regular diesel. I want to know once and for all what in the hell happened to my motor so I can prevent this mishap in the future.