Vegetable Oil SVO WVO waste cooking oil as biofuel

[100k]

First off just like to say hello. I just found this forum, but have been doing veg for quite a while now (almost 6 years) I have a 85 jetta with about 150k veg miles and a 96 cummin with about 15k on it, both of which were driven to AK from MN on veg!

please, insults don't help me so if i've done something blaitantly wrong, there's a proper way to tell me besides you f-ing idiot style.

My system is a 2 tank system, hih basically exactly the same as Sunwizards. My oil is between 160 and 180 before injection, I live in MN so i have a fair sized heating coil in the tank or else it just doesn't melt enough to run when temps are really cold. I noticed basically right away that when on veggie oil on accelerating hard that the truck wouldn't really start to pull hard until 250 rpms or so later than when on diesel, and now seems to be a little worse, maybe approaching 400. diesel starts to pull good and hard at about 1500 to 1650. I have 3/8" fuel line with a pressure gauge inbetween IP and filter stays in the 10 to 20 psi range when at these rpms, low end being under heavy acceleration of course. I really don't think it's flow restriction. What I'm leaning towards is injector coking.


Reading on here I realize that I have to do more checking my moisture content as well as FFA. Could either of these be linked to my performance issue? I have also noticed that my idle is also slower than on diesel by about 100, I saw another post on that same thing, but, it didn't follow up with the solution...

I've been running the same veggie filter on my Volkswagen for about 70k now, just to see how well i've been filtering, I don't think that is the issue. The trucks has been changed every 5k just because.

Well, any suggestions/advice, very welcome. I'm not online a whole lot but I'll get back to comment once a week or so. Thanks in advance!

[SunWizard]

My 95 has the same power at the same RPMs on WVO and diesel. How many miles on your truck? It could be the injectors, from your description I can't think of anything else. Water in your WVO could have eroded the injectors over time. Its an easy and cheap fix to try swapping them.

[100k]

Truck only has 172k on it. You say an easy and cheap fix....would you suggest the 300 hp injectors or stock? Ebay? Can I see the erosion if they are worn?

[SunWizard]

Truck only has 172k on it. You say an easy and cheap fix....would you suggest the 300 hp injectors or stock?

Stock. Anything higher can lead to smoking which is bad when burning WVO, mostly since partly burned WVO can get in your motor oil and thicken it.

Ebay?

That's where I got mine, but I haven't needed to install them yet at 195k.

Can I see the erosion if they are worn?

Depends on how bad they are. Best to take them to a shop who works on them and they could check them out and give you an opinion. They might sell you a set for something close to ebay prices.

[100k]

Thanks SunWizard, I'll be looking into things and let you know what I find.

I had talked with you on the phone a couple of years ago when I was converting my dodge and had asked you a few Q's about how many miles and what not you have on veg....BTW, what are you up to now?

[100k]

well I pulled the injectors and they really don't look bad....a little coking on the tips but not bad. I figured I'd clean them up and see how it feels, i got nothing to lose but my time.

The coking was about 1mm worth of carbon so that could affect the spray pattern. I will post a pic of the injector tip later.

Sunwizard, how many wvo miles do you have on your dodge now? still no problems ever?

[SunWizard]

Sunwizard, how many wvo miles do you have on your dodge now? still no problems ever?

60k, no problems. What is inside the injectors where you can't see matters more than the outside.

[beeline]

I noticed about the same 100rpm idle drop and no real power when under 1600rpm. With 10 - 15% diesel or jet fuel it becomes almost unnoticeable what fuel is used. so, maybe add some of the above and see what effect it has.

[wydra]

10 - 20 psi for fuel pressure would be low. I notice a difference as soon as mine gets down to 25 under WOT. I personally like a higher fuel pressure. 30 psi or more.

[777funk]

Different vehicle so the actual numbers won't apply. But with my Powerstroke (electric fuel supply pump), I have the diesel at 60 psi approx and the veg I have an adjustable regulator. If I set it at 40 or below I notice a lack of power when I switch to the veg system. If I set the veg pressure to 50-60, it's exactly the same power as diesel (same speed and power when switch is flipped).

So having plenty of fuel pressure helps. Lack of fuel pressure = bogged down.