Okay, here it goes. I converted my 93 to run on WVO and when it's running on diesel it idles fine but when it runs on WVO the RPM's at idle drop so much I think it's gonna stall. I checked for air leaks and found my "new" pump was defective and replaced it with another one which seems to have remedied the air contamination but the idle is still really low. Could I have a worn out injector pump or something and it's not able to pump oil at low rpm's or something? I am having no loss of power or economy while running on WVO. I simply can't stop at a light without having on foot on the brake and one on the accelerator for fear of it stalling. Any ideas? Even the preposterous is welcomed!

 

Does it have decent power? Filters plugged up?
Are you filtering this WVO? Are you processing it, transesterfication?
Or, just poring into the tank and heating it?

 

I have the build fully documented in the alternative fuels section. Filter was changed with no improvement. Yes my oil is dewatered and filtered down to 5 microns. This is a dual tank heated system with no transesterification. Seems to be getting worse over time or maybe I'm just noticing it more. Like I said I have zero loss of power and I'm getting 17.2 MPG in a slightly modified 93 club cab 4X4 on WVO which I'm VERY happy with. Just won't idle right and the only thing I can think of is if my IP just won't handle the viscoscity of the oil??? Aliens from another planet f@#$ing with me?

 

How hot is your VO getting?

When VE pumps get worn out, the first symptom is low idle when hot. The heated VO may be showing up this problem, and the diesel cools the pump and makes it idle normally.

If you want to engineer around the problem, go to the junkyard and get an idle solenoid off a '70's or '80's car or truck. They used them to prevent dieseling on some cars and to keep other cars from dying with the A/C on. Mount it to hold the throttle lever above normal idle and run the power off the veggie switch.

 

I'ts probably hitting the injection pump about 150 or so maybe more when the truck is under load.

This is wierd. Today I ran it WOT going up a steep grade to make sure my new WVO lift pump will supply adequate fuel and when I stopped to check fittings and everything for leaks and air contamination (idling on WVO) It idled normally again! So now I don't know what the heck is going on. I'll have to keep an eye on it

Good idea! If my injection pump IS going bad which pump should I replace it with for WVO use?

 

Mine idles low on Jet A also. It's lighter fuel and I think the IP has trouble supplying enough pressure at idle. The "anti-diesel" solenoid from a lete 60's through about 80 car is a good fix. Another option for non WVO fuel is a cool can, but that requires regular ice replenishment!
It's depressing to think about replacing the IP though. Mine is only 5 or so years old....

 

I just ran to cali and back, 1500 mile round trip. Did a blend of 50% #2 and 50% veg with a shot of power service in it, thats unheated. Truck loved it. I would suggest trying some diffrent blends. Your saying on #2 it idles fine, but on heated veg it idles low and that "probably" its hitting the IP at 150. That temp sounds a lil low. Try about 30% #2/70% veg and a shot of ctane boost and see how it does.

Put a fram G2 filter between the LP and the primary filter to see if your airating the fuel. Doing this saves on having to change on the more costly truck fliter and allows you to see whats going on with your fuel( and can be changed in 5 min).

I lost a LP part way down and found a great lil pump that saved the trip. I'll do a short writeup with part # and pics tomorrow, I just got home and I'm burnt arter driving straight thru.

Stu

 

I don't want to blend. Trying to keep my operating costs down, that's why I have a 2 tank system. I always run Power Service or Howes in everything including my WVO. I already have a Fram G2 before the lift pump and also a poly air bleed line right before the 3 way valve that switches between WVO and diesel that ties into the return line and have not had any air contamination.

One thing I've noticed since the new lift pump is the low idle is intermittent now. sometime it idles fine. sometimes it idles low and yesterday once it was surging at idle!

 

i'm running 25 gal. wvo and 5 gal. diesel in a truck with 525,000 on it. stock lift pump.stock IP.it is 75 degrees in the day and 55 at night around here right now(south eastern pa.).when i start it in the morning the engine has low idle and then surges once,like the governor is stiff.that's in a matter of a few seconds.then it streightens out and runs normal.in the afternoon at work it starts like it has streight diesel in it.when the weather gets colder i use more diesel until it gets to about 45 degrees then i switch to diesel.

 

Sounds like you got it dialed in! I know there's gotta be alot of people running straight WVO with stock pumps with no problems but I'm just trying to figure out if maybe I modified my IP too much for wvo or maybe not enough etc. or maybe that's not it at all and I'm barking up the wrong tree.

 

the truck with 525 thousand has had nothing done to the pump ever.factory settings.i have another truck with about 135 thousand on it.the fuel screw is turned in as far as i can without runaway.star wheel is down and stock fuel pin. they both act the same on wvo.