Injection pump failures on veggie?

For discussing the modifications needed for diesel vehicles to run with 2 tank veggie oil conversions.

Moderators: SunWizard, coachgeo

Injection pump failures on veggie?

Postby jedidiahwiebe » Mon Aug 29, 2016 1:58 pm

Hey all! Long time lurker first time poster. My greaseride is a 1991 Delica l300. Been running excellent on VWO for 50 thousand km so far. Always use the cleanest oil, and filter to 1 micron. Suddenly overnight I developed a lack of power. Still idles fine, just won't rev out (on veg or diesel). When i start it up it revs out to about 2k, but then drops to 1k. Not much smoke or anything, no other notable symptoms. Turbo still spins fine, good fuel supply to IP, brand new fuel filter, Have cleaned filter screen at the outflow of the IP at junction with return line -does not seem to be one at the inflow. Pump does not leak, have verified that the shutoff solenoid is working, have checked that the boost pin or governor pin is not stuck, and have run ATF through the pump.

Has anybody else had this kind of problem?

I'm posting here, because i'm wondering if others using WVO are having injector pump problems? By the way it's been running great. Not slowly wearing out. I have not been adjusting the idle to compensate for a wearing out pump. Any suggestions as to what could be going on?

I will be checking the exhaust for blockage, running some weird injector cleaner gunk through it, and blowing compressed air backwards through the pump.

Looking for any more ideas before I have to pull the pump off (which means timing belt on the delica)

BTW the throttle linkage is good as well... seems to have some effect as it won't run well without pedal to the floor.

Could something in the governor linkage be gummed? Or is a spring broken? Or is there a tiny passageway like the one inside the fuel return line banjo bolt that is blocked? That's what it feels like. Like fuel is restriced somewhere. Only fuel flow is verified good up until the pump.

Thanks guys! Hope this discussion contributes well to community knowledge!
Posts: 3
Joined: Mon Aug 29, 2016 1:28 pm

Re: Injection pump failures on veggie?

Postby jedidiahwiebe » Mon Aug 29, 2016 4:06 pm

The exaust was not the issue. Currently running injector/ fuel system cleaner through with both intake and fuel return line in a 1l bottle.... Mixed at 60 times the recommended ratio. It'll do 2500 rpm now. So that's an improvement! Just reaffirms to me that something's gunked up. and needs un-gunking
Posts: 3
Joined: Mon Aug 29, 2016 1:28 pm

Re: Injection pump failures on veggie?

Postby jedidiahwiebe » Fri Sep 02, 2016 10:59 pm

Here's a link to a picture of the inside of my IP:

Replaced the IP, and it runs good. There was a ton of crud in there. Coating everything. I ran a concentrated dose of injector cleaner/ clearance priced snake oil through it for a while so that might have contributed to the fact that it was all soft and peeled off at the lightest touch as you can see in the picture.

WHAT AM i DOING WRONG here with my veggie system that i am getting this build up? I need to correct the problem before i eat another injector pump. As a sidenote, I have had the cyl head off a few times and there is minimal sign of coking or carbon buildup in there, nothing at all beyond what you'd see on a regular fuel engine of it's age.

I have a hotfox fuel preheated pickup in the tank, insulated lines, heated vegtherm filter mount, and one of those 12v inline electric thermostatically controlled heaters right before the IP. Am I not purging long enough?

I haven't been de-watering my fuel beyond simply letting water settle out, quite thoroughly and heating the oil during filter so that it can settle out. I have, however only been taking clear, non cloudy... clean veggie oil ALL this time. That's been my main de-watering method... just not using water contaminated oil.

Can anyone think of what might have caused this build up?
Posts: 3
Joined: Mon Aug 29, 2016 1:28 pm

Re: Injection pump failures on veggie?

Postby SunWizard » Mon Sep 05, 2016 12:05 pm

Thats polymerization, see this thread:
Yes your purge may be too short, and your dewatering may not be not enough. Do you hot pan test every batch for water? Water contributes to poly and can reduce the IP and injector life drastically. A big factor is how abused the WVO is, which I measure with simple FFA test strips, see WVO science project, FFA, standards and water testing:
YVORMV - Your veg. oil results may vary.
95 Dodge Cummins 4x4 SVO WVO conversion.
81 Mercedes 300D- stock and happy on V80/D20 blend.
Low fossil net zero house- 100% solar power and heat.
Site Admin
Posts: 1724
Joined: Mon Dec 11, 2006 2:53 pm
Location: N. Colorado

Return to 2 Tank veggie oil conversion and General discussion

Who is online

Users browsing this forum: No registered users and 0 guests