CAV Pumps and alternative fuels.

[Sleepy]

Currently exploring the alternative fuel options for my 2.25 Diesel.

It seems the CAV pump is the weak point. I am told the higher viscosity of SVO or WVO will kill the pump.

So what are my options:


Dilute the WVO/SVO with Diesel?
Modify the CAV pump (sounds expensive)
Run a dual system only switching when the fuel is hot enough to lower the viscosity. (sounds like a bit of frigging around)
Run on Biodiesel ( or a percentage of?)
Stick with fossil fuels.


Thanks Paul
<<BIO NEWBIE>>

[Blknight.aus]

put a fuel system heater in (search up on the thread I did on how I've setup fozzy) then run whatever the hell you like. once the bio eats away the rubber seals in your cav pump remove it and have new seals fitted.

to date Ive trialed

100% diesel
100% bio diesel
100% cooking oil
100% Wvo
100% cooking fat

the cooking fats the hardest to use requiring a long run to get it melty enough to be pumped and if used like wvo tends to suspend a lot of water.

[isuzurover]

Plenty of info around if you google, e.g:


I've read that some diesels and some injection pumps don't work well on SVO or WVO - is this true?

Lucas/CAV pumps are reportedly the most likely to fail on SVO. It seems they are subject to high wear rates and have some components that cannot withstand the higher viscosity of SVO (even heated, SVO is thicker than diesel fuel). However, many people use a cautious approach of very fine filtration and thorough heating, and have not experienced failures. The Lucas/CAV would almost certainly not survive long with a single tank system, where the engine is started on SVO . By contrast, the Bosch inline pump as found on older Mercedes engines seems to be especially tolerant of SVO.

PlantDrive™ - WVO, SVO vegetable oil fuel system, gas alternative, biodiesel (http://www.plantdrive.com/html/faq.html)



Some diesel pumps like LUCAS CAV DPA injector pumps are intollerant because the plungers can get gummed up really quickly
Land Rover Owner :: View topic - RUNNING ON PURE VEG OIL (http://www.lro.com/forum/viewtopic.php't=1567&start=20&sid=e7ba562ba5a40e69ffbb18388db61755)


I regularly run mine on (commercial) B20 with no issues. I think if you want to ensure a long pump life, the bio or a dual-tank system with a VERY good heat exchanger are the only options.

Also, it has recently been found that Bio (and possibly S/WVO) increases fuel dilution, so you need to increase oil change frequency.

[Sleepy]

Thanks Ben,

Yes I have done a bit of surfing on the subject and I guess I need to step back a level and understand the difference between Bio-diesel and S/WVO.

The idea of running on something other than dino-fuel appeals to the greenie in me, but there probably isn't an economic reason to do it as my S3 is not a daily driver.

Would it be complex to change the pump to something that could handle the higher viscosity?

Thanks for the links to.



Paul

[Blknight.aus]

yep, if you want a better pump you update the motor to a TDix00 and pull the turbo off. the TDi 200 is the best bet if you can get a good one.

[Sleepy]

ok.:eek:...............I think that answers my question;)

[Blknight.aus]

ok

basically

XX % bioD or xx/yy means its a blend of biodiesel and dino diesel

Bio/Biod/BioDiesel is a product created by the refinement of alternate base oils into a pure fuel that is very close in specification to Dino Diesel.

WVO is Waste Vegetable Oil, typically used cooking oils from places like chineese/fish and chip/hamburger shops.

SVO Is Straight Vegetable oil basically the same as above but before they cook with it, this is the best thing to use while you learn to make Biodiesel.

Cooking fat/Copher, its a denser version of cooking oils and doesnt flow till its heated or processed.

the biggest killer for the cav pump on the diesel is the viscosity and the water content, the filter will take care of all the chippy bits.

if youd like I can get round to photographing the end result on fozzy (well nearly the end result I have some bugs to work out for running WVO straight off of the bat but I get good results on any blend of bio Ive got the schematic for it posted up here somewhere

http://www.aulro.com/afvb/803855-post15.html

there

[Sleepy]

Dave,

I am very interested in what you've done with Fozzy however didn't want to impose. I have surfed around alot and including the Aulro, Bio Forum in Sydney and others in the UK. I have also seen a couple of books on Amazon that look like a good read too. Nothing like first hand knowledge though:)

I must admit when I bought the 2.25D I had thought "great I can run it on chip fat" thinking that it was a simple old thing. Alas it wasn't quite as I assumed - I think it was Ben who first raised my awareness of the issues with the CAV. :(

The motor has just been rebuilt last year:) - I have receipts for many thousands for injectors and pump rebuilds - that's what attracted me to the vehicle. The last thing I want to do is stuff up a nicely rebuilt motor.

So, in short, I aim to learn a lot more on how to run and maintain my 2.25D but I am starting from a low knowledge level ;)

[Blknight.aus]

everyone starts some where and with AULRO's compendium of brainage at your fingertips if youve got the willingness to ask questions your starting point is a lot better off than a lot of other peoples....

Since Im having a heap of people over this saturday Im sure someones going to spot the huge tank in the back of the car and ask...

I'll get photos taken of the setup and do a talk though of it although Ive hit a few hiccups of late due to cooling weather and a few other things.


Fortunately for me I have a line on 3 backup injector pumps that are workable enough to get an engine to running.

getting the 2.25 to run on cooking oil (not fat) is easy if you live in townsville paint a drum black leave it on a black concrete pad in the sun with a small solar powered fan to suck the evaporating water out of the drum, filter it and your pretty much good to go, the engine now in fozzy ran on that as a trial to make sure it would work back when I was just thinking about playing with WVO.

[curnowdj]

G'Day Gang,
just came across this old thread. I can tell you the cav pump weak point is the vanes in the distributer head of the injection pump. The extra viscosity of the wvo breaks the vanes off. Had this happen on a cav in a nissan urvan. The VE pumps are almost bulletproof.
Cheers