aaz injection timing for bio diesel

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moby
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aaz injection timing for bio diesel

Post by moby »

I just finished swapping an AAZ into my vanagon. It runs great! I ran my first tank of WVO biodiesel today and It runs fine untill the RPM's get high and then it acts like its running out of fuel.(jerky lack of power until I back down on the pedal and it runs fine again.) I have a 2 tank system and when this happens and I switch it to dino it immediately runs fine again. Both tanks use the same filter so I'm ruling that out. My timing is set for .034. Haven't pop tested my injectors, but I rebuilt them with new nozzles. The previous engine (Stock 1.6 diesel) ran fine with the same batch of bio. I'm wondering if the AAZ injection pump timing needs to be advanced a bit for Bio.? What do you guys think? Thanks, Paolo
moby
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Re: aaz injection timing for bio diesel

Post by moby »

Just did som research and I had it wrong about "advancing" the IP timing, I guess biodiesel burns quicker than dino and thus benifits from a more retarded timing. Would running biodiesel with an overly advanced timing create the symtoms I have? Thanks, Paolo
mtran
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Re: aaz injection timing for bio diesel

Post by mtran »

I dont use BD, but it way eazy to have separate filter,even inline for D is ok for me.
I use advance as better.
It look like you need more BD in uper RPM-restriction same place,mostly filter.
I`ll improve my English
Fatmobile
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Re: aaz injection timing for bio diesel

Post by Fatmobile »

Sounds more like fuel starvation.
A vacuum gauge on your fuel line will let you know if there is a restriction.
'91 Golf gasser converted to turbo diesel.
'83 Rabbit gasser, converted to diesel, then converted to run on vegetable oil.
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moby
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Re: aaz injection timing for bio diesel

Post by moby »

Vince, you nailed it! I installed clear lines and indeed I was getting a whole bunch of air at high rpm's. It was leaking in from a fuel fitting. Runs great now. Thanks for the help, Paolo.
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