[Vwdiesel] biodiesel requiring a rebuilt injection pump on an '84 Rabbit

[Bryan K. Walton]

Hi everybody,

I have a question for the list concerning the effects of biodiesel (in
high % blends) on the injection pumps of A1s (my case -- 1984 Rabbit).

I purchased this rabbit in December of 2005. It has approximately
121,000 miles on it. I've been running B20 in it so far. A few months
ago, I had a mechanic upgrade the fuel lines to viton lines in
preparation for me raising my concentration of biodiesel. I've
purchased a new fuel filter and have planned to up my percentage of
biodiesel to B60 sometime in April (and then go to B100 in June).
Today, I read something on the Frybrid mailing list that made me halt
my plans. Here is the link, to that thread:
http://www.frybrid.com/forum/showthread.php?t=3571 In this thread,
Chris Goodwin, owner of Frybrid, states that when running biodiesel,
"early VW products will need a rebuilt Injection pump or they will
leak at the advance plate, then at the face seal, the biodiesel will
turn the cam belt to mush and the engine will bend valves and need 
rebuilding."

I can handle a leaking fuel line, but rebuilding an injection pump is 
frightening! And I don't even want to think about having to rebuild my
engine. What is the story here? 

Would Chris's scenario happen slowly enough that I could fix the
injection pump before there was engine damage? Or are we talking about
something that would happen almost immediately?  What symptoms would I
see if Chris's scenario started happening to my IP?  Is there anyway I
can determine what the seals are made of on my IP, short of waiting for
disaster to strike?
 
Any VW owners out there (with circa 1984 diesels) running biodiesel
in high blends that can speak to this and their personal experiences?

Thanks in advance,
Bryan