JB & bio diesel and common rail

[Guest]

JB,
As Julian says, keep to the stuff that has been made into an ester. I
have worked on the technical side of this production with some very
technical German consultants (Gopa consult) trying to solve some post
Chernobyl problems. The neat veg oil mixed with diesel can cause
gumming and all sorts of problems with valve stems and piston rings
etc. Short term seems OK, long term is bad.
Common rail.
No we don't have it in the 80. But its now the common standard for
new diesels. On your 80 the injector pump squeezes fuel down the line
in separate pulses to each of the 6 injectors on the engine, which is
all timed and powered from the crankshaft. With common rail, one pump
provides a continuous high pressure fuel line to a manifold along the
side of the head - the 'common rail'. So with a constant high
pressure of fuel right in the cylinder head, the injectors are in
fact electric valves that let the high pressure fuel through to the
cylinders in sequence. So the fuel system relies on a very reliable
electric/electronic engine management system. Ask the owner of a new
Hyundai Galloper what they think about them ! Thankfully the Toyota
system in the newer models works well. But the BMW TD5 in the LR
models is not so successful. So much so that the British army only
has the old 300TDi engine fitted with 'normal' injection in new vehicles.
HTH
Cheers
Jon
Grand Union Canal
'92 HZJ80 ex UN surplus from Bosnia.

 

[Guest]

Hi Jon C-W
Thanks for that explanation of the common rail.
I have been asking some questions on this other site and even though I am
mechaniclly challanged some of the answers I got back seemed just not to fit
in me little mechical brain. I got the impression that it would be alright
to buy veg oil from the supermarket and pour it in the tank at 50% ratio and
all would be fine.
I looked at the site Clive sent me and the mix of chemicals needed with the
veg oil and decided to leave well enough alone.
A conversion to run the 100% stuff costs here about 1200 euro and it would
take me a while at savings of 30 cent per litre to recover the cost.
There was also the case of a fleet of Transit vans that stopped in the one
week after a while running on the 100% stuff.
When the engines were stripped they found a residue like what you would find
on the sides of your chip pan on the head.
So it would appear that not all of the veg oil burned cleanly enough with in
the engine.
I know it may seem like basics to a lot of you guys but to me who has never
seen the inside of an engine its like taking a flight to mars , well maybe.
Sorry but heres a few of the usual stupid questions Sorry.
What is the head and what is in it,
I know fuel is pumped into the engine to push the pistons down by an
explosive action which in sequence will drive the crankshaft but where else
will fuel go or end up in the combustion process.
It just to me Diesel is a lot tinner in voscosity that veg oil and I just
dont see how an engine made to use one can run on the another with out any
issues over time. I know im sad but thats me.
How come Diesels cant use petrol or the petrol ones cant use Diesel or is
that a whole book to read with a bottle of plonk.
cheers
John C
92HDJ 80 1HDT Rep of Ireland