[MHml] Seal swell on Diesel engine. (Not Multihull Content)

[RTHUTCH at caltex.com.au]

My advice now is that it is the Aromatics that affect seal swell - and the
additive that we add is not aimed at this problem. The additive is for
lubrication issues associated with Low Sulfur Diesels.

My Fuels people tell me that the main problem is with Hydrocracked Low
Sulfur Diesel fuels mainly manufactured in Asia and Japan and imported to
NZ and other areas but not so much to Aust (We Hydrotreat). The worst
affects from low Aromatics are when this percentage changes quickly from
say 30% to 15% and does not allow the seals to adapt to the lower Aromatic
fuel. There was quite a few problems with one particular older model of
Toyota Land Cruiser too but they tell me that older systems will have more
problems from low Aromatic Diesels. (If you only  fill up at irregular
intervals this could cause the big change in Aromatics or if you change
from one company with good Aromatics to an import with low Aromatics). We
target >15% and can experience problems below this target. Another oil
company in Oz did this late in 2004 or early last year and it cost them
Millions to repair all the problems!!

I have no idea what properties Vegetable Oil has. Sorry


Regards
Bob Hutchings
Area Specialist
Caltex Refinery, Kurnell
Tel: 9668 1305
Mobile: 0403 266 049