tditom
Top Post Dawg
- Joined
- Sep 5, 2001
- Location
- Jackson, MI
- TDI
- formerly: 2001 Golf GL, '97 Passat (RIP) '98 NB, '05 B5 sedan
interesting document someone shared on bimmerfest:
http://www.acea.be/images/uploads/aq/Final%20WWFC%204%20Sep%202006.pdf
(my comments are in [])
US fuel is not required to protect your pump
use an additive of your choice for lubricity
http://www.acea.be/images/uploads/aq/Final%20WWFC%204%20Sep%202006.pdf
(my comments are in [])
take a gander at Figure 16 on the bottom of page 49.page 49 said:
LUBRICITY
The lubricating components of the diesel fuel are believed to be the heavier hydrocarbons and polar fuel
compounds. Diesel fuel pumps, without an external lubrication system, rely on the lubricating properties
of diesel fuel to ensure proper operation.
Refining processes to remove sulphur tend to simultaneously reduce diesel fuel components that provide
natural lubricity. As diesel fuel sulphur levels decrease, the risk of inadequate lubricity also increases;
however, poor lubricity has been observed even in diesel fuels with very high sulphur levels. Inexpensive
additives can be used instead of changing the refining process to achieve the desired lubricity level.
Influence of Lubricity on Pump Wear
Inadequate lubricity can result in increased tailpipe emissions, excessive pump wear and, in some cases,
catastrophic failure. Concerns over problems experienced with fuels with poor lubricity led to a significant
international collaboration between oil companies, OEMs, additive companies and pump manufacturers to
develop a test method and performance limit for fuel lubricity. The resultant method, the High Frequency
Reciprocating Rig (HFRR) procedure, is a bench test that provides good correlation to measured pump effects.
Figure 16 shows the correlation between actual pump wear (measured by Bosch) and HFRR measured
wear scar diameter. Bosch's rating scale describes ‘normal wear‘ as less than 3.5 (which corresponds to a
nominal HFRR Wear Scar Diameter of 400 micron[corrected]). With a Bosch wear rating of 4 [425 micron?], the pump will have
decreased endurance, and ratings above 7 [540 micron?] indicate potential fatal breakdown.
US fuel is not required to protect your pump
use an additive of your choice for lubricity