Ulsd Question

[rdodd]

I understand that fuel additives like stanadyne and power service will help with lubing the pump on our first gen trucks but is there an additive that will replace the lost aromatic content of the new ulsd to keep our ve pump seals from shrinking and leaking?

 

[dpuckett]

Not that I know of. Apparently, the aromatics were part of the pollution problem. Or was it just that they were removed along with the sulfur?



Daniel

 

[DVolk]

add 2 stroke oil to the tank



2 stroke oil produces a ash there fore it will put it back into the deisel ,

theres anouther thread were a guy is useing it and 10weight oil and that standyene /powersorce with good results

 

[RWWinslow]

Chevron provides the following information on fuel system seals and ULSD:



Will low sulfur diesel or low aromatics diesel cause fuel system leaks?

The introduction of low sulfur diesel for on-road use in the U. S. was accompanied by fuel system leaks in a very small percentage of vehicles. Investigations into the cause of these leaks suggest that the problem was linked to the change in the aromatics content of the fuel and to seal material and age.

Diesel fuel systems contain "O-rings" and other parts made of elastomeric materials. These elastomers swell slightly when they contact diesel fuel, because they absorb aromatic compounds from the fuel. Exposure to a fuel with a lower aromatics content will result in some of the absorbed aromatics being leached out, causing the elastomer to shrink towards its original size. If the elastomer is still pliable, this shrinkage will not cause a leak. However, if age or service at higher-than-normal temperatures has caused the elastomer to loose its elasticity, a leak could occur. Vehicle owners should be aware that elastomeric parts have finite lives and should be replaced as necessary.



By itself, low sulfur or low aromatics diesel fuel does not cause fuel system leaks. They are caused by the combination of a change from higher to lower aromatics fuel and aged O-rings and elastomeric parts that have lost their elasticity.

My work, Idaho National Lab, is doing a complete technical review on ULSD - one of the areas of review is the effect of ULSD on older diesel engines.



ULSD has adequate lubricity additives put into the fuel at the terminal. There have been some negative interactions between some of these lubricity additives and motor oils in the past - two cycle oil / ATF, etc. may or may not fit into this category - I would not chance it. The VE rotary style pump lubrication is dependent upon a surface interactive chemistry lubricant which is how the lubricity additives perform. Two cycle oil / ATF / engine oil does not have this same type of chemistry.



PM me or contact me via phone if you have more questions on this subject. Once the technical review / paper is complete we will look at posting it on our web site and or getting it to the TDR.