killed ANOTHER pump with too much fuel pressure
05-08-2007, 12:36 AM
#31
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What would cause the leaking? Is the ULSD less viscous than the old stuff?
05-08-2007, 01:37 AM
#32
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Wcbcruzer,
The leaking seals are directly related to the new ULSD and how it's made. By using extreme heat to remove the sulfur in LSD to get it to ULSD specs, the refineries are also removing (not purposely, but as a by-product) most of the petroleum aromatics in it as well. The problem arises because the aromatics like certain petroleum products will cause certain types of seals to "swell" a bit. That is normal. When these aromatics are taken out of the LSD with the high temperatures, the ability of the cleaner ULSD to keep seals "swollen" is greatly reduced. So, seals that have run immersed in LSD for many miles and have swollen to a certain point, will tend to shrink when the newer, cleaner, aromatic-free ULSD is used on a regular basis. It happens slowly over time but it WILL happen. The problem was considered a serious one and several internal memos by Chevron engineers pointed to very little to no way of correcting the problem. Their only solution was to alert OEM's of the problem and to have them suggest to vehicle owners with potentially leak-prone equipment to have their seals retrofitted to meet the requirements of the new ULSD fuel. It's a problem that is going to escalate. Seals that may have spent years running in LSD will take longer to shrink/leak than those that are newer and haven't run all that long. The good thing is that vehicles with low mileage and less run time on the older LSD shouldn't show much if any affect from running ULSD. Hope this helps.
The leaking seals are directly related to the new ULSD and how it's made. By using extreme heat to remove the sulfur in LSD to get it to ULSD specs, the refineries are also removing (not purposely, but as a by-product) most of the petroleum aromatics in it as well. The problem arises because the aromatics like certain petroleum products will cause certain types of seals to "swell" a bit. That is normal. When these aromatics are taken out of the LSD with the high temperatures, the ability of the cleaner ULSD to keep seals "swollen" is greatly reduced. So, seals that have run immersed in LSD for many miles and have swollen to a certain point, will tend to shrink when the newer, cleaner, aromatic-free ULSD is used on a regular basis. It happens slowly over time but it WILL happen. The problem was considered a serious one and several internal memos by Chevron engineers pointed to very little to no way of correcting the problem. Their only solution was to alert OEM's of the problem and to have them suggest to vehicle owners with potentially leak-prone equipment to have their seals retrofitted to meet the requirements of the new ULSD fuel. It's a problem that is going to escalate. Seals that may have spent years running in LSD will take longer to shrink/leak than those that are newer and haven't run all that long. The good thing is that vehicles with low mileage and less run time on the older LSD shouldn't show much if any affect from running ULSD. Hope this helps.
05-08-2007, 09:41 AM
#33
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Wcbcruzer,
The leaking seals are directly related to the new ULSD and how it's made. By using extreme heat to remove the sulfur in LSD to get it to ULSD specs, the refineries are also removing (not purposely, but as a by-product) most of the petroleum aromatics in it as well. The problem arises because the aromatics like certain petroleum products will cause certain types of seals to "swell" a bit. That is normal. When these aromatics are taken out of the LSD with the high temperatures, the ability of the cleaner ULSD to keep seals "swollen" is greatly reduced. So, seals that have run immersed in LSD for many miles and have swollen to a certain point, will tend to shrink when the newer, cleaner, aromatic-free ULSD is used on a regular basis. It happens slowly over time but it WILL happen. The problem was considered a serious one and several internal memos by Chevron engineers pointed to very little to no way of correcting the problem. Their only solution was to alert OEM's of the problem and to have them suggest to vehicle owners with potentially leak-prone equipment to have their seals retrofitted to meet the requirements of the new ULSD fuel. It's a problem that is going to escalate. Seals that may have spent years running in LSD will take longer to shrink/leak than those that are newer and haven't run all that long. The good thing is that vehicles with low mileage and less run time on the older LSD shouldn't show much if any affect from running ULSD. Hope this helps.
The leaking seals are directly related to the new ULSD and how it's made. By using extreme heat to remove the sulfur in LSD to get it to ULSD specs, the refineries are also removing (not purposely, but as a by-product) most of the petroleum aromatics in it as well. The problem arises because the aromatics like certain petroleum products will cause certain types of seals to "swell" a bit. That is normal. When these aromatics are taken out of the LSD with the high temperatures, the ability of the cleaner ULSD to keep seals "swollen" is greatly reduced. So, seals that have run immersed in LSD for many miles and have swollen to a certain point, will tend to shrink when the newer, cleaner, aromatic-free ULSD is used on a regular basis. It happens slowly over time but it WILL happen. The problem was considered a serious one and several internal memos by Chevron engineers pointed to very little to no way of correcting the problem. Their only solution was to alert OEM's of the problem and to have them suggest to vehicle owners with potentially leak-prone equipment to have their seals retrofitted to meet the requirements of the new ULSD fuel. It's a problem that is going to escalate. Seals that may have spent years running in LSD will take longer to shrink/leak than those that are newer and haven't run all that long. The good thing is that vehicles with low mileage and less run time on the older LSD shouldn't show much if any affect from running ULSD. Hope this helps.
ummm, what he said.....minus the chevron memo stuff.
05-08-2007, 08:44 PM
#35
Chapter President
Just stick around and you'll be as smart as the rest of us.
While i was working on some pumps at a local Terminal is asked about the lubricity of the ULSD. They told me that they put lube in the fuel as it is pumped into the tankers. Didn't tell me what it was tough. I still run PS in everytank.
While i was working on some pumps at a local Terminal is asked about the lubricity of the ULSD. They told me that they put lube in the fuel as it is pumped into the tankers. Didn't tell me what it was tough. I still run PS in everytank.
05-08-2007, 09:00 PM
#36
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05-08-2007, 09:15 PM
#37
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