I repeat: What were the wear values for iron, crome, aluminum, which is the important information. ED
DI fuel injectors and fuel dilution
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Real question for those in the know:
How much will 5% fuel dilution decrease the viscosity of an engine oil.
5% of 1 gallon (128 ounces) is only 6.4 ounces of fuel.
How much of a decrease in viscosity are you going to have with a 40 weight oil, a 30 weight oil, or a 20 weight oil?
Thanks,
BC.
How much will 5% fuel dilution decrease the viscosity of an engine oil.
5% of 1 gallon (128 ounces) is only 6.4 ounces of fuel.
How much of a decrease in viscosity are you going to have with a 40 weight oil, a 30 weight oil, or a 20 weight oil?
Thanks,
BC.
Originally Posted By: Bladecutter
Real question for those in the know:
How much will 5% fuel dilution decrease the viscosity of an engine oil.
5% of 1 gallon (128 ounces) is only 6.4 ounces of fuel.
How much of a decrease in viscosity are you going to have with a 40 weight oil, a 30 weight oil, or a 20 weight oil?
Thanks,
BC.
The viscosity of a mixture is heavily skewed towards that of the lower viscosity component, but, IIRC, there isn't any established way to calculate how much. I did have a look for one a long time ago, but no dice.
I posted about it somewhere and MIGHT be able to find the post if its important.
Real question for those in the know:
How much will 5% fuel dilution decrease the viscosity of an engine oil.
5% of 1 gallon (128 ounces) is only 6.4 ounces of fuel.
How much of a decrease in viscosity are you going to have with a 40 weight oil, a 30 weight oil, or a 20 weight oil?
Thanks,
BC.
The viscosity of a mixture is heavily skewed towards that of the lower viscosity component, but, IIRC, there isn't any established way to calculate how much. I did have a look for one a long time ago, but no dice.
I posted about it somewhere and MIGHT be able to find the post if its important.
But meanwhile, back in The Lab:-
http://www.spectrosci.com/product/q6000/?fileID=8a8081894ccb3b72014d104badbb2999
"Viscosity measurement is effective when fuel dilution ranges are
above 5%. The SAE viscosity range is broad enough that fuel dilution
up to 5% can be tolerated. Synthetic motor oils maintain their grade
better than mineral oils."
OTOH, from the same people
"Fuel dilution in oil can cause serious engine damage. High levels of fuel (>2%) in a
lubricant can result in decreased viscosity, oil degradation, loss of dispersancy, and
loss of oxidation stability. Fuel dilution is one of the most important lubricant failure
modes in internal combustion engines."
http://www.spectrosci.com/product/q6000/?fileID=8a8081894ccb3b72014d104badbb2999
"Viscosity measurement is effective when fuel dilution ranges are
above 5%. The SAE viscosity range is broad enough that fuel dilution
up to 5% can be tolerated. Synthetic motor oils maintain their grade
better than mineral oils."
OTOH, from the same people
"Fuel dilution in oil can cause serious engine damage. High levels of fuel (>2%) in a
lubricant can result in decreased viscosity, oil degradation, loss of dispersancy, and
loss of oxidation stability. Fuel dilution is one of the most important lubricant failure
modes in internal combustion engines."
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Calculation of the viscosity of a mixture.
http://profmaster.blogspot.tw/2007/12/how-to-calculate-viscosity-of-liquid.html
(a) Its complicated
(b) It apparently doesn't work with viscosity index improvers, so not much use with most oils.
I'd guess there might be some experimental lookup tables out there somewhere, but they might only apply to the specific formulations used.
http://profmaster.blogspot.tw/2007/12/how-to-calculate-viscosity-of-liquid.html
(a) Its complicated
(b) It apparently doesn't work with viscosity index improvers, so not much use with most oils.
I'd guess there might be some experimental lookup tables out there somewhere, but they might only apply to the specific formulations used.
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Fuel dilution is often squealed about here but seems to cause no issues at all. I cannot recall a single FD issue that caused any damage to an engine.
These high power density 4 bangers are already stressed and adding DI and the necessary tuning is obviously a bit much for the oil, especially 20w.
These high power density 4 bangers are already stressed and adding DI and the necessary tuning is obviously a bit much for the oil, especially 20w.
Originally Posted By: SteveSRT8
Fuel dilution is often squealed about here but seems to cause no issues at all. I cannot recall a single FD issue that caused any damage to an engine.
These high power density 4 bangers are already stressed and adding DI and the necessary tuning is obviously a bit much for the oil, especially 20w.
In modest doses, fuel dilution does seem rather harmless and is probably unavoidable in DI engines. But when it exceeds 5% after a long highway run, it's hard to believe something isn't wrong that will compromise the long-term durability of the engine, good UOA wear metals notwithstanding.
This level of dilution reduces my Mobil1 0w-20's viscosity from 8.7 to around 7.0 in the first 1,000 miles. While still in-grade I wonder what it would look like after the 10-11,000 mile OCI Honda's IOLM suggests. So I agree the spec'd 20w is under considerable stress and suspect 0w-30 would be a safer choice.
Fuel dilution is often squealed about here but seems to cause no issues at all. I cannot recall a single FD issue that caused any damage to an engine.
These high power density 4 bangers are already stressed and adding DI and the necessary tuning is obviously a bit much for the oil, especially 20w.
In modest doses, fuel dilution does seem rather harmless and is probably unavoidable in DI engines. But when it exceeds 5% after a long highway run, it's hard to believe something isn't wrong that will compromise the long-term durability of the engine, good UOA wear metals notwithstanding.
This level of dilution reduces my Mobil1 0w-20's viscosity from 8.7 to around 7.0 in the first 1,000 miles. While still in-grade I wonder what it would look like after the 10-11,000 mile OCI Honda's IOLM suggests. So I agree the spec'd 20w is under considerable stress and suspect 0w-30 would be a safer choice.
If I understand everything correctly from this thread there are multiple samples with the same level of fuel dilution. It is being considered a "problem" because it is a higher level than traditionally seen. Honda can find nothing wrong with the engine.
First, a blanket statement that x% of fuel dilution will cause issues is flat out wrong. The engine system is designed to operate with a certain level of oil film thickness. Do we really think that Honda engineers haven't encountered similar fuel dilution issues and therefore designed around the know fuel dilution? Unfortunately, only the engineers that developed the engine would have the answer but I think we can see from the wear values that everything is fine.
When fuel dilution becomes an issue the wear values start to skyrocket and there is no mistake that a problem is present. Just because fuel is present does not mean there is a problem if the engine was designed for it.
OP, drive on with confidence.
First, a blanket statement that x% of fuel dilution will cause issues is flat out wrong. The engine system is designed to operate with a certain level of oil film thickness. Do we really think that Honda engineers haven't encountered similar fuel dilution issues and therefore designed around the know fuel dilution? Unfortunately, only the engineers that developed the engine would have the answer but I think we can see from the wear values that everything is fine.
When fuel dilution becomes an issue the wear values start to skyrocket and there is no mistake that a problem is present. Just because fuel is present does not mean there is a problem if the engine was designed for it.
OP, drive on with confidence.
Originally Posted By: 09_GXP
If I understand everything correctly from this thread there are multiple samples with the same level of fuel dilution. It is being considered a "problem" because it is a higher level than traditionally seen. Honda can find nothing wrong with the engine.
First, a blanket statement that x% of fuel dilution will cause issues is flat out wrong. The engine system is designed to operate with a certain level of oil film thickness. Do we really think that Honda engineers haven't encountered similar fuel dilution issues and therefore designed around the know fuel dilution? Unfortunately, only the engineers that developed the engine would have the answer but I think we can see from the wear values that everything is fine.
When fuel dilution becomes an issue the wear values start to skyrocket and there is no mistake that a problem is present. Just because fuel is present does not mean there is a problem if the engine was designed for it.
OP, drive on with confidence.
You may be exactly right; this issue could be my personal "white whale", I might be a happier camper had I never heard of "used oil analysis" or "fuel dilution" and at the end of the day it may mean nothing.
On the other hand:
1) The level of fuel dilution in my example is substantially higher than any other UOA I've seen from a Honda K24W engine
2) Honda USA claims to have never seen another fuel dilution complaint for this engine
3) While Honda can't find anything wrong, they are also not able to tell me that this level is "normal" or "within the range of expectations" or to quit worrying about it. My dealer has invested quite a bit of time on the issue, which says something.
4) The Honda engineers that couldn't have missed this issue are the same engineers that missed CVT coding that allows the transmission to slip at highway speeds (TSB issued), presided over releasing to production an engine/tranmssion combination that allowed excessive slow speed and idle vibration (TSB issued), designed engines that allowed excessive oil consumption in a variety of 4 (rings) and 6 (VCM) cylinder engines, designed a series of failing 4 and 5 speed transmissions, and so on. So I'm not quite ready to anoint this group as among the infallibles.
So I guess I'll keep pursuing the issue and see what happens.
If I understand everything correctly from this thread there are multiple samples with the same level of fuel dilution. It is being considered a "problem" because it is a higher level than traditionally seen. Honda can find nothing wrong with the engine.
First, a blanket statement that x% of fuel dilution will cause issues is flat out wrong. The engine system is designed to operate with a certain level of oil film thickness. Do we really think that Honda engineers haven't encountered similar fuel dilution issues and therefore designed around the know fuel dilution? Unfortunately, only the engineers that developed the engine would have the answer but I think we can see from the wear values that everything is fine.
When fuel dilution becomes an issue the wear values start to skyrocket and there is no mistake that a problem is present. Just because fuel is present does not mean there is a problem if the engine was designed for it.
OP, drive on with confidence.
You may be exactly right; this issue could be my personal "white whale", I might be a happier camper had I never heard of "used oil analysis" or "fuel dilution" and at the end of the day it may mean nothing.
On the other hand:
1) The level of fuel dilution in my example is substantially higher than any other UOA I've seen from a Honda K24W engine
2) Honda USA claims to have never seen another fuel dilution complaint for this engine
3) While Honda can't find anything wrong, they are also not able to tell me that this level is "normal" or "within the range of expectations" or to quit worrying about it. My dealer has invested quite a bit of time on the issue, which says something.
4) The Honda engineers that couldn't have missed this issue are the same engineers that missed CVT coding that allows the transmission to slip at highway speeds (TSB issued), presided over releasing to production an engine/tranmssion combination that allowed excessive slow speed and idle vibration (TSB issued), designed engines that allowed excessive oil consumption in a variety of 4 (rings) and 6 (VCM) cylinder engines, designed a series of failing 4 and 5 speed transmissions, and so on. So I'm not quite ready to anoint this group as among the infallibles.
So I guess I'll keep pursuing the issue and see what happens.
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Originally Posted By: KingCake
Originally Posted By: KrisZ
Switch to 5w30, shorten the OCI to 5k max and keep on trucking. Honda is not going to look at or act on result from a third party oil analysis.
changing to thicker oil is never a proper fix
5w30 is a thin oil. If you're worried about gassing, then you want a higher viscosity oil. No, thicker oil isn't a fix. Rather, it is a delaying action.
Originally Posted By: KrisZ
Switch to 5w30, shorten the OCI to 5k max and keep on trucking. Honda is not going to look at or act on result from a third party oil analysis.
changing to thicker oil is never a proper fix
5w30 is a thin oil. If you're worried about gassing, then you want a higher viscosity oil. No, thicker oil isn't a fix. Rather, it is a delaying action.
Originally Posted By: andyd
Originally Posted By: KingCake
Originally Posted By: KrisZ
Switch to 5w30, shorten the OCI to 5k max and keep on trucking. Honda is not going to look at or act on result from a third party oil analysis.
changing to thicker oil is never a proper fix
5w30 is a thin oil. If you're worried about gassing, then you want a higher viscosity oil. No, thicker oil isn't a fix. Rather, it is a delaying action.
Sure. But as your grin perhaps implies, oil itself is a delaying action. If it wasn't, we wouldn't need to change it.
From a slight bit of skim reading, it seems that compronising long term oil stability is generally more important than viscosity loss.
This is because, while the light fractions of the fuel boil off, the heavy end can accumulate, and is less stable than the oil components and so promotes sludging. This'll probably be more of an issue with diesel, and will be affected by the oil used and the OCI.
Originally Posted By: KingCake
Originally Posted By: KrisZ
Switch to 5w30, shorten the OCI to 5k max and keep on trucking. Honda is not going to look at or act on result from a third party oil analysis.
changing to thicker oil is never a proper fix
5w30 is a thin oil. If you're worried about gassing, then you want a higher viscosity oil. No, thicker oil isn't a fix. Rather, it is a delaying action.
Sure. But as your grin perhaps implies, oil itself is a delaying action. If it wasn't, we wouldn't need to change it.
From a slight bit of skim reading, it seems that compronising long term oil stability is generally more important than viscosity loss.
This is because, while the light fractions of the fuel boil off, the heavy end can accumulate, and is less stable than the oil components and so promotes sludging. This'll probably be more of an issue with diesel, and will be affected by the oil used and the OCI.
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Originally Posted By: Danh
You may be exactly right; this issue could be my personal "white whale", I might be a happier camper had I never heard of "used oil analysis" or "fuel dilution" and at the end of the day it may mean nothing.
On the other hand:
1) The level of fuel dilution in my example is substantially higher than any other UOA I've seen from a Honda K24W engine
2) Honda USA claims to have never seen another fuel dilution complaint for this engine
3) While Honda can't find anything wrong, they are also not able to tell me that this level is "normal" or "within the range of expectations" or to quit worrying about it. My dealer has invested quite a bit of time on the issue, which says something.
4) The Honda engineers that couldn't have missed this issue are the same engineers that missed CVT coding that allows the transmission to slip at highway speeds (TSB issued), presided over releasing to production an engine/tranmssion combination that allowed excessive slow speed and idle vibration (TSB issued), designed engines that allowed excessive oil consumption in a variety of 4 (rings) and 6 (VCM) cylinder engines, designed a series of failing 4 and 5 speed transmissions, and so on. So I'm not quite ready to anoint this group as among the infallibles.
So I guess I'll keep pursuing the issue and see what happens.
Valid points but:
1) The number of engines with UOAs is an extremely small percentage and can't begin to show the range of expected operations.
2) See point 1 for lack of other complaints about fuel dilution.
3) Hardly anyone except the engineers the developed the system will definitively be able to tell you if it is normal or not. It sounds like you have a great dealer and I am very jealous of that.
4) I agree that engineers aren't infallible, myself included. However, fuel dilution is one of the easier issues to test for and uncover during development.
I'm not trying to argue or say you are wrong just attempting to provide the other side of the argument from a perspective that is sometimes hard to get.
You may be exactly right; this issue could be my personal "white whale", I might be a happier camper had I never heard of "used oil analysis" or "fuel dilution" and at the end of the day it may mean nothing.
On the other hand:
1) The level of fuel dilution in my example is substantially higher than any other UOA I've seen from a Honda K24W engine
2) Honda USA claims to have never seen another fuel dilution complaint for this engine
3) While Honda can't find anything wrong, they are also not able to tell me that this level is "normal" or "within the range of expectations" or to quit worrying about it. My dealer has invested quite a bit of time on the issue, which says something.
4) The Honda engineers that couldn't have missed this issue are the same engineers that missed CVT coding that allows the transmission to slip at highway speeds (TSB issued), presided over releasing to production an engine/tranmssion combination that allowed excessive slow speed and idle vibration (TSB issued), designed engines that allowed excessive oil consumption in a variety of 4 (rings) and 6 (VCM) cylinder engines, designed a series of failing 4 and 5 speed transmissions, and so on. So I'm not quite ready to anoint this group as among the infallibles.
So I guess I'll keep pursuing the issue and see what happens.
Valid points but:
1) The number of engines with UOAs is an extremely small percentage and can't begin to show the range of expected operations.
2) See point 1 for lack of other complaints about fuel dilution.
3) Hardly anyone except the engineers the developed the system will definitively be able to tell you if it is normal or not. It sounds like you have a great dealer and I am very jealous of that.
4) I agree that engineers aren't infallible, myself included. However, fuel dilution is one of the easier issues to test for and uncover during development.
I'm not trying to argue or say you are wrong just attempting to provide the other side of the argument from a perspective that is sometimes hard to get.
Originally Posted By: 09_GXP
Originally Posted By: Danh
You may be exactly right; this issue could be my personal "white whale", I might be a happier camper had I never heard of "used oil analysis" or "fuel dilution" and at the end of the day it may mean nothing.
On the other hand:
1) The level of fuel dilution in my example is substantially higher than any other UOA I've seen from a Honda K24W engine
2) Honda USA claims to have never seen another fuel dilution complaint for this engine
3) While Honda can't find anything wrong, they are also not able to tell me that this level is "normal" or "within the range of expectations" or to quit worrying about it. My dealer has invested quite a bit of time on the issue, which says something.
4) The Honda engineers that couldn't have missed this issue are the same engineers that missed CVT coding that allows the transmission to slip at highway speeds (TSB issued), presided over releasing to production an engine/tranmssion combination that allowed excessive slow speed and idle vibration (TSB issued), designed engines that allowed excessive oil consumption in a variety of 4 (rings) and 6 (VCM) cylinder engines, designed a series of failing 4 and 5 speed transmissions, and so on. So I'm not quite ready to anoint this group as among the infallibles.
So I guess I'll keep pursuing the issue and see what happens.
Valid points but:
1) The number of engines with UOAs is an extremely small percentage and can't begin to show the range of expected operations.
2) See point 1 for lack of other complaints about fuel dilution.
3) Hardly anyone except the engineers the developed the system will definitively be able to tell you if it is normal or not. It sounds like you have a great dealer and I am very jealous of that.
4) I agree that engineers aren't infallible, myself included. However, fuel dilution is one of the easier issues to test for and uncover during development.
I'm not trying to argue or say you are wrong just attempting to provide the other side of the argument from a perspective that is sometimes hard to get.
And your points are valid, too. It is hard to accept things like this (did I mention the fuel dilution results in a higher than normal dipstick reading? The horror!) with one's own car though, and the urge to solve a real or perceived problem likely runs strong in the BITOG community.
My dealer has been really good through this, and I'm grateful for that. Unlike many dealers, they don't immediately assume customers with complaints are idiots or potential thieves. But with a bit more time, I may get them there...
Originally Posted By: Danh
You may be exactly right; this issue could be my personal "white whale", I might be a happier camper had I never heard of "used oil analysis" or "fuel dilution" and at the end of the day it may mean nothing.
On the other hand:
1) The level of fuel dilution in my example is substantially higher than any other UOA I've seen from a Honda K24W engine
2) Honda USA claims to have never seen another fuel dilution complaint for this engine
3) While Honda can't find anything wrong, they are also not able to tell me that this level is "normal" or "within the range of expectations" or to quit worrying about it. My dealer has invested quite a bit of time on the issue, which says something.
4) The Honda engineers that couldn't have missed this issue are the same engineers that missed CVT coding that allows the transmission to slip at highway speeds (TSB issued), presided over releasing to production an engine/tranmssion combination that allowed excessive slow speed and idle vibration (TSB issued), designed engines that allowed excessive oil consumption in a variety of 4 (rings) and 6 (VCM) cylinder engines, designed a series of failing 4 and 5 speed transmissions, and so on. So I'm not quite ready to anoint this group as among the infallibles.
So I guess I'll keep pursuing the issue and see what happens.
Valid points but:
1) The number of engines with UOAs is an extremely small percentage and can't begin to show the range of expected operations.
2) See point 1 for lack of other complaints about fuel dilution.
3) Hardly anyone except the engineers the developed the system will definitively be able to tell you if it is normal or not. It sounds like you have a great dealer and I am very jealous of that.
4) I agree that engineers aren't infallible, myself included. However, fuel dilution is one of the easier issues to test for and uncover during development.
I'm not trying to argue or say you are wrong just attempting to provide the other side of the argument from a perspective that is sometimes hard to get.
And your points are valid, too. It is hard to accept things like this (did I mention the fuel dilution results in a higher than normal dipstick reading? The horror!) with one's own car though, and the urge to solve a real or perceived problem likely runs strong in the BITOG community.
My dealer has been really good through this, and I'm grateful for that. Unlike many dealers, they don't immediately assume customers with complaints are idiots or potential thieves. But with a bit more time, I may get them there...
Originally Posted By: Danh
>5% fuel dilution from samples taken immediately after a 400 mile highway trip.
Same result for 3 samples taken at different times. Seems convincing.
How many miles are on the oil before the 400 mile drive?
Is the whole 400 miles one trip, or is it broken up into several pieces?
What speeds are you driving at on the highway during those miles?
Is it all in top gear, or are you shifting a bunch if you hit large traffic jams on the highway?
Is your car n/a, or turbocharged?
It's a curious issue you've stumbled upon.
BC.
>5% fuel dilution from samples taken immediately after a 400 mile highway trip.
Same result for 3 samples taken at different times. Seems convincing.
How many miles are on the oil before the 400 mile drive?
Is the whole 400 miles one trip, or is it broken up into several pieces?
What speeds are you driving at on the highway during those miles?
Is it all in top gear, or are you shifting a bunch if you hit large traffic jams on the highway?
Is your car n/a, or turbocharged?
It's a curious issue you've stumbled upon.
BC.
Looking back at some of your previous posts you have mentioned seeing fuel numbers at 1.9% after a long highway run. This tells me that everything is working as it should and there is no problem. Some modern engines will not have 0 fuel dilution no matter how favorable the run. Don't worry they are built for it, as shown by your low wear numbers. If it were my car, I would run it and not worry about a thing.
FWIW: I'm in a similar situation with my F150, a lot of people here got excited by my UOA with low viscosity and possibly increased wear. I'm still motoring on without a second thought.
FWIW: I'm in a similar situation with my F150, a lot of people here got excited by my UOA with low viscosity and possibly increased wear. I'm still motoring on without a second thought.
Bladecutter and 09_GXp, thanks for the interest.
Let's see:
All the UOAs were done with pretty fresh oil, with samples taken with 1,000 - 2,500 miles on the oil. Never extended an OCI very far as Polaris was pushing the UOA panic button and suggesting an immediate oil change because of the fuel dilution.
The 400 mile trip was nonstop except for one refueling each time and was mostly Interstate with 70-75 mph speeds. No heavy traffic to speak of. In other words, pretty ideal conditions where fuel dilution should be a near zero as it will ever be.
The CRV is naturally aspirated and has a CVT, so no shifting required.
I experimented with fuel grades and the 1.9% was with 93 octane. The 3 with >5% were 87 or 89. Some have found Mazda DI engines benefit from premium and just maybe Hondas are the same. I could continue to run premium, but other K24W UOAs seem to be just fine using the Honda-specified 87 octane. Plus, with the $.70 cost premium for premium in my neck of the woods, I'm a bit disinclined to spend an extra few hundred bucks a year to get the car to perform correctly, though this may be where I eventually wind up.
The CVT works hard to keep revs low, though it will eagerly "downshift" for hills and the like. But maybe this thIng runs on the ragged edge of pre-ignition and richens the mixture a lot and frequently on 87/89 octane fuel.
If so, Honda may have pushed the fuel economy envelope a bit too far.
Such drama...I should probably join 09_GXP and just motor on.
Let's see:
All the UOAs were done with pretty fresh oil, with samples taken with 1,000 - 2,500 miles on the oil. Never extended an OCI very far as Polaris was pushing the UOA panic button and suggesting an immediate oil change because of the fuel dilution.
The 400 mile trip was nonstop except for one refueling each time and was mostly Interstate with 70-75 mph speeds. No heavy traffic to speak of. In other words, pretty ideal conditions where fuel dilution should be a near zero as it will ever be.
The CRV is naturally aspirated and has a CVT, so no shifting required.
I experimented with fuel grades and the 1.9% was with 93 octane. The 3 with >5% were 87 or 89. Some have found Mazda DI engines benefit from premium and just maybe Hondas are the same. I could continue to run premium, but other K24W UOAs seem to be just fine using the Honda-specified 87 octane. Plus, with the $.70 cost premium for premium in my neck of the woods, I'm a bit disinclined to spend an extra few hundred bucks a year to get the car to perform correctly, though this may be where I eventually wind up.
The CVT works hard to keep revs low, though it will eagerly "downshift" for hills and the like. But maybe this thIng runs on the ragged edge of pre-ignition and richens the mixture a lot and frequently on 87/89 octane fuel.
If so, Honda may have pushed the fuel economy envelope a bit too far.
Such drama...I should probably join 09_GXP and just motor on.
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