Fuel Dilution "Burn-Off"
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Originally Posted By: SonofJoe
And another random thought...
I half joked about Honda bolting a 'mini steam stripper' on to their fuel dilution prone engines. Realistically this would be impractical. You would keep a separate distilled water reservoir, have a HP steam generator, a condenser, a fuel/water separator, etc, etc. Too bulky, too costly, not going to happen, ever.
Maybe not, though that'd seem to depend in part on how much steam you'd need. How much would you need?
If water-injection amounts would be useful, then two birds with one stove could perhaps be steamed.
Doing it statically, however, you wouldn't need any of that stuff, but you would then have to supply it with energy, and you'd need to dispose of the fuel you drove off rather than just burning it.
And another random thought...
I half joked about Honda bolting a 'mini steam stripper' on to their fuel dilution prone engines. Realistically this would be impractical. You would keep a separate distilled water reservoir, have a HP steam generator, a condenser, a fuel/water separator, etc, etc. Too bulky, too costly, not going to happen, ever.
Maybe not, though that'd seem to depend in part on how much steam you'd need. How much would you need?
If water-injection amounts would be useful, then two birds with one stove could perhaps be steamed.
Doing it statically, however, you wouldn't need any of that stuff, but you would then have to supply it with energy, and you'd need to dispose of the fuel you drove off rather than just burning it.
Originally Posted By: dblshock
SnoofJoe
In your opinion, could in any way my practice of dosing the fuel with TC-W3 2stroke oil 640:1 have contributed to the fuel dilution issue I'm experiencing?
Here's a link to an old BP patent which provides some info on 2T oil formulations...
https://www.google.com/patents/US5475171
This suggests what you're adding is low molecular weight Poly Iso-Butylene (PIB), heavy mineral oil, a low ash additive pack and 18% KEROSENE diluant!
So directionally, adding 2T oil WILL worsen fuel dilution. What's more, that kerosene is heavier and less volatile than gasoline and will be more resistant to being stripped out by the blow-by and would tend to accumulate in the oil with time as you burn more fuel.
I have to ask, why would you add 2T oil to the fuel of what I'm assuming is a four-stroke engine?
SnoofJoe
In your opinion, could in any way my practice of dosing the fuel with TC-W3 2stroke oil 640:1 have contributed to the fuel dilution issue I'm experiencing?
Here's a link to an old BP patent which provides some info on 2T oil formulations...
https://www.google.com/patents/US5475171
This suggests what you're adding is low molecular weight Poly Iso-Butylene (PIB), heavy mineral oil, a low ash additive pack and 18% KEROSENE diluant!
So directionally, adding 2T oil WILL worsen fuel dilution. What's more, that kerosene is heavier and less volatile than gasoline and will be more resistant to being stripped out by the blow-by and would tend to accumulate in the oil with time as you burn more fuel.
I have to ask, why would you add 2T oil to the fuel of what I'm assuming is a four-stroke engine?
Originally Posted By: dblshock
well it does add lubricity and the total amount is minimal @ 640:1, I have discontinued this in an effort to see if it's adding to the problem..and your valued opinion is that it is...thx.
I'm assuming you're talking about fuel lubricity?? In which case I wouldn't bother if I were you.
The big thing about 2T oils is that they add PIB base oil, heavy mineral oil and a slug of ashless dispersant. As I recall, the PIB is there to 'paint' any soot particles white so exhaust becomes less visible and the heavy base oil and ashless provide something relatively non-volatile to coat the bores with.
The thing is most commercial gasolines will contain additives to prevent inlet valve deposits and these are based on very similar componentry to what you find in 2T. Yes the PIB is heavier and functionalised to neutralised PIBSA but it's close enough. Likewise the additives usually contain a heavy base oil carrier oil to physically 'bash' the top surfaces of the inlet valves.
well it does add lubricity and the total amount is minimal @ 640:1, I have discontinued this in an effort to see if it's adding to the problem..and your valued opinion is that it is...thx.
I'm assuming you're talking about fuel lubricity?? In which case I wouldn't bother if I were you.
The big thing about 2T oils is that they add PIB base oil, heavy mineral oil and a slug of ashless dispersant. As I recall, the PIB is there to 'paint' any soot particles white so exhaust becomes less visible and the heavy base oil and ashless provide something relatively non-volatile to coat the bores with.
The thing is most commercial gasolines will contain additives to prevent inlet valve deposits and these are based on very similar componentry to what you find in 2T. Yes the PIB is heavier and functionalised to neutralised PIBSA but it's close enough. Likewise the additives usually contain a heavy base oil carrier oil to physically 'bash' the top surfaces of the inlet valves.
Originally Posted By: FZ1
Contact Pela to see if they make a tube diameter to fit your Honda. Gonna be a lot of 1.5 turbos out there.
Or visit you local hardware store. As I understand it, extraction tubes for used oil analysis should be one-use only.
Contact Pela to see if they make a tube diameter to fit your Honda. Gonna be a lot of 1.5 turbos out there.
Or visit you local hardware store. As I understand it, extraction tubes for used oil analysis should be one-use only.
Originally Posted By: Ducked
Originally Posted By: SonofJoe
And another random thought...
I half joked about Honda bolting a 'mini steam stripper' on to their fuel dilution prone engines. Realistically this would be impractical. You would keep a separate distilled water reservoir, have a HP steam generator, a condenser, a fuel/water separator, etc, etc. Too bulky, too costly, not going to happen, ever.
If water-injection amounts would be useful, then two birds with one stove could perhaps be steamed.
Second thoughts, Nah. Steam-powered water injection makes sense, but combining it with steam stripping seems likely to be too complicated.
Originally Posted By: SonofJoe
And another random thought...
I half joked about Honda bolting a 'mini steam stripper' on to their fuel dilution prone engines. Realistically this would be impractical. You would keep a separate distilled water reservoir, have a HP steam generator, a condenser, a fuel/water separator, etc, etc. Too bulky, too costly, not going to happen, ever.
If water-injection amounts would be useful, then two birds with one stove could perhaps be steamed.
Second thoughts, Nah. Steam-powered water injection makes sense, but combining it with steam stripping seems likely to be too complicated.
I did visit the hardware store and the only tube I could find was a brass 5/32 that will fit tite inside the mity Vac's 3/16 extractor tube, I bought it 3' for $3.25 now have to glue it together...still have to elongate the brass tube to fit and will use all 3' in case it sticks I'll need to pull it out..stay tuned going in this w/e
Last nite I did find a extractor unit with tiny diameter tubes, Ill go this route if the brass extension fails
extractor link
Last nite I did find a extractor unit with tiny diameter tubes, Ill go this route if the brass extension fails
extractor link
Originally Posted By: dblshock
I did visit the hardware store and the only tube I could find was a brass 5/32 that will fit tite inside the mity Vac's 3/16 extractor tube, I bought it 3' for $3.25 now have to glue it together...still have to elongate the brass tube to fit and will use all 3' in case it sticks I'll need to pull it out..stay tuned going in this w/e
Last nite I did find a extractor unit with tiny diameter tubes, Ill go this route if the brass extension fails
extractor link
You might want to take a look at the Griot's Garage website. I use Griot's fluid extractor and it's a good piece of equipment. Cheaper than what you're looking at, but dunno if the tube diameter is appropriate.
I did visit the hardware store and the only tube I could find was a brass 5/32 that will fit tite inside the mity Vac's 3/16 extractor tube, I bought it 3' for $3.25 now have to glue it together...still have to elongate the brass tube to fit and will use all 3' in case it sticks I'll need to pull it out..stay tuned going in this w/e
Last nite I did find a extractor unit with tiny diameter tubes, Ill go this route if the brass extension fails
extractor link
You might want to take a look at the Griot's Garage website. I use Griot's fluid extractor and it's a good piece of equipment. Cheaper than what you're looking at, but dunno if the tube diameter is appropriate.
Last edited:
Originally Posted By: Onug
So I need an executive summary here. Is the general consensus:
1) Fuel burn-off can happen under the right conditions, but
2) Normal operating temperatures will only allow the more volatile elements (compounds? What's the correct term here?) in the fuel to convert to gas and certain elements will remain behind. Those remaining elements/compounds are technically contaminants.
4) The oil type/weight is not the cause of fuel dilution, but dilution will negatively impact the oil. This impact is most noticeably seen in dropping the oil out of it's specific spec (thinning) and a decrease in the flashpoint.
5) The best way to determine if fuel dilution has reached a point that it's causing damaging is by performing a used oil analysis and looking for elevated wear metals.
6) The used oil analysis should be used to confirm or adjust the nominal oil change interval.
Please adjust/change/correct as needed. This has been a great conversation...and I think a summary is needed.
In addition the the other comments as so as not to alarm readers, the fuel dilution issue is almost exclusively, from direct injection an turbocharged direct injection engines. Traditional port injected engines only suffer from fuel dilution if there's really something wrong, like a bad fuel injector. DI/TGDI engines, on the other hand, seem to have varying degrees of fuel,dilution even if they are working exactly as the factory intended.
So, if you have a car with port fuel injection, don't sweat this too much. If you have a DI/TGDI engine, you may want to get a gas chromotography reading with a used oil analysis. It may not make you happy though...
So I need an executive summary here. Is the general consensus:
1) Fuel burn-off can happen under the right conditions, but
2) Normal operating temperatures will only allow the more volatile elements (compounds? What's the correct term here?) in the fuel to convert to gas and certain elements will remain behind. Those remaining elements/compounds are technically contaminants.
4) The oil type/weight is not the cause of fuel dilution, but dilution will negatively impact the oil. This impact is most noticeably seen in dropping the oil out of it's specific spec (thinning) and a decrease in the flashpoint.
5) The best way to determine if fuel dilution has reached a point that it's causing damaging is by performing a used oil analysis and looking for elevated wear metals.
6) The used oil analysis should be used to confirm or adjust the nominal oil change interval.
Please adjust/change/correct as needed. This has been a great conversation...and I think a summary is needed.
In addition the the other comments as so as not to alarm readers, the fuel dilution issue is almost exclusively, from direct injection an turbocharged direct injection engines. Traditional port injected engines only suffer from fuel dilution if there's really something wrong, like a bad fuel injector. DI/TGDI engines, on the other hand, seem to have varying degrees of fuel,dilution even if they are working exactly as the factory intended.
So, if you have a car with port fuel injection, don't sweat this too much. If you have a DI/TGDI engine, you may want to get a gas chromotography reading with a used oil analysis. It may not make you happy though...
Originally Posted By: Danh
Originally Posted By: Onug
So I need an executive summary here. Is the general consensus:
1) Fuel burn-off can happen under the right conditions, but
2) Normal operating temperatures will only allow the more volatile elements (compounds? What's the correct term here?) in the fuel to convert to gas and certain elements will remain behind. Those remaining elements/compounds are technically contaminants.
4) The oil type/weight is not the cause of fuel dilution, but dilution will negatively impact the oil. This impact is most noticeably seen in dropping the oil out of it's specific spec (thinning) and a decrease in the flashpoint.
5) The best way to determine if fuel dilution has reached a point that it's causing damaging is by performing a used oil analysis and looking for elevated wear metals.
6) The used oil analysis should be used to confirm or adjust the nominal oil change interval.
Please adjust/change/correct as needed. This has been a great conversation...and I think a summary is needed.
In addition the the other comments as so as not to alarm readers, the fuel dilution issue is almost exclusively, from direct injection an turbocharged direct injection engines. Traditional port injected engines only suffer from fuel dilution if there's really something wrong, like a bad fuel injector. DI/TGDI engines, on the other hand, seem to have varying degrees of fuel,dilution even if they are working exactly as the factory intended.
So, if you have a car with port fuel injection, don't sweat this too much. If you have a DI/TGDI engine, you may want to get a gas chromotography reading with a used oil analysis. It may not make you happy though...
Yeah, tell me about it! The only "defense" for what this may be doing to my TGDI engine is to use the right oil and fuel along with a "severe service" short OCI. In my case, I also have a very effective OCC installed on the PCV system (which catches ~2oz of fluid gunk per 2~3K miles) for my DD.
Originally Posted By: Onug
So I need an executive summary here. Is the general consensus:
1) Fuel burn-off can happen under the right conditions, but
2) Normal operating temperatures will only allow the more volatile elements (compounds? What's the correct term here?) in the fuel to convert to gas and certain elements will remain behind. Those remaining elements/compounds are technically contaminants.
4) The oil type/weight is not the cause of fuel dilution, but dilution will negatively impact the oil. This impact is most noticeably seen in dropping the oil out of it's specific spec (thinning) and a decrease in the flashpoint.
5) The best way to determine if fuel dilution has reached a point that it's causing damaging is by performing a used oil analysis and looking for elevated wear metals.
6) The used oil analysis should be used to confirm or adjust the nominal oil change interval.
Please adjust/change/correct as needed. This has been a great conversation...and I think a summary is needed.
In addition the the other comments as so as not to alarm readers, the fuel dilution issue is almost exclusively, from direct injection an turbocharged direct injection engines. Traditional port injected engines only suffer from fuel dilution if there's really something wrong, like a bad fuel injector. DI/TGDI engines, on the other hand, seem to have varying degrees of fuel,dilution even if they are working exactly as the factory intended.
So, if you have a car with port fuel injection, don't sweat this too much. If you have a DI/TGDI engine, you may want to get a gas chromotography reading with a used oil analysis. It may not make you happy though...
Yeah, tell me about it! The only "defense" for what this may be doing to my TGDI engine is to use the right oil and fuel along with a "severe service" short OCI. In my case, I also have a very effective OCC installed on the PCV system (which catches ~2oz of fluid gunk per 2~3K miles) for my DD.
Originally Posted By: SonofJoe
I half joked about Honda bolting a 'mini steam stripper' on to their fuel dilution prone engines. Realistically this would be impractical. You would keep a separate distilled water reservoir, have a HP steam generator, a condenser, a fuel/water separator, etc, etc. Too bulky, too costly, not going to happen, ever.
Most of these requirements (and the fuel dilution problem itself) seem to be mitigatable by running at a higher temperature. Other than "safety margin" I'm puzzling to come up with a reason why the coolant and oil isn't run hotter.
Perhaps you'd need higher viscosity oil which would make preheating necessary for cold starts?
Specifically:-
Separate distilled water reservoir doesn't seem like too big a deal, depending on your location. Aircon condensate is available for free in huge quantities and is essentially distilled water. Such a system wouldn't necessarily have to operate continuously so a limited capacity might be acceptable.
An HP steam generator doesn't seem like too big a deal either. IF the coolant was running at, say 120C, which should be achievable with current systems, a separate coolant-heated boiler at a lower pressure could produce steam at say 110C. IF the sump oil was over 100 this steam would not condense in it. Higher pressure rad caps are available which implies there must be some scope to increase pressures on standard systems, though large increases would presumably require a stronger (and therefore heavier) system.
A condenser/fuel water separator seems potentially optional, since you can probably just burn the steam and stripped hydrocarbons in the engine (as is done with blowby currently).
A condenser might be necessary for water recovery for continuous operation, but continuous operation might not be required.
If the stripping increases oil carry over and intake tract coking (which the steam might be expected to somewhat mitigate), you could have a catch can/fuel/water separator arrangement, but then you have an environmental disposal problem.
The main problem for running a total loss system would be convincing the punter to top it up. I believe that's largely what killed the mass-market water injection on the 1962 Oldsmobile F-85 turbo.
Originally Posted By: SonofJoe
You obviously couldn't put the entire sump under vacuum.
Er...my entire sump is under vacuum, and I think this is normal.
I think you generally only get positive crankcase pressure at high power/boost levels when the blowby exceeds the capacity of the crankcase ventilation system.
Your description sounds, at least qualitatively, like normal operation, except for the gassing of the (presumably bulk sump oil) with air or blowby, which AFAIK is not done, though I think the oil spray is in effect purged in this way.
Perhaps its a question of degree, and you propose enhancing the vacuum or increasing the capacity of the crankcase ventilation system?
I suppose you could also increase the amount of oil fling, which might be simpler than pumping gas through the bulk oil. Either way you'd have to be sure to avoid foam.
I half joked about Honda bolting a 'mini steam stripper' on to their fuel dilution prone engines. Realistically this would be impractical. You would keep a separate distilled water reservoir, have a HP steam generator, a condenser, a fuel/water separator, etc, etc. Too bulky, too costly, not going to happen, ever.
Most of these requirements (and the fuel dilution problem itself) seem to be mitigatable by running at a higher temperature. Other than "safety margin" I'm puzzling to come up with a reason why the coolant and oil isn't run hotter.
Perhaps you'd need higher viscosity oil which would make preheating necessary for cold starts?
Specifically:-
Separate distilled water reservoir doesn't seem like too big a deal, depending on your location. Aircon condensate is available for free in huge quantities and is essentially distilled water. Such a system wouldn't necessarily have to operate continuously so a limited capacity might be acceptable.
An HP steam generator doesn't seem like too big a deal either. IF the coolant was running at, say 120C, which should be achievable with current systems, a separate coolant-heated boiler at a lower pressure could produce steam at say 110C. IF the sump oil was over 100 this steam would not condense in it. Higher pressure rad caps are available which implies there must be some scope to increase pressures on standard systems, though large increases would presumably require a stronger (and therefore heavier) system.
A condenser/fuel water separator seems potentially optional, since you can probably just burn the steam and stripped hydrocarbons in the engine (as is done with blowby currently).
A condenser might be necessary for water recovery for continuous operation, but continuous operation might not be required.
If the stripping increases oil carry over and intake tract coking (which the steam might be expected to somewhat mitigate), you could have a catch can/fuel/water separator arrangement, but then you have an environmental disposal problem.
The main problem for running a total loss system would be convincing the punter to top it up. I believe that's largely what killed the mass-market water injection on the 1962 Oldsmobile F-85 turbo.
Originally Posted By: SonofJoe
You obviously couldn't put the entire sump under vacuum.
Er...my entire sump is under vacuum, and I think this is normal.
I think you generally only get positive crankcase pressure at high power/boost levels when the blowby exceeds the capacity of the crankcase ventilation system.
Your description sounds, at least qualitatively, like normal operation, except for the gassing of the (presumably bulk sump oil) with air or blowby, which AFAIK is not done, though I think the oil spray is in effect purged in this way.
Perhaps its a question of degree, and you propose enhancing the vacuum or increasing the capacity of the crankcase ventilation system?
I suppose you could also increase the amount of oil fling, which might be simpler than pumping gas through the bulk oil. Either way you'd have to be sure to avoid foam.
Originally Posted By: Ducked
Originally Posted By: SonofJoe
I half joked about Honda bolting a 'mini steam stripper' on to their fuel dilution prone engines. Realistically this would be impractical. You would keep a separate distilled water reservoir, have a HP steam generator, a condenser, a fuel/water separator, etc, etc. Too bulky, too costly, not going to happen, ever.
Most of these requirements (and the fuel dilution problem itself) seem to be mitigatable by running at a higher temperature. Other than "safety margin" I'm puzzling to come up with a reason why the coolant and oil isn't run hotter.
The temperature issue is a puzzler. My DI Ford, which isn't a fuel diluter, has a 190F thermostat. My DI Honda, which is, has a 172F. Other factors are certainly at play, but it is interesting that Honda increased the thermostat temperature on the 2016 Accord with the same engine by 5C/9F. May be Honda's way of sort-of trying to deal with the issue. Cheap, too. And if it's "harmless", why bother?
Originally Posted By: SonofJoe
I half joked about Honda bolting a 'mini steam stripper' on to their fuel dilution prone engines. Realistically this would be impractical. You would keep a separate distilled water reservoir, have a HP steam generator, a condenser, a fuel/water separator, etc, etc. Too bulky, too costly, not going to happen, ever.
Most of these requirements (and the fuel dilution problem itself) seem to be mitigatable by running at a higher temperature. Other than "safety margin" I'm puzzling to come up with a reason why the coolant and oil isn't run hotter.
The temperature issue is a puzzler. My DI Ford, which isn't a fuel diluter, has a 190F thermostat. My DI Honda, which is, has a 172F. Other factors are certainly at play, but it is interesting that Honda increased the thermostat temperature on the 2016 Accord with the same engine by 5C/9F. May be Honda's way of sort-of trying to deal with the issue. Cheap, too. And if it's "harmless", why bother?
Last edited:
Originally Posted By: Ducked
Originally Posted By: SonofJoe
I half joked about Honda bolting a 'mini steam stripper' on to their fuel dilution prone engines. Realistically this would be impractical. You would keep a separate distilled water reservoir, have a HP steam generator, a condenser, a fuel/water separator, etc, etc. Too bulky, too costly, not going to happen, ever.
Most of these requirements (and the fuel dilution problem itself) seem to be mitigatable by running at a higher temperature. Other than "safety margin" I'm puzzling to come up with a reason why the coolant and oil isn't run hotter.
Perhaps you'd need higher viscosity oil which would make preheating necessary for cold starts?
Specifically:-
Separate distilled water reservoir doesn't seem like too big a deal, depending on your location. Aircon condensate is available for free in huge quantities and is essentially distilled water. Such a system wouldn't necessarily have to operate continuously so a limited capacity might be acceptable.
An HP steam generator doesn't seem like too big a deal either. IF the coolant was running at, say 120C, which should be achievable with current systems, a separate coolant-heated boiler at a lower pressure could produce steam at say 110C. IF the sump oil was over 100 this steam would not condense in it. Higher pressure rad caps are available which implies there must be some scope to increase pressures on standard systems, though large increases would presumably require a stronger (and therefore heavier) system.
A condenser/fuel water separator seems potentially optional, since you can probably just burn the steam and stripped hydrocarbons in the engine (as is done with blowby currently).
A condenser might be necessary for water recovery for continuous operation, but continuous operation might not be required.
If the stripping increases oil carry over and intake tract coking (which the steam might be expected to somewhat mitigate), you could have a catch can/fuel/water separator arrangement, but then you have an environmental disposal problem.
The main problem for running a total loss system would be convincing the punter to top it up. I believe that's largely what killed the mass-market water injection on the 1962 Oldsmobile F-85 turbo.
Originally Posted By: SonofJoe
You obviously couldn't put the entire sump under vacuum.
Er...my entire sump is under vacuum, and I think this is normal.
I think you generally only get positive crankcase pressure at high power/boost levels when the blowby exceeds the capacity of the crankcase ventilation system.
Your description sounds, at least qualitatively, like normal operation, except for the gassing of the (presumably bulk sump oil) with air or blowby, which AFAIK is not done, though I think the oil spray is in effect purged in this way.
Perhaps its a question of degree, and you propose enhancing the vacuum or increasing the capacity of the crankcase ventilation system?
I suppose you could also increase the amount of oil fling, which might be simpler than pumping gas through the bulk oil. Either way you'd have to be sure to avoid foam.
exhaust gas is hotter than 120°C by a big margin. and available in large quantities...
Originally Posted By: SonofJoe
I half joked about Honda bolting a 'mini steam stripper' on to their fuel dilution prone engines. Realistically this would be impractical. You would keep a separate distilled water reservoir, have a HP steam generator, a condenser, a fuel/water separator, etc, etc. Too bulky, too costly, not going to happen, ever.
Most of these requirements (and the fuel dilution problem itself) seem to be mitigatable by running at a higher temperature. Other than "safety margin" I'm puzzling to come up with a reason why the coolant and oil isn't run hotter.
Perhaps you'd need higher viscosity oil which would make preheating necessary for cold starts?
Specifically:-
Separate distilled water reservoir doesn't seem like too big a deal, depending on your location. Aircon condensate is available for free in huge quantities and is essentially distilled water. Such a system wouldn't necessarily have to operate continuously so a limited capacity might be acceptable.
An HP steam generator doesn't seem like too big a deal either. IF the coolant was running at, say 120C, which should be achievable with current systems, a separate coolant-heated boiler at a lower pressure could produce steam at say 110C. IF the sump oil was over 100 this steam would not condense in it. Higher pressure rad caps are available which implies there must be some scope to increase pressures on standard systems, though large increases would presumably require a stronger (and therefore heavier) system.
A condenser/fuel water separator seems potentially optional, since you can probably just burn the steam and stripped hydrocarbons in the engine (as is done with blowby currently).
A condenser might be necessary for water recovery for continuous operation, but continuous operation might not be required.
If the stripping increases oil carry over and intake tract coking (which the steam might be expected to somewhat mitigate), you could have a catch can/fuel/water separator arrangement, but then you have an environmental disposal problem.
The main problem for running a total loss system would be convincing the punter to top it up. I believe that's largely what killed the mass-market water injection on the 1962 Oldsmobile F-85 turbo.
Originally Posted By: SonofJoe
You obviously couldn't put the entire sump under vacuum.
Er...my entire sump is under vacuum, and I think this is normal.
I think you generally only get positive crankcase pressure at high power/boost levels when the blowby exceeds the capacity of the crankcase ventilation system.
Your description sounds, at least qualitatively, like normal operation, except for the gassing of the (presumably bulk sump oil) with air or blowby, which AFAIK is not done, though I think the oil spray is in effect purged in this way.
Perhaps its a question of degree, and you propose enhancing the vacuum or increasing the capacity of the crankcase ventilation system?
I suppose you could also increase the amount of oil fling, which might be simpler than pumping gas through the bulk oil. Either way you'd have to be sure to avoid foam.
exhaust gas is hotter than 120°C by a big margin. and available in large quantities...
Originally Posted By: Danh
Originally Posted By: Ducked
Originally Posted By: SonofJoe
I half joked about Honda bolting a 'mini steam stripper' on to their fuel dilution prone engines. Realistically this would be impractical. You would keep a separate distilled water reservoir, have a HP steam generator, a condenser, a fuel/water separator, etc, etc. Too bulky, too costly, not going to happen, ever.
Most of these requirements (and the fuel dilution problem itself) seem to be mitigatable by running at a higher temperature. Other than "safety margin" I'm puzzling to come up with a reason why the coolant and oil isn't run hotter.
The temperature issue is a puzzler. My DI Ford, which isn't a fuel diluter, has a 190F thermostat. My DI Honda, which is, has a 172F. Other factors are certainly at play, but it is interesting that Honda increased the thermostat temperature on the 2016 Accord with the same engine by 5C/9F. May be Honda's way of sort-of trying to deal with the issue. Cheap, too. And if it's "harmless", why bother?
I'm guessing the newer engine is more fuel efficient. Increasing the thermostat temperature means less heat will be stripped from the cilinders and efficiency goes up. It's not without risk though, as detonation becomes more likely and the valves + seats will get signiicantly hotter and possibly wear more early.
Originally Posted By: Ducked
Originally Posted By: SonofJoe
I half joked about Honda bolting a 'mini steam stripper' on to their fuel dilution prone engines. Realistically this would be impractical. You would keep a separate distilled water reservoir, have a HP steam generator, a condenser, a fuel/water separator, etc, etc. Too bulky, too costly, not going to happen, ever.
Most of these requirements (and the fuel dilution problem itself) seem to be mitigatable by running at a higher temperature. Other than "safety margin" I'm puzzling to come up with a reason why the coolant and oil isn't run hotter.
The temperature issue is a puzzler. My DI Ford, which isn't a fuel diluter, has a 190F thermostat. My DI Honda, which is, has a 172F. Other factors are certainly at play, but it is interesting that Honda increased the thermostat temperature on the 2016 Accord with the same engine by 5C/9F. May be Honda's way of sort-of trying to deal with the issue. Cheap, too. And if it's "harmless", why bother?
I'm guessing the newer engine is more fuel efficient. Increasing the thermostat temperature means less heat will be stripped from the cilinders and efficiency goes up. It's not without risk though, as detonation becomes more likely and the valves + seats will get signiicantly hotter and possibly wear more early.
Originally Posted By: Jetronic
Originally Posted By: Danh
Originally Posted By: Ducked
Originally Posted By: SonofJoe
I half joked about Honda bolting a 'mini steam stripper' on to their fuel dilution prone engines. Realistically this would be impractical. You would keep a separate distilled water reservoir, have a HP steam generator, a condenser, a fuel/water separator, etc, etc. Too bulky, too costly, not going to happen, ever.
Most of these requirements (and the fuel dilution problem itself) seem to be mitigatable by running at a higher temperature. Other than "safety margin" I'm puzzling to come up with a reason why the coolant and oil isn't run hotter.
The temperature issue is a puzzler. My DI Ford, which isn't a fuel diluter, has a 190F thermostat. My DI Honda, which is, has a 172F. Other factors are certainly at play, but it is interesting that Honda increased the thermostat temperature on the 2016 Accord with the same engine by 5C/9F. May be Honda's way of sort-of trying to deal with the issue. Cheap, too. And if it's "harmless", why bother?
I'm guessing the newer engine is more fuel efficient. Increasing the thermostat temperature means less heat will be stripped from the cilinders and efficiency goes up. It's not without risk though, as detonation becomes more likely and the valves + seats will get signiicantly hotter and possibly wear more early.
The 2016/17!Accord engine is the same K24W that powers the 2013-15 Accord and the 2015-16 CRV. The 2018 Accord will have new engines, presumably 1.5 and 2.0 TGDI versions.
Originally Posted By: Danh
Originally Posted By: Ducked
Originally Posted By: SonofJoe
I half joked about Honda bolting a 'mini steam stripper' on to their fuel dilution prone engines. Realistically this would be impractical. You would keep a separate distilled water reservoir, have a HP steam generator, a condenser, a fuel/water separator, etc, etc. Too bulky, too costly, not going to happen, ever.
Most of these requirements (and the fuel dilution problem itself) seem to be mitigatable by running at a higher temperature. Other than "safety margin" I'm puzzling to come up with a reason why the coolant and oil isn't run hotter.
The temperature issue is a puzzler. My DI Ford, which isn't a fuel diluter, has a 190F thermostat. My DI Honda, which is, has a 172F. Other factors are certainly at play, but it is interesting that Honda increased the thermostat temperature on the 2016 Accord with the same engine by 5C/9F. May be Honda's way of sort-of trying to deal with the issue. Cheap, too. And if it's "harmless", why bother?
I'm guessing the newer engine is more fuel efficient. Increasing the thermostat temperature means less heat will be stripped from the cilinders and efficiency goes up. It's not without risk though, as detonation becomes more likely and the valves + seats will get signiicantly hotter and possibly wear more early.
The 2016/17!Accord engine is the same K24W that powers the 2013-15 Accord and the 2015-16 CRV. The 2018 Accord will have new engines, presumably 1.5 and 2.0 TGDI versions.
Originally Posted By: Danh
... My DI Honda, which is, has a 172F. ...
Why? That's unusually low, compared to thermostats in most engines of the past 45+ years.
... My DI Honda, which is, has a 172F. ...
Why? That's unusually low, compared to thermostats in most engines of the past 45+ years.
Originally Posted By: CR94
Originally Posted By: Danh
... My DI Honda, which is, has a 172F. ...
Why? That's unusually low, compared to thermostats in most engines of the past 45+ years.
Probably what they've been using for eons. Good Honda engineering: convert an existing engine to DI but don't consider changing things like thermostats. Or the oil life monitor algorithms. On the plus side, extra fuel in the oil should reduce intake valve deposits...
Originally Posted By: Danh
... My DI Honda, which is, has a 172F. ...
Why? That's unusually low, compared to thermostats in most engines of the past 45+ years.
Probably what they've been using for eons. Good Honda engineering: convert an existing engine to DI but don't consider changing things like thermostats. Or the oil life monitor algorithms. On the plus side, extra fuel in the oil should reduce intake valve deposits...
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