2018 CRV 40.1k mi // M1 EP HM 5W30 1.6k mi - Fuel Dilution Bonanza!

[himemsys]

Okay. Let me preface this. I intentionally did an OCI for the four coldest months of the year (11/17 - 3/17), where fuel dilution is at its worst. I *expected* astronomically high fuel dilution. My theory is, if I can bottle up the worst of the fuel dilution in the coldest months of the year, then the OCI for the other 8 months will have much less fuel dilution, because almost none of the cold weather fuel dilution in the oil will carry over to the warm weather OCI. That theory will be tested next November when I change the oil next in this vehicle.

Also, this turbo charged direct injection engine has probably the worst driving pattern it can have. We live in a climate where winters are typically in the 20s-40s. It is common to get about 5 days per year at or below zero degrees Fahrenheit. My wife drives it 1 mi to and from work, with short trips of 3 mi or less very common, as we live in a small town. Every once in awhile, we will take a 50 mi trip to the big city, but those are few and far between. It's probably the worst driving conditions possible for such a fuel-diluting engine. So, behold:

Honestly, the viscosity dropped less then expected. This oil starts at 10.3 cSt and ended at 8.3. Not bad for >5% fuel. The TBN is lower than expected for the mileage, and iron, aluminum, copper, and lead are higher than average. Silicon seems better than before (I changed the air filter back to Honda OEM prior to this OC). Oxidation has climbed from a virgin value of 8 to 12, which is pretty minimal. The oil had plenty of life left, but like I said, I wanted to get the winter oil out come spring so the oil that goes in will have a better chance of lower fuel dilution during the warm 8 months to follow.

The wear metals are low, because of the low mileage. But on a per-mile basis, they're actually slightly worse than the previous OCI (see row highlighted yellow, with previous OCI 11.99ppm per 1000 mi vs this OCI 15.26ppm):

The oil that replaced the M1 EP HM 5W30 is Castrol Edge Euro 5W40 (API SP), along with a new Fram Ultra filter. This pairing will run for the next 8 months. Wish her luck! LOL

 

[cptbarkey]

If only gas had at least some lubricating qualities. My condolences. Thank you for the oratory.

 

[camrydriver111]

Nice reports. Thanks for sharing.

Interesting to see how quickly the short trips eat the TBN, so going with a Euro oil is a good call imo.

 

[SatinSilver]

Thank you for sharing and good point cutting the interval to four months.

 

[fantastic]

She's got some gas...and it's critical...#4.
Good call on OEM filter & going to a 40 grade oil. Like you mention the viscosity seems to be ok for this very short run & more fuel is needed in cold weather so your position has merit. More fuel could mean more fuel pushing past the rings. I think this result shows the fuel at least a bit higher than the last test so it's looking like things are going as planned so far. I like how you explained everything here in your post. Great job & good luck!

 

[JavierH19]

Viscosity is higher than I expected for a 10-11 cst 5w-30 with 4.4% dilution, wasn't used long enough to oxidize to counter the thinning. I guess you could use 0w-40 for the colder part of the year but i think it's fine either way. You don't do extended drains with it.

 

[Klutch9]

Okay. Let me preface this. I intentionally did an OCI for the four coldest months of the year (11/17 - 3/17), where fuel dilution is at its worst. I *expected* astronomically high fuel dilution. My theory is, if I can bottle up the worst of the fuel dilution in the coldest months of the year, then the OCI for the other 8 months will have much less fuel dilution, because almost none of the cold weather fuel dilution in the oil will carry over to the warm weather OCI. That theory will be tested next November when I change the oil next in this vehicle.

Also, this turbo charged direct injection engine has probably the worst driving pattern it can have. We live in a climate where winters are typically in the 20s-40s. It is common to get about 5 days per year at or below zero degrees Fahrenheit. My wife drives it 1 mi to and from work, with short trips of 3 mi or less very common, as we live in a small town. Every once in awhile, we will take a 50 mi trip to the big city, but those are few and far between. It's probably the worst driving conditions possible for such a fuel-diluting engine. So, behold:
View attachment 209578

Honestly, the viscosity dropped less then expected. This oil starts at 10.3 cSt and ended at 8.3. Not bad for >5% fuel. The TBN is lower than expected for the mileage, and iron, aluminum, copper, and lead are higher than average. Silicon seems better than before (I changed the air filter back to Honda OEM prior to this OC). Oxidation has climbed from a virgin value of 8 to 12, which is pretty minimal. The oil had plenty of life left, but like I said, I wanted to get the winter oil out come spring so the oil that goes in will have a better chance of lower fuel dilution during the warm 8 months to follow.

The wear metals are low, because of the low mileage. But on a per-mile basis, they're actually slightly worse than the previous OCI (see row highlighted yellow, with previous OCI 11.99ppm per 1000 mi vs this OCI 15.26ppm):
View attachment 209580

The oil that replaced the M1 EP HM 5W30 is Castrol Edge Euro 5W40 (API SP), along with a new Fram Ultra filter. This pairing will run for the next 8 months. Wish her luck! LOL

I also use Euro oils in our Explorer 2.3 GTDI. We do lots of short trips, in the cold, with the occasional longer trip here and there. Oil definitely has a fuel smell at all times I limit the OCI to around 5,000 miles. Never had a UOA done, but I can only assume that the fuel dilution I know is present isn’t great.

 

[daves87rs]

Not bad at all!

 

[himemsys]

Here is a hint at what >5% fuel might actually be:

When I started this OCI, I put 3.5qt in, which got the oil level to 15mm above the low mark. Just prior to changing the oil, the oil level had climbed to 20mm above the low mark. I know the sump shape can affect this and it's not linear, but that is still very significant.

I measured how much oil was drained and it was only about 3.7qt, but I also know what comes out is never as much as what went in, so that's not quite telling either. My conservative guess was around 10% fuel dilution, with the potential of close to 20%.

For this OCI, I also put in 3.5 qt. Capacity according to Honda is 3.7 qt, but I intentionally underfill it slightly so it's easier to see on the dipstick. The distance between the low and high mark on the dipstick is 17mm, so it's only 2mm below the high mark.

 

[KEVINK0000]

Lots of metal for such a short OCI and very small aluminum engine. If this was mine, (and I was keeping it 250-350k like our other cars here), and short tripped like this in winter, I’d be on 5/30 ST oil and change at 1k, or even less. I think you have found the point where fuel dilution affects lubrication and shortens life. This is like turbo rotary dilution. I think your idea of concentrating the bad OCI and isolating it is good.

 

[twX]

If the viscosity dropped from 10.3 to 8.3 cST, the oil would have around 8% fuel dilution, assuming no shear-thinning.

When looking at iron/1k miles, it can be important to keep in mind how much iron remained in the old oil that is not drained when the oil was changed, especially if you do a very short OCI after a longer one. The remaining oil is typically ~15% of the total oil in the engine. So over the latest OCI, the oil would have increased from 4.5 ppm to 14 ppm. If the previous OCI also started at 4.5 ppm, it increased from 4.5 to 29 ppm.

The iron/1k miles would be 5.4 ppm for the first UOA, and 6.0 ppm for the latest OCI. So, the higher fuel dilution and colder weather didn't cause an obvious increase in iron wear. Though, the 3ppm lead might indicate more bearing wear.

I'd strongly consider installing a block heater on this car. It'll reduce fuel dilution, and the oil will warm up faster, which will help water and fuel evaporate from the crankcase. It should also help with TBN retention of the oil, and allow you to extend your OCIs. Improved fuel economy and longer OCIs will mostly or completely offset the electricity cost. It should also greatly reduce piston ring and liner wear on a short-tripped engine, whether there is fuel dilution or not.

 

[himemsys]

Good call on OEM filter & going to a 40 grade oil. Like you mention the viscosity seems to be ok for this very short run & more fuel is needed in cold weather so your position has merit. More fuel could mean more fuel pushing past the rings. I think this result shows the fuel at least a bit higher than the last test so it's looking like things are going as planned so far.

I once read on here a suggestion that perhaps a higher viscosity oil will provide more of a barrier for fuel pushing past the rings, thus helping reduce fuel dilution. I'm not sure, but it can't hurt.

Viscosity is higher than I expected for a 10-11 cst 5w-30 with 4.4% dilution, wasn't used long enough to oxidize to counter the thinning. I guess you could use 0w-40 for the colder part of the year but i think it's fine either way.

I had that thought, but I think I will stick with 5W40 next winter. The coldest we've ever gotten in my town is -20F and that was maybe twice in 10 years. That is well within 5W40 specs.

If the viscosity dropped from 10.3 to 8.3 cST, the oil would have around 8% fuel dilution, assuming no shear-thinning.

Interesting. So if I'm understanding correctly, you're saying it can't have been anymore than 8%, which puts the fuel somewhere between 5%-8%. I believe that.

When looking at iron/1k miles, it can be important to keep in mind how much iron remained in the old oil that is not drained when the oil was changed, especially if you do a very short OCI after a longer one. The remaining oil is typically ~15% of the total oil in the engine. So over the latest OCI, the oil would have increased from 4.5 ppm to 14 ppm. If the previous OCI also started at 4.5 ppm, it increased from 4.5 to 29 ppm.

The iron/1k miles would be 5.4 ppm for the first UOA, and 6.0 ppm for the latest OCI. So, the higher fuel dilution and colder weather didn't cause an obvious increase in iron wear. Though, the 3ppm lead might indicate more bearing wear.

Interesting analysis. Thank you! For the record, this vehicle has seen very low metal wear in its life. My wife's 1 mile work commute started a little over a year ago and in that time, the vehicle averages less than 14 miles per day, with total wear metals of 12-15ppm per 1000 miles.

Our last big road trip in 2022 saw 4264 mi in 140 days, for an average of 30.5 mi per day. That OCI saw total wear metals at 2.6ppm per 1000 miles.

Previous to that, the vehicle averaged about 20 mi per day and total wear metals at that time were around 6.5ppm per 1000 miles.

That's probably the biggest trend: More miles per day equals less fuel% and lower wear metals. What that might mean is if my wife continues driving <14 mi per day, it won't really matter whether I use thicker oil, higher octane, or isolate the winter driving to it's own oil change interval. Yes, all those things will help, but it won't get me back to 2.6ppm per 1000 mi wear metals. LOL. My hope is come next November, the car will drop back to ~3.5% fuel and ~8ppm total metals per 1000 mi.

 

[football]

Car is used daily for 1 mile short trips and you put a 40 weight oil in it. Makes perfect sense.

 

[himemsys]

Car is used daily for 1 mile short trips and you put a 40 weight oil in it. Makes perfect sense.

I'm not worried about cold flow. That's what the 5W is for.

FWIW The European owner manual for the 2018 CRV lists 5W40 as an acceptable grade.

 

[ARB1977]

Back when we had our 18 crv. I always ran Amsoil SS 0W20 and followed the olm. At the 20K mark I measured the fuel dilution. 1.5 additional qrts came out give or take. We got rid of it for a 19 Pilot only because the wife want a bigger suv.

 

[4strokes]

If the viscosity dropped from 10.3 to 8.3 cST, the oil would have around 8% fuel dilution, assuming no shear-thinning.

When looking at iron/1k miles, it can be important to keep in mind how much iron remained in the old oil that is not drained when the oil was changed, especially if you do a very short OCI after a longer one. The remaining oil is typically ~15% of the total oil in the engine. So over the latest OCI, the oil would have increased from 4.5 ppm to 14 ppm. If the previous OCI also started at 4.5 ppm, it increased from 4.5 to 29 ppm.

The iron/1k miles would be 5.4 ppm for the first UOA, and 6.0 ppm for the latest OCI. So, the higher fuel dilution and colder weather didn't cause an obvious increase in iron wear. Though, the 3ppm lead might indicate more bearing wear.

I'd strongly consider installing a block heater on this car. It'll reduce fuel dilution, and the oil will warm up faster, which will help water and fuel evaporate from the crankcase. It should also help with TBN retention of the oil, and allow you to extend your OCIs. Improved fuel economy and longer OCIs will mostly or completely offset the electricity cost. It should also greatly reduce piston ring and liner wear on a short-tripped engine, whether there is fuel dilution or not.

I also have a CRV I wonder if insulating the foot-long heater hoses would bring the engine up to temperature any faster. I do put the transmission in sport mode on cold mornings which is effective in getting heat faster.

 

[himemsys]

I also have a CRV I wonder if insulating the foot-long heater hoses would bring the engine up to temperature any faster. I do put the transmission in sport mode on cold mornings which is effective in getting heat faster.

Since my wife drives our CRV, there's no way I'm going to get her to change her routine, so sport mode on cold mornings will never happen. LOL I tried to get her to take a longer route to and from work (make her 2 minute drive a 5-7 minute commute) and that was a hard no. The one thing I did get her to start doing is use 91 octane. It took several times of either filling it up myself, or reminding her repeatedly. But now if she happens to fill the car up, she knows to use 91.

 

[SammyChevelleTypeS3]

Since my wife drives our CRV, there's no way I'm going to get her to change her routine, so sport mode on cold mornings will never happen. LOL I tried to get her to take a longer route to and from work (make her 2 minute drive a 5-7 minute commute) and that was a hard no. The one thing I did get her to start doing is use 91 octane. It took several times of either filling it up myself, or reminding her repeatedly. But now if she happens to fill the car up, she knows to use 91.

LoL! Me too..... About the ONLY thing I could get the wife to agree to do is she finally gave in and accepted that she will use the
top tier 91 octane fuel. I cant win though since I can not keep as close an eye on her vehicles as much as I used to.
I am in shock latley. After riding in car with her driving me for first times in years! YIKES. Since she has been driving me back and forth to Doctors , hospital etc.... the last few months so my eyes have really been opened. Me and sons used to always joke and tell her stuff like "take it easy on those roads now and keep it between the ditches Richard Petty" or "the police have their hands full already so please give em a break." as she would leave the house.... Since (at one time or another over the years she has actually backed into and hit both of their vehicles) in the driveway when they still lived at home! Now it seems our comments & prayers for her safety behind the wheel were not in vain. I now KNOW for a fact JESUS has to be her co-pilot.
I can't get over how tough she is on vehicles as we get older the way she drives them. She has to be protected from above to not have a glove box full of tickets or bunch of fender benders. OMG. If there is a rule to the road.... like dont cross this line or these merge lanes starts here or use the passing lane for passing ONLY!! etc.... she will do the exact opposite almost as if to show she is going to do what she wants. At least she does respect red lights and stop signs. Gotta say though I just about have whiplash from all of those jack rabbit take offs and brake slams plus jumps over speed bumps etc... I know I just need to keep comments on her driving to myself and be thankful I am blessed to have her to do all she does to take care of me while working a full time job. Have a couple elderly friends with health issues who are either divorced or simply have no family living close enough to help them (when I cant) so I realize just how lucky I am. I know and bet both men and women on here can tell some very similar stories about their spouses driving etc...

 

[BMWTurboDzl]

LoL! Me too..... About the ONLY thing I could get the wife to agree to do is she finally gave in and accepted that she will use the
top tier 91 octane fuel. I cant win though since I can not keep as close an eye on her vehicles as much as I used to.
I am in shock latley. After riding in car with her driving me for first times in years! YIKES. Since she has been driving me back and forth to Doctors , hospital etc.... the last few months so my eyes have really been opened. Me and sons used to always joke and tell her stuff like "take it easy on those roads now and keep it between the ditches Richard Petty" or "the police have their hands full already so please give em a break." as she would leave the house.... Since (at one time or another over the years she has actually backed into and hit both of their vehicles) in the driveway when they still lived at home! Now it seems our comments & prayers for her safety behind the wheel were not in vain. I now KNOW for a fact JESUS has to be her co-pilot.
I can't get over how tough she is on vehicles as we get older the way she drives them. She has to be protected from above to not have a glove box full of tickets or bunch of fender benders. OMG. If there is a rule to the road.... like dont cross this line or these merge lanes starts here or use the passing lane for passing ONLY!! etc.... she will do the exact opposite almost as if to show she is going to do what she wants. At least she does respect red lights and stop signs. Gotta say though I just about have whiplash from all of those jack rabbit take offs and brake slams plus jumps over speed bumps etc... I know I just need to keep comments on her driving to myself and be thankful I am blessed to have her to do all she does to take care of me while working a full time job. Have a couple elderly friends with health issues who are either divorced or simply have no family living close enough to help them (when I cant) so I realize just how lucky I am. I know and bet both men and women on here can tell some very similar stories about their spouses driving etc...

True story. This morning my wife and I were walking through the parking lot of our gym and I commented on a nice looking Audi wagon. My wife replied why would anyone want a station wagon when you can have a SUV and run over stuff.

 

[ripcord]

Was your CR-V part of any of the recalls for fuel dilution? Has it had any repairs done by Honda? There might be something that Honda can do for you. https://www.nhtsa.gov/recalls

If it was mine, I might consider doing a oil change during the middle of winter just to get some of that fuel out of the crank case. What does >5% mean? It could be 10% for all we know based on that report.