Fuel Dilution - Effect on engine seals

[Overfill]

What are some of the effects gasoline might have on rubber seals over time via fuel dilution of motor oil?

Qlthough not the object of discussion, this thread is instigated by the still present condition of gas direct injected motors' propensity to seep fuel into the oil.

Important seals of concern are rear main seal, valve stem seals, oil pan gasket, and valve cover gasket.

Will the mix dry it out, make it swell, ect..?

 

[Triple_Se7en]

Will probably have insignificant effects, should the owner stay on the viscosity thick-end of their owners manuals and change the oil more often (severe duty), versus the school of the past decade, which dictates things like obeying oil monitors on the dash, or hypothetical 10 OCIs.

 

[anndel]

I believe you'll have follow stricter OCIs versus non-GDI engines. I know I would follow the mfr's OCI schedule to the T.

 

[wemay]

To anndel's post...

Our vehicles are not only GDI and T-GDI but we drive under the severe service maintenance schedules found in our Owner's Manual. Our commute is in bumper to bumper rush hour traffic to our destinations that are roughly a 10 mile round trip for the turbo and a 7 mile round trip for the normally aspirated Sportage. It also gets very hot and humid here. Maybe not Phoenix heat, but hot none the less.

These are the severe service schedules from the Owner's Manuals:
3750 for the GDI
3000 for the T-GDI

 

[JAG]

On the following link, filter on gasoline and see the compatibility chart. The next step is to identify what seal materials your engine uses that come in contact with the motor oil. https://www.marcorubber.com/o-ring-chemical-compatibility-chart.htm

The gasoline in the oil in many GDI engines will keep coming back pretty quickly when you change the oil, so changing it more frequently doesn't have anywhere near the positive effect on fuel ditluion as it does on percent of active oil additives remaining. If you can decrease the fuel dilution by a method like using higher octane fuel, or keeping the oil hotter by manually keeping it in a lower gear than the auto. transmission would keep it or by oil pan or block heater or covering part of the grill.

 

[parshisa]

Siphoned 0.2qts of excess oil (fuel dilution again) and with 1,600mi on the oil my god was it black. I mean, nit pute black but same color as it was 6k on it. Not sure if that's amsoil formulation getting dark so fast, or honda TGDI killing it so fast...

 

[StevieC]

Originally Posted by parshisa
Siphoned 0.2qts of excess oil (fuel dilution again) and with 1,600mi on the oil my god was it black. I mean, nit pute black but same color as it was 6k on it. Not sure if that's amsoil formulation getting dark so fast, or honda TGDI killing it so fast...

Colour is not an indicator of oil life.

https://www.edmunds.com/car-maintenance/top-7-urban-legends-about-motor-oil.html

Quote
Check the oil on the dipstick. If it's black, change the oil. Experts say this is a myth, as is the related notion that you can identify spent oil by smell. "That is old school," says Kristen Huff, vice president of Blackstone Laboratories in Fort Wayne, Indiana. "Oil is meant to get dark — it means it's doing its job," she says. As GM's Matt Snider says in this video, different additives change the oil's color. The bottom line: Black oil still has plenty of life left in it.


The reason I quoted Edmunds who quotes Blackstone Labs is so that it's not me saying it, or me defending Amsoil. It's general knowledge (outside of the dumb typical car owner) that oil life can't be determined by colour. A UOA is the only way to properly tell. Not smell, not colour, not because your friend bob says to change it, not because of "Butt Dyno" telling you it's time.

 

[parshisa]

I didn't say that it is time to change the oil because it is black. I ran UOA and know very well what is capable of. It was an observation. That's all

 

[StevieC]

Originally Posted by parshisa
I didn't say that it is time to change the oil because it is black. I ran UOA and know very well what is capable of. It was an observation. That's all


Seemed otherwise, that's why I replied with the above.
Originally Posted by parshisa
... or honda TGDI killing it so fast...

 

[1JZ_E46]

It's amazing how fast some TGDI engines turn oil black. Might as wells be diesels with the amount of soot they produce. Our Mini is the same way.

 

[Bryanccfshr]

Originally Posted by 1JZ_E46
It's amazing how fast some TGDI engines turn oil black. Might as wells be diesels with the amount of soot they produce. Our Mini is the same way.


Yeah even regular old DS4 Toyota gdi can produce some graphite coatings on the unwetted portion of the dipstick. The oil does go black. That's why it only goes 5k.

 

[bbhero]

^^^^^^

Another really good post... I am glad you are on here. You add a lot.

 

[StevieC]

Originally Posted by Bryanccfshr
Originally Posted by 1JZ_E46
It's amazing how fast some TGDI engines turn oil black. Might as wells be diesels with the amount of soot they produce. Our Mini is the same way.


Yeah even regular old DS4 Toyota gdi can produce some graphite coatings on the unwetted portion of the dipstick. The oil does go black. That's why it only goes 5k.

My highlander had the D4-S in it (2GR-FKS 3.5 V6) and the manual said under normal driving conditions it could go 10K miles (16,000km) before an oil change. I ran it as high as 6K miles (10,000km) and the oil was still amber on the dipstick. I did this over 2 changes as I was keeping the OCI short during the break-in period and then ended up trading it because I hated the transmission in it.

Also soot in GDI is at the nano-scale so it would take a ton of it before it would be visual. Now that D.I. is harder on the oil darkening it quicker, maybe. But I don't think it's the soot you are "seeing" that is causing that darkening like it would in Diesel.

 

[JohnnyJohnson]

StevieC thanks for that last tad of info I had wonder why you got rid of it. I had consider the Highlander as a replacement for my Corolla but it just seems no one is really building better cars they are just BS their customers.

 

[OilUzer]

Originally Posted by parshisa
Siphoned 0.2qts of excess oil (fuel dilution again) and with 1,600mi on the oil my god was it black. I mean, nit pute black but same color as it was 6k on it. Not sure if that's amsoil formulation getting dark so fast, or honda TGDI killing it so fast...


I've seen the darkest oil ever only with our gdi ... At least 4 different brands including 2 good quality syn ... It has nothing to do with oil or amsoil it's the crappy gdi engine!

 

[OilUzer]

Originally Posted by StevieC
Originally Posted by Bryanccfshr
Originally Posted by 1JZ_E46
It's amazing how fast some TGDI engines turn oil black. Might as wells be diesels with the amount of soot they produce. Our Mini is the same way.


Yeah even regular old DS4 Toyota gdi can produce some graphite coatings on the unwetted portion of the dipstick. The oil does go black. That's why it only goes 5k.

My highlander had the D4-S in it (2GR-FKS 3.5 V6) and the manual said under normal driving conditions it could go 10K miles (16,000km) before an oil change. I ran it as high as 6K miles (10,000km) and the oil was still amber on the dipstick. I did this over 2 changes as I was keeping the OCI short during the break-in period and then ended up trading it because I hated the transmission in it.

Also soot in GDI is at the nano-scale so it would take a ton of it before it would be visual. Now that D.I. is harder on the oil darkening it quicker, maybe. But I don't think it's the soot you are "seeing" that is causing that darkening like it would in Diesel.


What do you think is causing the darkening in gdi engines so quickly?

 

[ChrisD46]

weemay: Quaker State Ultimate Durability 5W30 Synthetic oil would be excellent for your 2.4L non turbo ($19 every day price at WM) ... I would use that over any conventional or syn blend in a GDI engine - just fine for the turbo as well OR look for Pennzoil Platinum 5W30 synthetic at WM on roll back price and use for all your Kia / Hyundai GDI engines . Severe Service schedule and check your oil levels often to keep at the full mark .
Originally Posted by wemay
To anndel's post...

Our vehicles are not only GDI and T-GDI but we drive under the severe service maintenance schedules found in our Owner's Manual. Our commute is in bumper to bumper rush hour traffic to our destinations that are roughly a 10 mile round trip for the turbo and a 7 mile round trip for the normally aspirated Sportage. It also gets very hot and humid here. Maybe not Phoenix heat, but hot none the less.

These are the severe service schedules from the Owner's Manuals:
3750 for the GDI
3000 for the T-GDI

 

[Triple_Se7en]

Originally Posted by OilUzer
[

What do you think is causing the darkening in gdi engines so quickly?


My guess is Carbon

 

[wemay]

ChrisD46, some of the reason why i still use Conventional at times...

Although i don't worry to much about LSPI in a naturally aspirated GDi.

 

[StevieC]

Originally Posted by OilUzer
Originally Posted by StevieC
Originally Posted by Bryanccfshr
Originally Posted by 1JZ_E46
It's amazing how fast some TGDI engines turn oil black. Might as wells be diesels with the amount of soot they produce. Our Mini is the same way.


Yeah even regular old DS4 Toyota gdi can produce some graphite coatings on the unwetted portion of the dipstick. The oil does go black. That's why it only goes 5k.

My highlander had the D4-S in it (2GR-FKS 3.5 V6) and the manual said under normal driving conditions it could go 10K miles (16,000km) before an oil change. I ran it as high as 6K miles (10,000km) and the oil was still amber on the dipstick. I did this over 2 changes as I was keeping the OCI short during the break-in period and then ended up trading it because I hated the transmission in it.

Also soot in GDI is at the nano-scale so it would take a ton of it before it would be visual. Now that D.I. is harder on the oil darkening it quicker, maybe. But I don't think it's the soot you are "seeing" that is causing that darkening like it would in Diesel.


What do you think is causing the darkening in gdi engines so quickly?


I haven't noticed it darkening any quicker than a PFI engine with the exception of the TGDI's which I think is heat related from the turbo causing it to darken quicker. I think it's just how the oils additives are reacting to the conditions in the engine causing the darkening.