Which Oil to use for E85

[Josh Sharpe]

We are trying to figure out which oil to use with our turbocharged GSX-R 600. We are using E85 and have noticed a few issues with it. The main issue brought to our attention is that there is a gooey substance building up on the inside wall of the intake of our motor. It is only building up where the injectors spray into our motor. Since some oil is being passed through our intake we believe so far that is created by the E85 being sprayed over the oil dripping in and a chemical reaction due to the heat of the motor. Has anyone else had and issue with this? It was also found to be a build up on the tips of our injectors. We know it is not our fuel system so it has to do with the oil, E85 and heat.

Also which general type of oil have teams that are using E85 switched to? We are researching synthetic oil that is better for E85 applications.

-Josh Sharpe
fsae.spsu.edu

[Josh Sharpe]

We are trying to figure out which oil to use with our turbocharged GSX-R 600. We are using E85 and have noticed a few issues with it. The main issue brought to our attention is that there is a gooey substance building up on the inside wall of the intake of our motor. It is only building up where the injectors spray into our motor. Since some oil is being passed through our intake we believe so far that is created by the E85 being sprayed over the oil dripping in and a chemical reaction due to the heat of the motor. Has anyone else had and issue with this? It was also found to be a build up on the tips of our injectors. We know it is not our fuel system so it has to do with the oil, E85 and heat.

Also which general type of oil have teams that are using E85 switched to? We are researching synthetic oil that is better for E85 applications.

-Josh Sharpe
fsae.spsu.edu

[Joe the plumber]

I don't understand the part about oil being passed through the intake?

[moose]

well.. from what I can understand you have at least 1 problem:

It consists of either E85 gumming up your intake near the injectors (I have no idea how to solve that)
and/or your Turbo seals are leaking, and oil is getting pulled through the intake (seen this before)
so, in terms of the turbo - there are lots of posts on solving that on the forum..and for the E85, before you blame that - you might want to rule out the turbo. However, if I had to guess, I'd say that the combo of E85+Oil+Heat isn't your problem, its only 2/3, or something else entirely (epoxy that can't take the heat, or something of the sort)

[Poe]

we always used plain old Castrol GTX 10W40 in our F4i (turbo E85). We did have the sticky residue build up on the intake runners as well.

[Josh Sharpe]

Yah we have the same sticky stuff in part of our intake runners as well as on the inside wall of the motor. The substance was also on the tips of our injectors which we had noticed on both our car and engine dyno. We recently had them cleaned and some test run on them.

Were you able to solve this issue Poe?

We have tried restricting the feed line to the turbo to limit the pressure of the oil going to it. According to the FSAE distributors of the GT12, they should only see between 10-28psi of oil pressure. The pressure coming off the crank case is 40psi and we have a .040" restrictor in the line and it still flows a lot of oil.

We have tested our fuel lines and they proved to withstand the E85. We also used a hot plate and heated up some E85 and oil mixed and we were able to recreate the substance. We are using regular motorcycle 10W-40 wet clutch safe oil. I was just wanting to see if anyone else has experience this issue and if the found a way to fix it. We are thinking of switching to full synthetic oil and see if that will help.

Just let me know if anyone else has experienced similar issues and if they found a way to overcome it.

[Poe]

The tips of our injectors were out of the flow stream, so we never noticed any build up on the tips. We never really worried about the sticky layer on the runners since it never got to be more than just a thin film. We just left it alone.