Effects of E85 on fuel injector solenoids

[ashter]

I have recently done an E85 conversion on my Turbo Eclipse. This fuel is the best thing since sliced bread for high powered 4 bangers that are otherwise restricted on "premium" grade gasoline AKI ratings. One concern that I have is the long-term effects on the injectors. I sent an e-mail to RC engineering and they do not reccomend using E85 on their injectors, but if I must, they reccomend service every 3 months. I find that kind of excessive, but I'm by no means an authority on the subject.

Ethanol is a corrosive substance so I hear, but what corrosion would the injectors experience? Would this cause the pintle seats erode? The only differences I've found on Google between gasoline injecotrs and E85 is that the ethanol ones lean more on the ball type, whereas the gasoline typically uses the pintle. I can't verify any credibility on the source of that information, either.

The winter blend which is being served in my area is category 3 (70% Ethanol) at the moment for the record

 

[WGJ]

Since OE manufacturers have to put a lot of effort into qualifying the whole fuel system (filler-tank-engine)for E85 use, I should have thought that E70 would need similar precautions.
Assuming that your injectors are made from stainless steels, it's the 'O' rings that will suffer from alcohols.
If your injectors contain anything other that stainless grades, then the potential for E70 to contain dissolved water will risk rust corrosion.

Bill

 

[Warmington]

The main damage would be loss of sealing and bad spray at the injector tips, possibly sticking issues as well.

Yes i agree its a common misconception that the ethanol chemical itself will deteriorate the metal parts of the injector, but rather that as methanol is hydrophillic its the water in the molecule that rusts components. I have heard that race teams using 100% methanol also must purge the fuel system each time it has been run.

Flex fuel vehicles now have entire fuel systems that can tolerate up to 96 odd % ethanol without damage due to different (synthetic)seals and non-ferrous metals in the injectors/pumps.

 

[dgallup]

I don't know exactly which injectors you have since RC resells many brands with different internal construction/materials. However, we have run some for 600 million cycles on E85 with no ill effects. Some early Delphi Multec injectors had a short life on ethanol.

 

[patprimmer]

Standing in ethanol might do more damage to some components than continuous running as it might allow more time to absorb water. Continuous running ensures a continuing supply of relatively fresh fuel.

Regards

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[dgallup]

We have some sitting in bottles of sour fuel mixtures too. And thermal cycle, etc. However, you have to talk specific injector designs because there significant differences between them.