piperRonnie said:
In defense of carnuck, the '86 Comanche probably didn't have too many components that were susceptible to the high alcohol content of E85.
But yes, today's vehicles have plastics everywhere.
In school: converted a Chevy Malibu and Silverado to E85. I miss those SAE days.
It's deceiving, because every O-ring, gasket, and seal from the fuel pump to the FPR (P-reg.) to the FPC (diagnostic P-conn.) to the fuel rail inlet tube conn. is potentially more susceptible to degradation. Of course, the standard E10 O-rings/seals will last awhile with E85, but if you use E85 fuel frequently, you're begging for it... The (current) GM engine design life used is commonly 150K miles, and elastomers that are OK for E10 don't make that if you run E85 fuel.
Here's a good paper to read on the subject:
http://www.engr.unl.edu/~ethanol/unl2000.pdf
(note the fuel pump failure on page 6...)
Also interesting, in parts of New England, many of the boat refueling stations recently started using E10, and there were numerous (unforeseen) issues with carburator problems (jets clogging) on pre-1994 engines due to deposits (fuel tank/line sediments, oxidation, etc...) being "loosened" by the E10 fuel. And that resulted with a switch from "E0" to only E10! Of course, the boat mechanics were very happy about that...
FYI - fuel system components used in countries that have lower fuel standards (like in South America) also have different design/material considerations, because the fuel there can be more corrosive. Usually that means more stainless steel internals.
Interesting e-mail thread. Keep it coming...