I guess I'm fascinated with the rotary engine in my "new to me" Rx-8 so I'm doing some research. I noticed in an article about possible airplane usage of the Mazda rotary engine that the author thought that : "Mazda used nylon, five cent tubes to feed oil to the apex lube injectors. These tubes are hidden and inaccessible under the intake manifold. After a few years these get old, get brittle and get cracked. Many if not most Mazda rotary engines in cars that have died after ten years and several hundred thousand miles have died for this ridiculous reason."
Has anyone heard of this before, and, if so, is there a fix? (or is there no need for a fix?)
Thanks!

 

These are the "tubes" that lead from the oil metering pump to the oil injectors. After many years they do get brittle and can break. I've seem them last 20+ years in use with no issues but the second you actually touch one or try to move one out of the way when working on the car and snap, they can break. There have been people that have made their own out of many things just by reusing the original tube ends. It isn't that hard to make new ones but it will be many years until anyone needs to worry about them. Chances are you'll either no longer have the car or will be replacing an engine by the time they need to be changed. You'd do it with an engine change anyways since they don't cost that much.

 

Even the old brittle ones won't break if you don't screw with them.

Don't worry about it unless you plan on removing the intake manifold in 20 years or so.

Mine on my 7 are replaced with clear teflon hardish tubing, it works great.