I have my Fitech running for two years now essentially trouble free. I did had some backfire issue when throttle is lifted after near full throttle acceleration. That was fixed with setpoint adjustment. Recently, the throttle body developed some fuel leaks. It started on the driver side and then the passenger side also. It turned out to be from the side pots that complete the fuel circuits that also hold down the injectors. It is secured by two screws each side. After opening them, I found the black rubber O-rings at the throttle body fuel feeds were essentially disintegrated. I suspected the material is not compatible with CA ethanol fuel. So I contacted Fitech even my warranty is out and they agreed to send me some replacement O rings. Will see what they send and if it is the same stuff that they used in the original. I google this and it appears Viton is probably the best material to use to deal with ethanol fuel. But how can you tell what is what?
Anyone else runs into this type of problem? I suppose this is not just EFI but can be a problem with gaskets, polymers in carbs.
Maybe give these guys a shout.
https://www.allorings.com/viton-o-rings
Relying on color isn't very reliable since all O-ring materials can be had in almost all colors, but brown is generally Viton. There are exceptions to this and every color though. Black can be darn near anything unfortunately.
The Viton O-ring's I've handled are generally stiffer and less rubbery feeling than your typical black generic rubber O-rings.
:iagree:
I've used many viton o'rings in the mold making industry and they were always brown. I agree though you can't always be sure based on colour.
Yes, general standard is Viton will be brown.
Going by "feel" Viton will generally be slicker to the touch than rubber/epdm.
Yes, fuel in CA. is the root of all evil to all our classics.
The o-rings for their injectors should be standard for many.
When in doubt, you can order some you know are Viton.