lgrant

99 XJ, 4.0L
I did the injector upgrade today (even though I know the results are generally negligible). Couldn't find my vasoline so ended up using some black moly grease out of the gun to ease the injectors into the rail and then into the manifold. Anybody know if that stuff is harmful to the O-rings? If it's okay for rubber boots (tie rod ends, etc) then maybe not that bad?

Thanks in advance for the help.
Larry

dave1123

I'm thinking I wouldn't want the moly additives going thru the injector nozzles from the rail side, but that's me. I just wiped mine with tranny fluid. They slid right in. You'll probably be all right.

DFlintstone

Any petroleum base is harmful to any rubber. (BTW that also means no mineral oil under the sheets if you want that rubber to hold). I'm pretty sure any O ring sold for injectors is viton, or nylon or something. Thinking that you will be OK there.

97grand4.0

Going from memory only, which admittedly has failed me before, I think the fsm says something like, 'coat the O rings with oil and install".
Having just completed a valve job and intake cleaning, I can tell you there is far more muck in your intake system than to worry about what might come from oil on the injector seals.
here tis': INSTALLATION 1. APPLY A SMALL AMOUNT OF ENGINE OIL TO EACH FUEL INJECTOR O RING. THIS WILL HELP IN FUEL RAIL INSTALLATION.

lgrant

Thanks for the replies. I'll leave as is and keep an eye out for leaks.
Larry

DFlintstone

The inner O rings leaking vacuum (IN) is the only place I've had trouble. Was from a botched installation.