OK to use a little sealant on injectors?
 

Car's idling at 2200 when warm, starts whistling over 4 psi. Bought a new bottle of vacuum leak tester (which is labeled "carb cleaner" for some reason...) and it's the #4 injector. New seal kit being picked up tomorrow, but just to be paranoid...

...is it OK to use a little sealant? Like black silicone?

I wouldn't use silicone sealant just put a dab of oil on the oring so it pops into the fuel rail easier, and I found instead of using the plastic/rubber thing (mine were hard plastic because well they had 260k miles on them) that goes into the head that an 88 ford ranger Injector Oring on the end of the injector seals nice and good at the head. Much cheaper than the OEM part.

I wouldn't use any sealant. Just make sure everything is in place when you bolt the rail down. It's easy to get something cocked to one side or crushed when you tighten it down, so many little pieces to keep in place.

NO! Seriously

Some if not most silicones are petroleum based.. IE they disolve in gas! So no..

Well that's that answered then. Thanks :)

Looks like I'll just try to line things up well.

Don't forget the fuel injector spacers either. Also don't overtorque. Torque to specs (on m.net i think). Buy extras of all the little parts for when you drop them down your engine, in the grass etc.

sealant on the base where they fit into the IM? Don't act like I haven't used black rtv there....

Yes, on the base.

I just got back from the on-base auto shop (heated bays FTW...) and it looks like I've solved the vac leak just by pulling the injector and cleaning things well, and lining everything up properly.

this is what you should be using

Super Lube Synthetic Grease With PTFE Teflon 82340

Clean is the key, no grease or anything should be required. I actually think I have had a very small leak since my rebuild like a year ago, but I have been too lazy to mess with it. I smell fuel almost all the time under the hood, but see nothing really visible. The smallest chunk of grit under a seal or o-ring will mess up your good seal. The first time I did mine one of the injector to rail seals get twisted, and the second time I left a damn spacer out... :vash: Third time seemed to work so I left it alone. Nothing more frustrating than all of those damn seals and spacers moving around while you try to lower the rail and injectors in with only two hands to hold it all.

I used Eucerine Aquaphor and they slide right in a seal.

And then you used the rest on your anooos?:giggle:

There is a product just for this type of application. Fuel Lube. also used in carburetors, throttle bodies, gaskets and anywhere where else exposed to fuel needing to seal or move without being washed away by the fuels. O-rings will seal far better and come apart easily when needed.
EZ TURN LUBRICANT from Aircraft Spruce

Takes very little of this and use sparingly. Gobbed on the extra can block up a fuel system.

Once again folks, this is a vacuum leak, nothing to do with a fuel leak.

The vacuum leak has returned. Sigh. Going to try some grease (thanks for the recommendations duders) and if that doesn't solve it, I'll move on to crnrhrd's Ranger solution.