Brand New leaking injectors
Thread Starter
Le Mans Master
Joined: Jul 2004
Posts: 6,228
Likes: 698
From: Clifton Park, NY ............Clearwater, FL ... 85 Original Owner
Brand New leaking injectors
Someone just emailed me about the injectors that I bought from Five O. Asked if I had any problems with leaks. I did not, but they do. He said when installed, he had fuel pouring onto the intake. I suggested that if the mechanic was sure that the physical size of the injectors was correct that maybe he didn't get all the old o rings out. This is on a 91 L98. Any ideas would be helpfull, thanks.
Safety Car
Joined: May 2003
Posts: 3,789
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From: [Quote=WOEII] Is dried brown doodie powders man! [/Quote]
Hey neighboor 
I was told you should always use new o-rings, which I assume came with the injectors. The mechanic should already know to make sure the rails and the bungs are squeeky clean, and to lightly lube the o-rings with motor oil before installing the injector. My injectors did leak on installation and the cause was not enough lubricant on the o-rings. If the o-ring hits a dry spot when you're installing it, and you continue to push it in, part of the o-ring could get "stuck" if you will and roll away enough to cause a leak. Any sort of debris trapped behind the o-ring will also cause a leak. I ended up lubing the rails, bungs, and o-rings before I finally got it to not leak. This is with an aftermarket intake and rails but the rules should still apply. Make sure none of the o-rings are cracked. Sometimes it's hard to see and easy to overlook.
I was told you should always use new o-rings, which I assume came with the injectors. The mechanic should already know to make sure the rails and the bungs are squeeky clean, and to lightly lube the o-rings with motor oil before installing the injector. My injectors did leak on installation and the cause was not enough lubricant on the o-rings. If the o-ring hits a dry spot when you're installing it, and you continue to push it in, part of the o-ring could get "stuck" if you will and roll away enough to cause a leak. Any sort of debris trapped behind the o-ring will also cause a leak. I ended up lubing the rails, bungs, and o-rings before I finally got it to not leak. This is with an aftermarket intake and rails but the rules should still apply. Make sure none of the o-rings are cracked. Sometimes it's hard to see and easy to overlook.
