3FE fuel injectors leaking. (1 Viewer)

Joined
Apr 29, 2004
Messages
175
Location
Pocatello, Idaho
My 92 died yesterday (see other post) and while diagnosing the problem I noticed one of the fuel injectors is leaking. I replaced all the seals etc...while the injectos were out being cleaned. Apparantly I did not get all of them in perfectly. Any tricks to reinstalling the injectors?

My Mitsu is a bugger getting the o-rings to seal. Only trick I've found is to soak them for 5 minutes in brake fluid before installation. The FSM said not to lube them with anything but a bit of gasoline so that is what I did. Any suggestion when I put new o-rings on tommorrow?
 
Joined
Aug 9, 2003
Messages
9,014
 
 
 
If the fuel rail holds all 6 and has those 3 attaching bolts/black insulators like the FZJ here's a tip for those O rings. Place a wood plank across the fenders or from one fender to the valve cover or lift eye so you can see what you're doing.

Place a drop of fuel on each rubber mounting ring just before installing the fuel rail. Loosely install the fuel rail with injectors by barely threading the three mounting bolts with black plastic insulators. Don't push the injectors down in yet - just knockin' at the door. Have a small bright flashlight with you up on the plank. With the flashlight, ensure all injectors are centered on their rubber mounting rings. Now, while you're pressing the fuel rail down to seat the injectors, roll it in a circle so the injectors look like they're all dancing in a row. This motion will help ensure that an injector doesn't hang up and will self center on the way in. With your other hand, give each injector a little push one at a time if they're stubborn, otherwise they'll all gently plop into place. When you think you have them in, stop and check each one very carefully with the flashlight to be sure before tightening the 3 bolts.

The bad news is you'll need to replace the one rubber mounting ring that's leaking because you put a permanent dent in it by screwing down the fuel rail with it cockeyed. If I were in dire straights (out on a trail and this happened), I'd at least pull it out and flip it over so the dent is against the intake man where it's got a better chance of sealing, but.... this is gasoline we're talking about and I believe the fuel rail is above the exhaust man on your engine?? Yikes.

Also, when going in to loosen things, you can often avoid removing the #1 fuel pipe from the filter just by loosening it up to get enough wiggle room to do this. Removing it completely can make it a real pain to reinsert the bolt and connect again.

DougM
 
Joined
Apr 29, 2004
Messages
175
Location
Pocatello, Idaho
The rail does have three posts as I recall and the rubber( mine are hard now) pieces that go under the studs to support the rail.

I'm not visualizing the pivot motion you are talking about though. The rail can't pivot so I'm assuming you mean the injectors although from your post you made it sound like they would all move in one motion. I'll have the intake off this afternoon. Maybe I'll snap some pictures while I'm in there. The turbo really gets in the way.
 
Joined
Aug 9, 2003
Messages
9,014
 
 
 
On the FZJ, the three black plastic "tubes" (better descriptor) that go under the studs to support the rail are hard black plastic. I am sure yours are too, rubber would never be used here so yours did not harden - they were designed hard. We're on the same page there.

As for the 'pivot' you're wondering about. When everything is loosely assembled as possible, you can grab the fuel rail and wiggle it up and down, or side to side, or what I'm talking about - up/to left/down/to right in what you'll realize is a circular motion. This will cause the injectors (which are loosely held to the fuel rail) to look like a line dance where the feet are stuck in the rubber mounting rings in the intake manifold and the heads (where the injectors attach to the fuel rail) are going around in circles. This action will cause the injector tips to work their way into the rubber mounting rings evenly if pressure is applied to push them in. It nicely self centers them as they keep moving around as they go in, which prevent them from grabbing on one side and deforming the rubber mounting ring as you did last time.

I don't know how to make this any clearer, so hopefully this will get it for you. When you say the fuel rail "cannot pivot" I think you'll find when it's loose you'll be able to work this motion out. HTH.

DougM
 
Joined
Apr 29, 2004
Messages
175
Location
Pocatello, Idaho
Ahhh.. yes I understand much better. I was able to find enough o-rings around town to put it together just debating on whether I want to head outside. It's getting coooold.
 
Joined
Apr 16, 2005
Messages
1,080
Location
TEXAS !!!
 
 
 
I used a little Vaseline on my o-rings upon re-installing them after being at the injection shop. Same procedure as on my 5-series when I put those injectors back in. The Bimmer indy recommeded the "vaz", and it has worked perfectly both times

Best of luck.

R.
 
Joined
Aug 9, 2003
Messages
9,014
 
 
 
Yeah, cold here too - 18 at the moment and we just got in from a get together and exercised the ABS a dozen times despite the winter tires. Getting fun.

Robert - these materials may be able to handle it, but Vaseline will attack rubber compounds. Might not be an issue, but worth pointing it out. I keep a bit of "personal lube" around for things like that. In this case, however, Toyota specifically states use nothing but a bit of gasoline. Dunno why. But leaking gasoline is a spector I'd rather not tempt. It seems to lube the rings even though by the time you start putting them in the gasoline has dried off.

DougM
 
Joined
Apr 16, 2005
Messages
1,080
Location
TEXAS !!!
 
 
 
Doug,

I had the same concern, but the response I was given when I asked the question of the "old wrench" was that the vaz is patroleum based and is compatible with all these o-rings. No issues so far. I have about 25k miles and 2.75 years on the 5-series fuel injector o-rings and about 2 years and 26k miles on the FZJ's.

I also used it on o-rings on the cooling system of the 5-series at the same time.

I figured that tech had done this on a lot of cars far more expensive than mine, and for a lot of years and had no issues, so I went for it.

I have also seen an A&P use vaz on o-rings when assembling landing gear systems on airplanes. That's another one I would think would be a big concern. Was told that he'd done it for years without a single issue. Go figure.

YMMV, just thought I'd throw it out there.
 

Users Who Are Viewing This Thread (Users: 0, Guests: 1)

Top Bottom