Injectors - How To Remove/replace/upgrade

[Psymon]

I wish i read this 2 weeks ago before i pulled off my plenum.

[PHaT MR30]

Do you have to remove the injectors to replace the pintle caps?

And does anyone know the part number for new pintle caps?

I have been scouring FAST but it doesn't seem to list them

[WhiteHot_R33]

Hey man, great guide. . .

Im going to attempt this on the weekend, nismo 555cc's into RB25.

so you didn't have to replace any parts apart from the injectors? just re-used the old o-rings?

i want to make sure i dont need any other bits before i pull it apart!

cheers!

[MearCat]

Thanks No parts need to be replaced, unless you break simething or lose the small black plastic spacer rings (easy to drop when taking the rail out and hard to find late).

I used a small amount of generic grease to coat the o-rings before putting them back in but not 100% sure whether that's even necessary.

[WhiteHot_R33]

Just an update on todays work. . . thanks to all those who offered advice.

Everything went pretty well, I used vice grips to loosen the injector cap screws. Then with the help of a mate, we inserted a screwdriver into the hole in each side of the injectors and levered them out over the shaft of another screwdriver, across the screw tabs. (four screwdivers) if that make sense.

we re-used the o-rings, there's two on each injector, one top and bottom.

once it was all back together i punched in some correction and fired it up. . .

my concern is the idle is very rough. like its on 5 cylinders. it definately goes ok on boost and driving around. just idles like poo

any suggestions?

cheers

[Leadfoot]

Just an update on todays work. . . thanks to all those who offered advice.

Everything went pretty well, I used vice grips to loosen the injector cap screws. Then with the help of a mate, we inserted a screwdriver into the hole in each side of the injectors and levered them out over the shaft of another screwdriver, across the screw tabs. (four screwdivers) if that make sense.

we re-used the o-rings, there's two on each injector, one top and bottom.

once it was all back together i punched in some correction and fired it up. . .

my concern is the idle is very rough. like its on 5 cylinders. it definately goes ok on boost and driving around. just idles like poo

any suggestions?

cheers

latency is most likely incorrect

you will need a full tune to correct this out

To make removal of the injectors easier I would highly recommend using a short section of brass tubing to push the injector out from underneath rather than trying to pul/pry out from the top with a screwdriver/s. My o-rings must have been very dry or something and there was no physical way they would come out from the top. If you look closel from underneath the injector you will note that there is a very fine gap between the pintle outer shaft and the hole in the injector rail. Brass tube will fit in this gap and the injector can then be pushed directly out. If they are tight this is the only way they will come out without being damaged.

Yeah, I used multigrips on the injector cap screws as well. They seemed to be "superglued" as well.

[WhiteHot_R33]

Cheers man, i used .18 for the latency correction, believe it is .71 - .528? got the .71 from google and the .528 from pauls's PFC FAQ. . .

feel free to enlighten me if Im wrong

[Sheng]

looks interesting

will be doing it on my 34 soon

hope it wouldnt be much of a challenge

[Leadfoot]

Cheers man, i used .18 for the latency correction, believe it is .71 - .528? got the .71 from google and the .528 from pauls's PFC FAQ. . .

feel free to enlighten me if Im wrong

Also installed Nismo 555's. Forum advice said use 0.71ms latency however it idled so rich it wasnt funny and I only just limped to the tuner.

Would not come onto boost at all although the bigger turbo would have been 90% of the reason for that.

My advice, if your idle sounds reasonable on 0.528ms then leave it there until you can do a dyno run.

Boosting it before a dyno tune is not advisable. Every injector and motor setup is different.

Latency and injector correction factors can only do so much and assume everything else is perfect.

[PHaT MR30]

A bit of advice for anyone out there doing this.

I made a tool to remove the injectors myself, a pair of pointy nose pliers from bunnings, heated the ends up and bent them facing towards each other. Worked a treat, but its still a task getting them out.

o-rings are majorly important to check and replace, a hairline can cause disasters later (discussed below).

Fitted some 555 Nismo's to a mates car (well he did), fired the engine and the thing only ran on 5 cylinders, a few tests later and nearly hydraulic lock his engine!

Turned out the small o-ring on number 2 injector had a tiny crack in it and fuel was gushing out from there!

Put a new o-ring on and fired it up and she was fine.

[Syphon]

A bit of advice for anyone out there doing this.

I made a tool to remove the injectors myself, a pair of pointy nose pliers from bunnings, heated the ends up and bent them facing towards each other. Worked a treat, but its still a task getting them out.

o-rings are majorly important to check and replace, a hairline can cause disasters later (discussed below).

Fitted some 555 Nismo's to a mates car (well he did), fired the engine and the thing only ran on 5 cylinders, a few tests later and nearly hydraulic lock his engine!

Turned out the small o-ring on number 2 injector had a tiny crack in it and fuel was gushing out from there!

Put a new o-ring on and fired it up and she was fine.

Interesting you say that, I did mine recently aswell and almost hydraulic locked the motor. Pissing past cyl 6 O-Ring. What happens is the orings bind when the injector is being pushed back in, usually because they are dry, so something like grease, or vaseline is VERY IMPORTANT. I ended up just replacing all the injector orings, they aren't expensive

Also worth pulling the coilpacks and plugs out, leave the injectors unplugged for good measure, unplug the crank angle sensor and crank the motor over and check for leakage into cylinders. Also worth grounding the fuel pump, let it run for a say 2 minutes to prime the system, then crank it over with no spark plugs in, and again check for leakage. You can also crimp the return line if your anal, which will basically max the pressure, I wouldn't suggest running at max pressure for much for than 30 seconds though.

If it doesn't leak then, your good to go.

A previous post about sounding like 5 cylinders, sounds identical to my issue, i just knew it was down a cylinder, so shut it down and traced the problem. Can't say I would want to run up a motor on the dyno with a massive leaking injector. BTW, did I mention I hate side-feed injectors?

[datto260Z]

Good write up bud. Wish I had seen it before I satrted, but it saved me in the end.

Ill add a bit for this. Im installing Sard 550cc injectors atm, for anyone who is confused on how to get the collars on properly, you need to remove the upper O-ring, slide the collar all the way up, then replace the Sard O-ring with the original (preferably new one) so as it seals the bucket at the top. You will also need to remove the rubber piece that is inside the "hat" so as it will bolt all the way down. Also, make sure you lube the seals with Vasoline, do not use oil as the seals will degrade from it. You will know if you pinch a seal from no lube, it will piss fuel all over the place.

Also I had to use a impact wrench to get mine out, it was a last resort and even then, it was still rounding the screws to a degree, so for anyone having trouble doing it, prepare to get some replacements. Sard supply replacement hex items which are so much easier.

Edited November 12, 2007 by datto260Z

[benl1981]

Nice tutorial! Interesting my R33 series 1 had 5 bolts holding the rail in not 3 as pictured for your Series 2

Also, do most people just replace o-rings and leave the insulators alone? Im going to check all mine and see that they look ok.

Good idea to replace all the hoses around there. Disturbing 10year+ old hoses isn't a good thing.

Anyone know a good place in sydney that does cleaning and flow testing for $25 or less an injector?

Cheers

Edited November 19, 2007 by benl1981

[sam5709]

yeh this thread also saved me $, did it all myself and was pretty straight forward

[stolen_s15]

Good write up mate, I'll give it a crack this weekend.

[almzro3e]

great job man

i really thank you so much and i will do it

when i recive my new injectores

[Pal]

just a bit of info for putting grease on o rings, only use rubber grease as some industrial greases will eat rubber and that can lead to disaster.

U HAVE BEEN WARNED!!!!

[MearCat]

just a bit of info for putting grease on o rings, only use rubber grease as some industrial greases will eat rubber and that can lead to disaster.

U HAVE BEEN WARNED!!!!

Cheers - I will update the tutorial with that

[Pal]

No Problems, nice quick update

[engo]

also with those o-rings.. instead of grease just buy some silicon spray for $10... spray the o-rings.. put em one and then spray the injectors and slot her in... tooooooooooo easi...