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leaky injectors

Posted: Mon Mar 10, 2008 3:00 pm
by 007zhr
Hi Guys...

drove the car the other day home and smelt lots of petrol after parking...
anyways, turns out that there is petrol around number 3 and 4 injectors...
when I pulled out the electirc connection on number 4, I saw its a bit wet in there as well..

whats the procedure guys, does it just need the o-rings to be replaced, or are tehy stuffed... and where's the best place to get the o-rings from ?

Thanks.

Posted: Mon Mar 10, 2008 3:54 pm
by Charlvdw
I bought new o-rings from nissan for R580+-. And still they are leaking so i think my one injector is moertoe.

Posted: Mon Mar 10, 2008 4:02 pm
by Hotstuff
@Charl - As I said to u over the weekend, it could be that your car had larger injectors and that your intake could've been machined????

@Mo - Buy the ones from Nissan as Charl said. I did it and as you saw on Sat, my car is a dry as the Namibian Desert...

R600 is a small price to pay and also waaaaaay less than a burnt out SX on the side of the road...

Posted: Mon Mar 10, 2008 6:40 pm
by widowmaker
mmm leaky injectors on an SX... now i've heard it all!


get it sorted out, so you can post about what oil to use!
(and is a 76mm really better than a 63mm zorst?)

Posted: Mon Mar 10, 2008 9:35 pm
by veecee
the problem here is that when i bought the injector o-rings from nissan, they didnt come to 580-00.

that seems way too high.

you need 4 o-rings, to create a seal with the fuel rail.
then you need 4 rubber seals for the back of the injector (these push against the rail).
then you need 4 rubber seals for the front of the injector (the tip). these push against the intake manifold.

thats 12 in total.

580/12= 48.33 each on average.

50 bucks for a little piece of rubber is way too much. they cant be that expensive!

and DO NOT forget to use a little red rubber grease. the castrol one is by far the best i've found!

then ask nat if your injectors leak if they are not broken and are installed properly??? :wink:

Posted: Tue Mar 11, 2008 6:36 am
by Toby
I bought 4 o-rings for the injectors from Nissan for something like R26. Yes R26. This is the o-ring at the top of the injector that goes into the fuel rail. The other rubbers were ok and they don't seal against the fuel pressure anyways.

Once you replace the o-ring and have cleaned and dried the injectors, take the car for a short drive and then check again. If it's looking even slightly wet around the connector, then it's very likely your old injector has seen it's days. This indicates that it's leaking from the body of the injector where the metal meets the plastic. Then it's time for new injectors.

Of course, in my case, I also had a scratched fuel rail which kept leaking, but thanks to ChemCool, I got a new fuel rail :)

Posted: Tue Mar 11, 2008 7:36 am
by 007zhr
thanks guys...

ok, so this is the process I'm going to try...
Get those rings that Toby is talking of first and see what it does...

I suppose it would be better to replace them all at once, but for now, lemme just get 2 of those and see what happens... hopefully it gets sorted, and is leaking from there...

so next question :) do I just need to remove the idling valve thing to get the fuel rail off, or do I need to strip the intake manifold

Posted: Tue Mar 11, 2008 8:23 am
by Charlvdw
Its a bitch of a job but i didnt strip the manifold. I yust pulled the idling valve, the two brackets between the plenum and head, the breather pipes, i also had to take the Trottle body of to get to some clamps below it. Something like that.

Ps: Mats look great thanks havent treid them yet. Thanx

Posted: Tue Mar 11, 2008 8:38 am
by Draco
Just some advice from my side, if it seems sure that the o-ring is gone and you have a jap spec motor....just loosen the fuel rail...the bolts holding the fuel rail needs to be loosend to almost before its last thread, then you can take the injectors out without removing the fuel rail.....also the bolt holding the fuel inlet and return pipes on the other side of the plenum, take this bolt out totally.

To do this on my car takes me about 30-40 min, out and in.

It's a whole different story removing the rail totally.....and if someone wondered...the jap spec(8 port) and the euro(4 port) fuel rails don't fit each other....I found that out the hard way....

Posted: Tue Mar 11, 2008 8:53 am
by veecee
draco's right. you dont have to totally remove the fuel rail, but taking it out gives you the chance to inspect the holes that the injectors fit into. fuel can leak past the o-rings if there is even a slight scratch on the surface.

toby is partially right. the o-rings seal off hte fuel pressure. but the rear rubber spacer pushes (applies pressure) onto the injector. and the front rubber is a seal. it seals the big hole in the manifold that the injector goes into. if the other rubbers aren't lekka then you will have other problems.

if the rear rubber doesnt apply enough pressure then the fuel injector might be loose and you might leak fuel too.

if the front rubber seal isn't lekka then you will have a leaky manifold, and you car wont run nicely!

Posted: Tue Mar 11, 2008 2:23 pm
by Doctor G
What's wrong with normal o-rings that you buy in a pack of 100,000 for like R50?

I don't see a reason to go OEM on O-rings?

Posted: Tue Mar 11, 2008 3:45 pm
by Draco
I have been using the normal o rings you buy from midas or screw man, it seems to work but I am still sceptic of the form of these o rings, ours are actually squer where these are round, I am also sceptic if it is able to handle the heat and the petrol factors it is subjected too.

As I said, I am using it and so far so good....but I remaIN SCEPTIC

Posted: Wed Mar 12, 2008 7:34 am
by Hotstuff
Doctor G wrote:What's wrong with normal o-rings that you buy in a pack of 100,000 for like R50?

I don't see a reason to go OEM on O-rings?
Some of these rings are not completely round. There are flat ones with square raised edges as Draco said.

This is what the seals / O-rings look like... Use these part numbers, they work perfectly on my car

Image
Image

The total cost of all these items...

Image

Posted: Wed Mar 12, 2008 9:10 am
by veecee
there you have it folks.

and hotstuffs engine is as dry as a bone around the fuel rail!

if yours isn't - go get a fire extinguisher FIRST!

Posted: Tue Mar 25, 2008 9:46 am
by Draco
For interest sake, I ordered o-rings from nissan, went to pick it up, it was the same round o-rings I purchased from midas and screw man, they charged me R37 per o-ring.....when I saw it was the round ones I gave it back and asked my money back, I told the salesman that I could perchase the same thing at midas for 60c a o-ring.....