Injector pintle cap problem

[skiddusmarkus]

I have some 700cc injectors to go in as the car is being mapped soon but when test fitting them and tightening down the fuel rail this happened.

Its my own fault for not putting a drop of oil on 1st to ease it in and the pintle cap creased.I bought a service kit off ebay but the caps in that are ffractionally smaller inside so they won't go over the end of the injector.

Its only done it on 1 of them so the others are ok.My thoughts are I could(in order of sensibility):

1.Buy the right cap from Nissan but risk it not arriving in time.
2.Get the new cap machined slightly to make it a few thou' larger.
3.Trim the creasing off the cap and use it anyway.
4.Remove the cap altogether.

Anyone got any other ideas or had a simialr situation themselves?

 

[skiddusmarkus]

Or does anyone have a spare they don't need?

 

[stevepudney]

Opp's ...........

It looks like the sealing part of the damaged cap is still in tact though, so as a stop gap until you find a proper replacement I'd be tempted to see if you can't straighten out the existing cap. I'd remove the cap and see if boiling water warms the plastic enough to pull the cap back into shape, failing that leave the cap on the injector and gently warm it with a hot air/paint stripper gun or even a hair dryer and try and smooth it out a little. Failing that I would see by if warming up the "slightly to small" cap it might soften it enough so you could stretch it on to the end of the injector. Failing that I'd ask Bob if he has a spare one from a fucked injector, failing that I'd go to a scrappy and source a cap that fitted.
warming the plastic

 

[skiddusmarkus]

I tried putting the new cap in boiling water last night Steve and it wasn't having any of it.Ill try messing about with the knackered cap and see how it goes, the problem is you can't really use any pliers or anything on it due to the shape and it could just ,make it even worse.

 

[skiddusmarkus]

Ok, I put the injector in the freezer to shrink the metal and put the cap in boiling water to soften it up a bit and managed to get a new cap on but it doesn't look quite right to me.

The metal prong on the end of the injector is slightly more recessed with the new cap and I am guessing this will affect the spray pattern?This is because the new cap is very slightly longer than the original one.I could cut 0.5mm off another new cap(I have 4 altogether) but its pretty tough plastic and I don't have any special cutting tools othe rthan knives.

Thoughts?

 

[stevepudney]

The seal is made by the rubber O ring sitting tight up against the shoulder on the injector body so as long as the O ring still fits snug on the cap you should still get a seal. As far as removing some off the length of the cap goes, just use sand paper to remove a little material.

 

[red reading]

to cut it down go and buy a brand new stanley knife,or go to a model shop and buy a scalple.

 

[stevepudney]

to cut it down go and buy a brand new stanley knife,or go to a model shop and buy a scalple.

you'll squish the plastic with a blade and you wont get an accurate cut, just use fine sandpaper

 

[red reading]

you'll squish the plastic with a blade and you wont get an accurate cut, just use fine sandpaper

only if you are stupid! put something inside it first to stop it being squished

 

[stevepudney]

What a stupid thing to say, he owns a Pulsar for christs sake..........

 

[red reading]

What a stupid thing to say, he owns a Pulsar for christs sake..........

lol.....

 

[PobodY]

only if you are stupid! put something inside it first to stop it being squished

Something about the same size as an injector... that give me an idea. :-D:shock::doh:

 

[red reading]

Something about the same size as an injector... that give me an idea. :-D:shock::doh:

Don't go putting your cock in there george!

 

[skiddusmarkus]

Sorted this now, got some new caps(bought 6 so can swap all 4 so no different spray patterns and 2 spares) from a local guy(AF Tuning)in Chesterfield.He had to order them in specially and they were £1 each, might help someone in the future.