Best way to change pintle caps on injectors.

[2k3TitaniumSe]

Well I cracked a pintle cap pretty bad on my new injector. Now I was thinking of swapping the pintle caps with my old injector but don't see how it can be done. Any ways about doing this? And also for changing all six injectors, what do I need. What I can think of are the intake manifold gasket, o rings, and.....? Anything I'm missing to get the job done correctly? Thanks

[92 Max]

First of all does anyone know where to get new injector tip caps for these Bosch injectors?? I could use some also.
For the injector replacement, I bought new upper and lower "O" rings and the injector to manifold cushions (NAPA has a kit). Grease these with petroleum grease before installing (it's easy to cut or damage the "O" rings during assembly, then it'll leak, DON'T ask me why I know). Replace the plenum to manifold gasket, and the throttle butterfly housing gasket (if you take it off the plenum). You don't need any gasket sealant if you buy the OEM gaskets. They have some magic sealant on them (but do clean the old gaskets off the surface).
Extra- You could also replace the EGR gasket if you've a mind to. If they're old, replace all the fuel lines with the fuel INJECTION, high pressure fuel line (SAE 30R9), NOT low pressure non-injector fuel line. Also, if you're taking off the plenum replace the vacuum hose that goes from the rear valve cover to the gold vacuum pipe in front of the plenum ( these are hard to replace with things in place).

[aspirin240]

Originally Posted by 92 Max

First of all does anyone know where to get new injector tip caps for these Bosch injectors?? I could use some also.
For the injector replacement, I bought new upper and lower "O" rings and the injector to manifold cushions (NAPA has a kit). Grease these with petroleum grease before installing (it's easy to cut or damage the "O" rings during assembly, then it'll leak, DON'T ask me why I know). Replace the plenum to manifold gasket, and the throttle butterfly housing gasket (if you take it off the plenum). You don't need any gasket sealant if you buy the OEM gaskets. They have some magic sealant on them (but do clean the old gaskets off the surface).
Extra- You could also replace the EGR gasket if you've a mind to. If they're old, replace all the fuel lines with the fuel INJECTION, high pressure fuel line (SAE 30R9), NOT low pressure non-injector fuel line. Also, if you're taking off the plenum replace the vacuum hose that goes from the rear valve cover to the gold vacuum pipe in front of the plenum ( these are hard to replace with things in place).

Hi 92 Max

Do you know the diameter for the fuel line hose?

[Juicey]

Hey, I just replaced a fuel injector on my 93 Max (VG engine). I got some good advice from a thread I created:

http://forums.maxima.org/showthread.php?t=469791

There's a write up for the VE in the stickey's. The biggest problems I had were the hoses. Some get fused onto their metal connectors after being on there for so long. For some hoses you can just take them off and take them to Advanced or whatever place you go and they will match the diameter and give you a replacement. The Auto Zone I went to sells the stuff by the foot though so be prepared to get more than you want, which can be a good thing.

Also the hex nuts that hold the manifold on can be a REAL ***** to get off. Make sure you get some hex extensions for your rachet. They're not on there REAL hard, per only 25 INCH foot pounds, but a small allen wretch isn't going to get them off if you know what I mean.

When taking the manifold off I tried to remove as few parts as possible. That being said I have bought the intake manifold gasket kit ($40.00) and the throttle body gasket (advanced had it listed as carbuerator (SP)) and EGR gasket.

The intake manifold gasket kit (which is pretty much the only way the intake gaskets are sold, in a kit) contains THREE gaskets. The upper gasket and two lower gaskets, you don't have to worry about the second, metal, lower intake manifold gasket unless you are planning on taking off the entire lower intake manifold (lower intake is in two parts, you only need the upper part to replace injector).

So that being said I have a spare gasket. If you go into the lower, lower part of the manifold you'll have to drain your coolant as a coolant hose goes into the lower part of the lower manifold.

I had to use the end of a hammer to pry out the old injector. It was in there pretty good and putting pliers on the plastic to pull it out only caused the decade old plastic to shatter. I noticed there seems to be a couple holes near the upper part of the injector so it appears perhaps Nissan has some tool for getting the injectors out?

I haven't put everything back yet as I am waiting for the injector, which will come today.

Before you ask me what kind of fool would go into the manifold without a spare part consider this. My 1993 VG injectors, as I'm sure you know, come in green dot/mark or yellow/mark. I called my Nissan stealership and gave them my VIN. They didn't have a f*cking clue which one mine was. So I had to get in there to discover it was green dot/mark before I could order it.

I'll post here again with any problems I had putting everything back on. It's not real complicated and I felt hesitant doing something beyond replacing the fuel filter, air filter etc but it's not bad, just a lot of crap to take off and MANY hoses to pull. If you're not real strong make sure you have someone that is that can grip those hoses and pull them off.

[92 Max]

Originally Posted by aspirin240

Hi 92 Max

Do you know the diameter for the fuel line hose?

First of all, if your going to replace the fuel hose, make your life simpler and just cut them off. Try not to score the metal pipe underneath. Then take them in to size them, although I'm pretty sure it's 5/16" ID hose.
When refitting hoses, lube them before fitting ( gasoline or petroleum based oil) and be careful about the metal rails. The force to push on these hoses is just higher than the force to bend the rails ( again, don't ask how I know). You may want to support the rail fittings with wedges of wood or such, so that pushing on them won't bend them.

[Aaron92SE]

Originally Posted by 2k3TitaniumSe

Well I cracked a pintle cap pretty bad on my new injector. Now I was thinking of swapping the pintle caps with my old injector but don't see how it can be done. Any ways about doing this? And also for changing all six injectors, what do I need. What I can think of are the intake manifold gasket, o rings, and.....? Anything I'm missing to get the job done correctly? Thanks

The old pintle caps will always break if you push on them. So I had to replace mine for all 6. Some guys are able to get new pintle caps from local injector shops. I called around the ones in Las Vegas and nobody had anything to help me out.

So I called the guys at C&C Fuel Injection in Reno, NV. He was very nice on the phone. He told me to get him a few pictures of the injector pintle cap with exact measurements. Sure enough, he had then in stock. He shipped them to me for about $10-15. I didn't care what they cost. I was happy to get some! They worked great. Just padded the bench vise a little bit with shop towels and pressed them in with the new lower Oring. They didn't take much pressure to pop them in place.

[R92max]

I got them from this place: 1-866-577-FUEL

[Juicey]

Does anyone have a picture of a pintle cap?

[Greeny]

Originally Posted by Juicey

Does anyone have a picture of a pintle cap?

[92 Max]

Originally Posted by Aaron92SE

So I called the guys at C&C Fuel Injection in Reno, NV. He was very nice on the phone. He told me to get him a few pictures of the injector pintle cap with exact measurements. Sure enough, he had then in stock. He shipped them to me for about $10-15. I didn't care what they cost. I was happy to get some! They worked great. Just padded the bench vise a little bit with shop towels and pressed them in with the new lower Oring. They didn't take much pressure to pop them in place.

Was there a part number or designation for the caps you got?

[Aaron92SE]

Originally Posted by 92 Max

Was there a part number or designation for the caps you got?

I never got a part number from the guy I ordered it from. I just called him up, gave him photos and exact measurements and he said, "yeap, we got 'em!". So I said, ship 'em!

I am on my laptop right now. When I get home, I will look on my main computer for any notes that I wrote back when I did this about 3 or 4 years ago.

BTW, I failed to give you C&C's website:

http://www.ccfuelinjection.com/contact.html

[2k3TitaniumSe]

Juicey, how did the install go?

edit- just read your thread.

BTW, can anyone tell me how to relieve the fuel pressure in my 93 SE? And is this all I'll be needing: upper intake manifold gasket, o rings, and throttle body gasket?

Thanks again

[Aaron92SE]

Originally Posted by 92 Max

Was there a part number or designation for the caps you got?

Oh I forgot to get back to you. I looked on my home computer for any kind of number and there isn't one. He just sent me several caps in a plastic baggy without any kind of label. He said they don't normally do this, but he was very nice and willing to help me out after I told him my story.

Here are the pictures I sent him via email. They were sufficient for him finding the right pintle caps.

My KA24E has one missing. I can put a few thousand more miles on it no harm right? They just alter the spray pattern right? Its like 5 minuets to change them, but Ive already put 3 sets of O rings on those stupid injectors because the first 2 leaked (yes even with my high grade radio control truck diff lube, silcone based) And I dont want to put on another set.

On my max I had one missing on the set that came out of the car, but the 6 going in still had them. Id hate to see what it would do to the valve guides if it got caught between the valve and head. But they move pretty fast so its not to much of an issue aparently. Any one ever heard of a pintle cap causing some one to rebuild their head(s)?

Hmm have have 11 VG injectors, not all work (prolly 8-10 good ones of the 12 I had) can I take a cap off my VG inj and put it on my KA? They look similar but didnt have my VG inj near when I had the KA off.

Any way I guess if some one needs a VG cap PM me.

~Alex

[TJ_Max]

Originally Posted by Alex_V

Any one ever heard of a pintle cap causing some one to rebuild their head(s)?

Bump, my boy changed his injectors and one of the ones he had put in, like an idiot, was cracked. The pintle cap was cracked in half. It's still hanging on to the injector, but can he ruin something if the pintle cap falls off?

[Aaron92SE]

The pintle cap does not do anything to the spray pattern. It keeps the lower small Oring on! Which is definitely needed!

[2k3TitaniumSe]

Do I need to change a pintle cap with only one broken tab on it? It still holds the o ring in place. Also how do you pull them off?

And Aaron, why do your injectors have different pintle caps? I have that too, where some injectors have 4 tabs on the bottom and the others have 4 tabs on the bottom.

[92 Max]

Originally Posted by 2k3TitaniumSe

Do I need to change a pintle cap with only one broken tab on it? It still holds the o ring in place. Also how do you pull them off?

And Aaron, why do your injectors have different pintle caps? I have that too, where some injectors have 4 tabs on the bottom and the others have 4 tabs on the bottom.

One broken tab, if it doesn't get in the "O" ring area shouldn't hurt. They just protect the delicate jet area. The solid caps are aftermarket caps, usually put on after the injectors have been cleaned.

Hmm maybe thats my vacume leak then. That makes alot of sense no wonder why deleteing the emissions didnt help. Looks like some injector is going to get some RTV!

~Alex