Injector Swap Writeup for the 4.0L - Page 9 - JeepForum.com
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Unread 05-08-2013, 06:39 PM   #121
nysm1
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Now that I wouldn't be able to help with that, but it shouldn't differ to much... Just search on the forums more, something HAS to be here

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Unread 05-08-2013, 07:33 PM   #122
billybooster2
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1983 CJ8 
 
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There are only 4 thongs inportant;

1. Disconnect battery
2. Relieve fuel pressure at rail. Looks like a tire valve. Press it in and fuel spurts for a second.
3. Remove fuel lines from rail. There are two. One in. One out.
4.unscrew rail from manifold.
5. Rock rail with attached injectors out of manifold
6. Remove injectors. Follow previous procedures regarding caseline, silicone or other lubricant
7 reverse, reattach.
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Unread 05-08-2013, 08:01 PM   #123
Jeepuzzled
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Quote:
Originally Posted by billybooster2 View Post
There are only 4 thongs inportant;

1. Disconnect battery
2. Relieve fuel pressure at rail. Looks like a tire valve. Press it in and fuel spurts for a second.
3. Remove fuel lines from rail. There are two. One in. One out.
4.unscrew rail from manifold.
5. Rock rail with attached injectors out of manifold
6. Remove injectors. Follow previous procedures regarding caseline, silicone or other lubricant
7 reverse, reattach.
My concern is the fuel regulator that is attached to the front end of the rail. Do I pull it off the rail, or leave it in place connected to the rail and instead disconnect all the other tubes connected to it.
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Unread 05-08-2013, 08:45 PM   #124
billybooster2
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Leave it on. It only does something when pump is on.
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Unread 05-09-2013, 01:55 PM   #125
dukie564
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you do not have to remove the pressure regulator, just pull off the vacuum line. For the fuel lines squeeze the white tabs in and pull on the hose to remove them from the rail. If the injectors are rebuilt they should already have new orings on them. Rest of the procedure is the same.
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http://www.jeepforum.com/forum/f22/project-danger-cart-xj-1297118/
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Unread 05-10-2013, 01:54 AM   #126
Jeepuzzled
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Quote:
Originally Posted by dukie564 View Post
you do not have to remove the pressure regulator, just pull off the vacuum line. For the fuel lines squeeze the white tabs in and pull on the hose to remove them from the rail. If the injectors are rebuilt they should already have new orings on them. Rest of the procedure is the same.
Thanks for your reply. The 89 Comanche is a little bit different than the 95 Sport. I left the regulator on the rail, but I had to disconnect the fuel lines at the rear of the rail ( fuel input), and at the (front) regulator as well ( fuel return). The fuel lines use a 'quick connect' technology that requires replacing the clip, O rings ( 2) and spacer whenever you pull a fuel line apart. There is supposedly a Quick Connect repair kit that has the parts and plug tool for reinstallation, but just try locating one of those kits! That kit has a disposable plug that acts as a mounting tool to reinstall the O rings, spacer and clip on each fuel line connection. I tracked down the separate clips and O rings ( made by Dorman and available on Amazon), but nada on the installation plug.

UPDATE: Morris 4x4 supposedly has this kit. Their Part # 83502745 fuel line repair kit 5/16' fuel line $8.99 . I have ordered a couple of them and will give a future update on how well they work. It does come with the installation mounting tool.
UPDATEII: I received the kits and they worked like a charm to connect my fuel lines in less than 5 minutes. Plus, I now have the two plastic mounting tools to use for O-rings, spacers, and clips if I ever need to disconnect fuel lines in the future. Thanks for your help, folks!
fuelregoutlet1.jpg   fuelregoutlet2.jpg  

Last edited by Jeepuzzled; 05-18-2013 at 07:06 PM.. Reason: Update
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Unread 06-30-2013, 01:33 PM   #127
hocgreen
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Quote:
Originally Posted by jakecarder View Post
Subscribed page saved. great write uo. used it today to diagnose cylinder one missfire. switched injectors between one and two
I've been looking EVERYWHERE! Can you (or anyone) tell me which injector is injector #1? That injector is bad and I need to swap her out quickly. I am planning on doing this when I have the scratch to drop but right now spit and glue.

Anyone?
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Unread 06-30-2013, 03:00 PM   #128
billybooster2
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Quote:
Originally Posted by hocgreen

I've been looking EVERYWHERE! Can you (or anyone) tell me which injector is injector #1? That injector is bad and I need to swap her out quickly. I am planning on doing this when I have the scratch to drop but right now spit and glue.

Anyone?
#1 is front of engine
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Unread 09-03-2013, 10:20 AM   #129
Terry777
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Spark plug gap

Hey, nice thread thanks for all the detail.

I already posted this question in the engine section but everyone is going to see it so worth a shot here, will a spark plug gap other than the specified plug gap in the Haynes manual (0.035 SAE or 0.89 MM) give any better combustion with the new misting gas?
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Unread 09-03-2013, 06:37 PM   #130
billybooster2
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I doubt it!

Stick to 35
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Unread 12-01-2013, 09:24 AM   #131
TJ Frank
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Subscribed page saved. great write up
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Unread 12-01-2013, 09:36 AM   #132
brokeagin
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In my opinion you will need to upgrade the ignition system in order to increase plug gap...
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Unread 12-02-2013, 09:14 AM   #133
Mattmax
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injector swap writeup for 4.0 L-Jeepforum.com

Have been replacing the injectors on my 87 4.0 L Cherokee, and chipped the bases off some of the electrical connectors. Do I need new connectors if the old are electrically intact?
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Unread 12-02-2013, 09:48 AM   #134
Mattmax
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great writeup!
Have been replacing the injectors on my 87 4.0 L Cherokee-Laredo, and chipped the bases off some of the electrical connectors. Do I need new connectors if the original are electrically intact?
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Unread 12-02-2013, 01:01 PM   #135
dukie564
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what do you mean by "bases" of the connectors?

If they stay connected and have good terminal contact, i don't see the need to replace them
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1995 XJ Cherokee Sport
4.5" Homebrew Lift, 4.0L HO I-6, AX-15, NP231, D30(Open)/C8.25(Locked)
33x12.5 Mickey Thompson Baja MTZ Tires, 283,000 mi and runnin' strong
http://www.jeepforum.com/forum/f22/project-danger-cart-xj-1297118/
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