7.3L IDI Injectors?

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Apr 29, 2003 | 06:46 PM

Gr8ride

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From: Texas USA

7.3L IDI Injectors?

Howdy,

I have a 93 F250 7.3L diesel w 154,000mi.
I need to replace two injectors, is this a huge pain in the you know what to do? Also, should I just replace the two or should I replace all 8?

Thanks,
Gr8ride

Apr 29, 2003 | 08:11 PM

bilder12

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From: Northeastern Pa - USA

7.3L IDI Injectors?

How did you determine which 2 to change?
with 150k miles on it, you may as well take them all and have them tested --- replace what is bad and you will prob find them all in need of repair.
they just unscrew from the head, make sure the copper washer is out of the hole and a new one is on the replacement nozzle.
BE CAREFUL reinstalling them ... dont knock the tip off or bend it.
You can hold the new copper crush washer in place with never seize around flange of the nozzle - enuf to hold is good.
Torque new nozzle and reinstall fuel line ... loose to let fuel come up faster ... and tighten when fuel flow is up to snuff.

Apr 29, 2003 | 08:36 PM

Gr8ride

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From: Texas USA

7.3L IDI Injectors?

Hi bilder12,

I figured out which injectors where bad or weak by loosening the fuel supply line to each one with the engine running. On two of the injectors it didn't make a difference when I loosened them, but on all the others you could tell the difference.
The engine has been running rough for a while now, but recently gotten worse, that's why I decided to check the injectors.
While I have the injectors out should I do anything to the injection pump? Is there anything else that I should while I have the injectors out?
At idle the truck has a noticeable amount of gray smoke and when pulling hard, hardly any smoke if any at all comes out. Is this good?

Thanks,
Gr8ride

Apr 30, 2003 | 10:09 AM

Freight Train

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From: Waterbury, CT.

7.3L IDI Injectors?

Sounds like the springs are getting hard in those injectors. They don't fire right at idle, but start to work a little better when the engine is revving. That would explain the smoking pattern. I would change all 8, if you found 2 bad ones doing an injection balance test, then more than likely, the rest will follow soon. They're cheap enough to do so, just be thankful it's not a powerstroke, those puppies cost around 300 each and take a hell of a lot longer to change than ours do.

When you take the injector line off, only move it to the side enough to get the leakoff tee off and take the injector out. You don't want to start making leaks back at the pump.

Another note. The new injectors should come with return o-rings on them already(mine did), after the injector is installed, use vasoline on your fingertips and just give a wipe on the o-rings, that'll make the leakoff tee's go on very easy. Don't use any grease, or penetrating oils, I wouldn't diesel fuel for this either.

I did mine in 4 hours, but I have a turbo on top of the motor that makes working on these, and the glowplugs a lot of fun.

Let us know how you make out.

May 6, 2003 | 04:55 PM

Gr8ride

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From: Texas USA

7.3L IDI Injectors?

Hi again,

I ordered 8 new injectors, they should be here Friday (I hope).
Now for my next question, from what I have read I need to use a nozzle seat cleaner to clean out the nozzle bore in the head.
I have Ford's part number (T83T-9527-A) for it, so I called Ford and asked them to order it for me. Ford said that they don't know what it is and the part number doesn't exist.
So, any idea on who may have one or somthing like it and do I even need it?

Thanks,
Gr8ride

May 6, 2003 | 08:14 PM

bilder12

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From: Northeastern Pa - USA

7.3L IDI Injectors?

all that tool does is clean any hardened carbon from the bottom of the hole that the nozzles sit in. Just be sure to get out the copper crush washer and you should be good to go. Use air pressure and air gun inserted past the bottom of the hole and clean out anything that may be in there ... similar to cleaning out the spark plug hole in a gasser. You can use a flash light to look down the hole to see if there is junk in there.
MAKE SURE YOU REINSTALL A CRUSH WASHER ON THE BOTTOM OF THE NOZZLE

May 10, 2003 | 01:24 PM

Gr8ride

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From: Texas USA

7.3L IDI Injectors?

Howdy again,

I replaced all 8 injectors, and what a difference it makes. It doesn't shake at idle anymore, it's not blowing smoke out anymore and now it gets up to speed a lot faster and it actually turns a few less rpm than it used too, to go the same speed.

I got all the leak off tees installed with out any trouble for once.
I desided to replace the valve cover gaskets to get rid of a couple of oil leaks.That was the hardest thing to do and that wasn't hard at all. It started up on the first try, I was kinda suprised but very happy.
Thanks for all the help guys