hey guys i just bought my first diesel, 1993 7.3l IDI

it drives like a beast and has low miles to be a 1993, 175k

i have two issues that worry me and need help with

first is that i noticed it smelled fuel real strong and noticed that one of the injectors seems to be leaking out of the return lines and then it looks like their is a small amount of fuel around all of the injectors where they go into the head

is that normal ? i dont think it is but wanted to ask

second is that at least once a day it is a pain in the booty to start
would the injectors leaking cause that or what should i be looking at to solve that issue ?

any help would be great

thanks

 

From what I've been told the return lines leak if you even look at them the wrong way, chances are you have some broken o-rings, just get a new return like kit.


As for the hard starting that could be a number of things, return lines, bad injector, bad fuel filter.

If you plan on getting a return like kit I'd get some new BB code injectors just to be safe (and they give you a little pep in your step too)

 

check your positive batery cable my dads did the same thing

 

you cant list a new rig in here like that and not post pics!

yeah.your fuel is draining back to the tank due to leaky return lines.
i'm with both above posters.
good corrosion free contact points and cables are a must.
then you want to test the glow plugs too.-only replace with motorcraft gp's (seek the sticky threads at the top.)
search for,and test your coolant for proper levels of SCA's.-if it doesn't look clean.flush it asap.
welcome to the classic Navistar Iternational IDI!

 

Injector Installation Kit

Many prefer to toss the o-rings in the kit (and I highly suggest you do) and use these Viton Return O-Rings - McMaster-Carr Item 9464K24, Viton is impervious to Diesel.

For the Injector Installation Kit installation You can follow Starmilts Humorous Fuel Return Replacement Procedure, I like to cut the 6 pieces between the Injectors to 4-1/16", Use a sharp razor blade to cut the hose and Vaseline to lubricate the o-rings.

For proper fuel system bleeding you can use steps 1 through 4 and 13 through 15 of the Fuel Filter Replacement.

-Enjoy
fh : )_~

 

Since no one told you, fuel on top of the motor is not normal.

I do agree with the leaking return lines being your problem though.

 

thanks for all of the help guys

got the return lines o-rings replaced and the fuel mileage is way up from what it was
cant imagine why, lol

going to change the fuel filter in the morning and the oil

next will be the GPs and injectors

i will try and post up some pics this weekend

thanks again guys

 

Do yourself a favour, change the fuel filter and oil at different times.... meaning that change one, get it running for a bit, then change the other. It's not a huge problem with these trucks, but I read a bulletin at a shop last night about some newer trucks having bearing issues from lack of oil while cranking to get fuel through the system when both were changed at the same time.

 

thanks for the heads up. i was planning on doing the fuel tomorrow and the oil on saturday

but good to know that anyway

 

Warm the truck up real good before changing fuel filter then fill the new filter with diesel kleen before installing and you wont have to crank it near as much to get her running.

 

Hello there, I'm having this problem as well. Just a minor difference in the symptoms. It fired and stalled after I did my lines. Is this likely to just be my fuel filter?

 

that's because the suction in the line was lost when you broke it....unhooked the lines.there is supposed to be a check valve built into the filter head of the updated 7.3 style filter head.....but lol.
so your fuel drained back on you.you'll need to prime the system.
crank for 15 full seconds then walk away for 2 full minutes to let the starter cool.crank for another full 15 seconds or until the engine runs of course.continue the 15 second crank/2 min cool down until she fires up or the batteries run dry whichever comes first.

 

She fired right up. What a relief I thought I was going to have to do a rebuild on my injector pump with less than 3000 miles on its last rebuild. Finiky old girl.

 

Yes, there is. And as far as I can tell, by now it's gone/shot. On /all/ of our trucks.
This is probably why I've had such good luck adding an aftermarket check-valve to the system.

 

Boy this thread sure throws into contrast the guys that arent around anymore.