Pre-Power Stroke Diesel (7.3L IDI & 6.9L) Diesel Topics Only

Fuel leak from back of engine!!

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Old 03-02-2011, 07:40 PM
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Fuel leak from back of engine!!

Hello all,I have a 93 F250 with a 7.3 liter with 175,000 miles on it,i have had it since new,anyway,i have this fuel leak on the truck,the fuel is coming down right behind the back side of the starter.. it is almost a stream but not quite.I have looked up top & cant see any leaking from there.And i cant see where it is coming from down below.Can anybody give me an idea where to go from here..ANY help would be GREATLY Appreciated!!
Thanks,Reddawg
 
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Old 03-02-2011, 08:09 PM
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If your O-rings aren't leaking, check around your IP real well. It has a weep hole and can leak under the intake and travel to the back of the motor.
 
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Old 03-02-2011, 08:13 PM
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Any leaks on top of the engine will drain down that spot. If it is fuel, I would check the return lines and under the injector pump. It has a weep hole that can leak if the internal seals go bad.
 
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Old 03-02-2011, 09:48 PM
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I bet it is a return line like the rear crossover line or the hex t fitting in the return system from 7 & 8. Either that or its guaranteed to be the filter to IP feed line on center of the IP. Get in there with some cleaner and dry it all out then have some one idle it while revving and watch with a bright light. Look across the truck and see the filter to IP hard line and you might just see your problem, shared that same dripping stream once and it was just a loose nut.
 
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Old 03-03-2011, 01:22 PM
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Hey I have a 1994 7.3 also IDI an everytime I have a leack it has been the return line capes that fit over the injectors I keep a few in my glove box an a 5/8 wrench I also have found that the rubber lines crack an leak also Hope it helps. Rick
 
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Old 03-03-2011, 02:16 PM
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Well,when i wrote this yesterday, i did NOT look close enough from up top & i have 3 Injectors leaking,its amazing what i can find when i remove the air cleaner..so i will replace the o-rings on those 3 injectors,and go from there!!Thanks for you help ,i will get back with you and give you a report..
 
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Old 03-03-2011, 06:09 PM
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Hello again,well,i just got done replacing the o-rings on the injectors,got a multi pack from the local parts store,the ones i used were size 19/64x37/64,they seemed a litle bit tight,but they fit,Now the injectors are leaking alot worse than before.What i need to know is what size o-rings do i need for this job?
Thanks again for ALL the info..
Reddawg
 
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Old 03-03-2011, 08:40 PM
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The industrial # for the o-rings you need is #111 - actual dimensions are 7/16" ID, 5/8" OD, 3/32" width.
 
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Old 03-14-2011, 09:33 AM
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For best results you should replace them all. If you only remove a couple, chances are you will disturb the others enough that they will start leaking as well. Get viton rings if you can, they resist leaking so much better than standard buna rubber rings. I have removed my caps 3 times and my rings still dont leak.
 
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Old 03-14-2011, 09:46 AM
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And remember to lube the with something (vaseline, oil, something) even after I replaced my o-ring they still leaked because I had not lubed them and they tore a little. Its also best to get all the lines connected before you push the caps to their final position because if you move the caps at all once they are pressed down, they will leak. Still wonder how they got them leak free from the factory - mine had no fuel leaks at all until 105K, and the lines and caps were original painted grey!
 
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Old 03-14-2011, 03:38 PM
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Thanks for ALL the advice fellas..I ended up getting the install kit from Pensacola Fuel Injection[url]http://pensacoladiesel.com/83-89-6-9l-7-3l-injector-installation-kit.html[url],which had New rings,hoses,caps,everything i needed to get the job done correctly.And by george it works!!And i am no way very Mechanial,so anybody wanting to do this job who has doubts,dont!it is a piece of cake!!
THANK YOU you ALL again..
Until next time
Reddawg
 
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Old 02-15-2012, 04:54 PM
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Guys: I have the same fuel leak as 1Reddog12R. I have a 1994 7.3 IDI 'K' engine. My problem is the fuel is coming down the back of the block and we can't find where it is coming from.
I can start the engine and if it leaks ( which is nearly a steady stream) I can shut off the engine and restart it and it may or may not leak. We have checked all injectors, lines, etc. I looked under the turbo and it is all dry.
When the fuel does leak, it drips off the seam between the motor and transmission, as well as off the crossover pipe.
Any ideas where it could be coming from? We have spent several hours trying to find the leak but nothing. I need help from the PRO'S - you guys!
 
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Old 02-15-2012, 06:38 PM
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Toucan2003,

You would be better served by starting your own thread, this is an old one.

However, the valley pan dumps out back there so ...

Couple things to look at, the fuel returns tie together at the top back of the motor ... check them out.

Also place a clean piece of paper under the Injection pump, take note of it's position, then run the motor for a few, shut it off, carefully pull the paper out looking for fuel drops on it.

-Enjoy
fh : )_~
 
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Old 02-15-2012, 07:26 PM
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Festus:
I started a new thread as you suggested. I posted my problem including responding to your suggestions.
Thanks,
Fred Smith
 
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Old 09-26-2022, 12:47 PM
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Solved

Originally Posted by 1reddawg12r
Hello all,I have a 93 F250 with a 7.3 liter with 175,000 miles on it,i have had it since new,anyway,i have this fuel leak on the truck,the fuel is coming down right behind the back side of the starter.. it is almost a stream but not quite.I have looked up top & cant see any leaking from there.And i cant see where it is coming from down below.Can anybody give me an idea where to go from here..ANY help would be GREATLY Appreciated!!
Thanks,Reddawg
ITs the upper hose coming out of the pressure regulator. They are plastic trash. My girlfriend and i got stranded and fixed it with two hose clamps and a siphon pump hose. BING BONG
 


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