isaakfarms Posted April 21, 2009 Share Posted April 21, 2009 Hello-I am working on a 92 CH613 with a 400 E7. I just recently had the head gaskets replaced and now the fuel injection lines on cylinders 1 and 2 are leaking. They are both leaking out of the head where the injection line is threaded in. I loosened the outside nut and tightened the stud thinking this would help stop the leak. The fuel is coming through the threads of the stud that the fuel line goes through into the head. Next I was told that this was common anytime the fuel lines are taken off and sometime the only way to get them to stop leaking is to replace the lines. So I bought two new injection lines for cylinders 1 and 2 and I installed them today. Guess what they both leak! I am thinking it is something on the mating surface of the injector where flanged part of the injector line meets. Is this possible? What should be my next corse of action? Thanks. Quote Link to comment https://www.bigmacktrucks.com/topic/9115-leaking-fuel-injection-lines/ Share on other sites More sharing options...
fjh Posted April 21, 2009 Share Posted April 21, 2009 Hello-I am working on a 92 CH613 with a 400 E7. I just recently had the head gaskets replaced and now the fuel injection lines on cylinders 1 and 2 are leaking. They are both leaking out of the head where the injection line is threaded in. I loosened the outside nut and tightened the stud thinking this would help stop the leak. The fuel is coming through the threads of the stud that the fuel line goes through into the head. Next I was told that this was common anytime the fuel lines are taken off and sometime the only way to get them to stop leaking is to replace the lines. So I bought two new injection lines for cylinders 1 and 2 and I installed them today. Guess what they both leak! I am thinking it is something on the mating surface of the injector where flanged part of the injector line meets. Is this possible? What should be my next corse of action? Thanks.You need to reseal the injectors!Buy 6 oring kits and do em all! Quote Link to comment https://www.bigmacktrucks.com/topic/9115-leaking-fuel-injection-lines/#findComment-34165 Share on other sites More sharing options...
isaakfarms Posted April 21, 2009 Author Share Posted April 21, 2009 You need to reseal the injectors!Buy 6 oring kits and do em all!Ok-So do I need to pull the injectors out to put the orings in? Quote Link to comment https://www.bigmacktrucks.com/topic/9115-leaking-fuel-injection-lines/#findComment-34187 Share on other sites More sharing options...
fjh Posted April 21, 2009 Share Posted April 21, 2009 Ok-So do I need to pull the injectors out to put the orings in?Yes, valve covers off you need a 5/16 fine bolt to pull them up and a 15 mm socket and 6 inch extention to pull the plug that holds them in! and the injection line has to be out. Quote Link to comment https://www.bigmacktrucks.com/topic/9115-leaking-fuel-injection-lines/#findComment-34193 Share on other sites More sharing options...
David Posted April 21, 2009 Share Posted April 21, 2009 Make sure the little washers are installed on the end of the injectors. If they arn't there or they get doubled, the line won't meet the injector correctly. Quote Link to comment https://www.bigmacktrucks.com/topic/9115-leaking-fuel-injection-lines/#findComment-34206 Share on other sites More sharing options...
isaakfarms Posted April 22, 2009 Author Share Posted April 22, 2009 OK so I called the local Mack dealer today, the one that I got the new lines from. I talked to the service manager about my problem, I asked if there was any kind of a oring kit or anything for where the injection line meets the injector. I was told that there was nothing, I was told that where the injection line mates with the injector it is metal on metal. His advice was to loosen the line again and then tighten the living crap out of it. So who is right? I guess I would think that there should be something to seat the line to the injector. Like I said before, I just had the head gaskets replaced, to my knowledge the injectors where never taken out-just the lines taken off. This is on a 92 E7 400. Thanks for the info and for the record I think you guys know more than the local service manager. Quote Link to comment https://www.bigmacktrucks.com/topic/9115-leaking-fuel-injection-lines/#findComment-34211 Share on other sites More sharing options...
Gambi80 Posted April 22, 2009 Share Posted April 22, 2009 . Thanks for the info and for the record I think you guys know more than the local service manager.I have the same problem...you must be in north central Illinois...? Quote Ever wonder how a blind person knows when to stop wiping? Link to comment https://www.bigmacktrucks.com/topic/9115-leaking-fuel-injection-lines/#findComment-34220 Share on other sites More sharing options...
fjh Posted April 22, 2009 Share Posted April 22, 2009 OK so I called the local Mack dealer today, the one that I got the new lines from. I talked to the service manager about my problem, I asked if there was any kind of a oring kit or anything for where the injection line meets the injector. I was told that there was nothing, I was told that where the injection line mates with the injector it is metal on metal. His advice was to loosen the line again and then tighten the living crap out of it. So who is right? I guess I would think that there should be something to seat the line to the injector. Like I said before, I just had the head gaskets replaced, to my knowledge the injectors where never taken out-just the lines taken off. This is on a 92 E7 400. Thanks for the info and for the record I think you guys know more than the local service manager.I am going to say Im right!Get new orings and washers for the injectors and replace em!He is right in regard to orings at the line it is metal on metal!Now having said that try what he said to do Back them off and retighten em if it don't work do what I said to do!I have seen this happen lots but you welcome to try the other method it will cost you nothing to try! Quote Link to comment https://www.bigmacktrucks.com/topic/9115-leaking-fuel-injection-lines/#findComment-34233 Share on other sites More sharing options...
isaakfarms Posted April 30, 2009 Author Share Posted April 30, 2009 Just a update-I spent four hours working on the injection lines that were/are leaking. I took everything loose and pulled the injection lines, cleaned and inspected the end of the lines and also made sure it was clean inside where the injection line meets the injector. I put everything back together, taking care to make sure the lines went back in nice and straight. All this work and guess what-they leak just as bad now as when I started. I am almost certain it is the orings on the injectors that is leaking fuel. I debated pulling the injectors but I pulled the valve cover off and it looks like the whole rack has to come out to get down to the injectors. That is more than I care to take on right now so I am gong to send the truck back to the mechanic that replaced the head gasket. I will update again when we find out exactly what is wrong. Thanks for all the advice. Quote Link to comment https://www.bigmacktrucks.com/topic/9115-leaking-fuel-injection-lines/#findComment-34552 Share on other sites More sharing options...
Mackpro Posted May 1, 2009 Share Posted May 1, 2009 Just a update-I spent four hours working on the injection lines that were/are leaking. I took everything loose and pulled the injection lines, cleaned and inspected the end of the lines and also made sure it was clean inside where the injection line meets the injector. I put everything back together, taking care to make sure the lines went back in nice and straight. All this work and guess what-they leak just as bad now as when I started. I am almost certain it is the orings on the injectors that is leaking fuel. I debated pulling the injectors but I pulled the valve cover off and it looks like the whole rack has to come out to get down to the injectors. That is more than I care to take on right now so I am gong to send the truck back to the mechanic that replaced the head gasket. I will update again when we find out exactly what is wrong. Thanks for all the advice.Its not that the injector line is leaking , its the o-rings on the injector it self that are leaking. The injectors have o-rings on them to keep the "return fuel" (fuel the injector dosent use) in a certain area so it can pass through drilled passages in the head and get returned back to the fuel tank. When the o-rings get damaged or go bad the return fuel rises up and into the area where the injector line comes through the side of the head and meets the injector and the fuel has no where to go but pass the threads on the injector line and down the side of the engine. We see this all the time. In the 2002 and up CCRS and ASET engines there is no fuel return in the heads/injectors. 1 Quote Link to comment https://www.bigmacktrucks.com/topic/9115-leaking-fuel-injection-lines/#findComment-34585 Share on other sites More sharing options...
Maxville Truck Posted May 1, 2009 Share Posted May 1, 2009 I am almost certain it is the orings on the injectors that is leaking fuel. I debated pulling the injectors but I pulled the valve cover off and it looks like the whole rack has to come out to get down to the injectors. That is more than I care to take on right now so I am gong to send the truck back to the mechanic that replaced the head gasket.You shouldn't have to pull the rack....Dont feel bad One of my drivers overrevved a e-6 4 valve going down ahill and busted the crank. Truck is oldest n my fleet it will get a hammer in the head.... Quote Link to comment https://www.bigmacktrucks.com/topic/9115-leaking-fuel-injection-lines/#findComment-34598 Share on other sites More sharing options...
isaakfarms Posted May 13, 2009 Author Share Posted May 13, 2009 Well the mechanic got my fuel leak fixed. He pulled the injectors out and he found a small amount of corrosion in the cup of the injector where the injector line meets. He cleaned the mating surface with a scotch brite pad and that seemed to do the trick. He also changed the orings right away. Thanks for all the help. Quote Link to comment https://www.bigmacktrucks.com/topic/9115-leaking-fuel-injection-lines/#findComment-35148 Share on other sites More sharing options...
bobcotkg Posted May 14, 2009 Share Posted May 14, 2009 I had some lines off the 237 the other day. put them back on and they leaked. I found then threr were little copper washers between the injection line and injector that were out. Put them back in and it is fine. I've never seen or heard of such a thing. Is that a common thing I just haven't ran into yet?Bob Quote Link to comment https://www.bigmacktrucks.com/topic/9115-leaking-fuel-injection-lines/#findComment-35191 Share on other sites More sharing options...
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