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fuel in coolant

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I got one in today for a strong fuel odor and degas bottle overflowing. Brought it in and sure enough fuel and coolant were overflowing out of the cap. The first thing that came to mind was injector cups just remembering that happen on a couple 7.3s. Called the hotline just to make sure i was right because i couldnt find anything in the PCED or workshop manual on this.Hotline said i was absolutley right and told me the best way to check them is to pull all 8 injectors, clean out the bores in the cups, rub palmolive down in the cups , spray them with water to activate the soap and pressurize the cooling system. He said then to look in the bores for bubbles also on the heads for cracks in the castings above the cups.Well my questions to you guys are that the WSM says you have to pull the heads to install new injector cups,Is this true? Also is this what you guys do to find the leaking cups?? Any help or advice always appreciated!

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We had one of these arrive in my shop today as well. The tech I assigned this to also called the Hot-Line (Hi guys! /forums/images/%%GRAEMLIN_URL%%/borgsmile-1.gif) and was given the same instructions. We had another discussion about this and tossed around the idea that you would have to have a leak at the cup AND at the lower fuel o-ring. Unless you have a crack along the injector bore I doubt you will see anything but I suppose any of the ideas you read about could be helpful. Since I love UV tracer dye so much, I might suggest adding dye to the cooling system, remove the injectors and pressurize the system and look for a leak with a black light. I have my doubts about the bubble thing - not enough coverage, not enough soap, how do you know you sprayed it down well enough, you get the picture. /forums/images/%%GRAEMLIN_URL%%/wink.gif

 

See THIS TOPIC first, then click on over to THIS TOPIC and pay attention to the pictures of Bruce's awesome cutaway of a 6.0L cylinder head. The Hot-line's suggestion is a noble attempt to find the leak...

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In order for fuel to enter the cooling system on a 6.0L, I believe that the injector cup(s) AND the lower o-ring(s) has to have failed, the likelihood of which are highly slim as illustrated in this photo:

Posted Image

 

Below, is a more complete view of the 6.0L cutaway that gives you a better idea of which passages are for fuel and coolant:

Posted Image

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thanks for the links to those topics very helpful i see what you mean now im prolly gonna end up puttin heads on this thing by the way bruce's cutaway is titties.

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I remember reading somewhere about plugging in the block heater as the leak is more likely to show up if the engine is hot. I can't remember if it was for the 7.3 or the 6.0, but likely will help in either case. /forums/images/%%GRAEMLIN_URL%%/smile.gif

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TRY REMOVING THE FUEL LINES FROM THE FILTER SIDE OF THE SECONDARY FUEL FILTER, REMOVE THE THERMOSTAT HOUSING AND PRESSURIZE EACH SIDE ONE AT A TIME WHILE LOOKING FOR BUBBLES IN THE THERMOSTAT CAVITY. SHOULD HELP IN AT LEAST LOCATING WHICH SIDE IS FAILED. CAN ALSO PRESSUREIZE THE DEGAS BOTTLE WITH THE FUEL LINES OFF THE SECONDARY HOUSING AND LOOK FOR THE FUEL LEVEL TO MOVE IN THE LINES. IF ALL ELSE FAILS REPLACE BOTH HEADS.

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Thanks Keith! yup actually works. Depending on the size of the injector cup crack might have to keep the air pressure you use on for as much as 30 minutes.Another help is when you remove the thermostat keep the coolant level even to the top of the thermostat mounting. Some small leaks just move the level.

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YOU DONT REALLY NEED AN ADAPTER TO SEAL THE THERMOSTAT HOUSING. YOUR LOOKING FOR ANY BUBBLES OR LEVEL MOVEMENT IN THE THERMOSTAT CAVITY WHEN THE FUEL SIDE IS PRESSURIZED AND REALLY DO NOT WANT ANY TYPE OF INTERFERENCE. I ALSWYS LOOK AT TRYING TO KEEP THE ENGINE TOGETHER AS MUCH AS POSSIBLE DURING DIAG BECAUSE ONCE YOU GET IN THERE TOO DEEP " YOUR COMMITTED" AND MAY NOT HAVE A CHANCE TO GET MORE DIAG IN WITHOUT REASSEMBLY.BY TODAYS EVENTS BETTER HAVE ENOUGH TESTING DONE OR YOUR POCKETS (ASS) ON THE LINE. IF YOU DONT FIND ANYTHING YOU CAN ALWAYS REMOVE ALL INJECTORS AND PRESSUREIZE THE COOLING SYSTEM " LIGHTLY" LOOKING IN INJECTOR BORES WITH BOROSCOPE. ONE THING YOU HAVE TO CALL IS HOW ARE YOUR DIAG METHODS WORKING FOR YOU ON THIS ENGINES PROBLEM. I LEAVE ABOUT 1-1.5 HOURS THEN IF NO GO STEP BACK AND LOOK AT THE WHOLE PICTURE. REALIZE YOUR PULLING THE ENGINE IF ITS THE HEADS ON AN ECONOLINE. MAY BE WORTH THE CALL TO JUST PULL THE ENGINE AND DO BOTH HEADS. OH KEITHS METHOD OF LIQUID TIDE WORKS GREAT! AND HES RIGHT "SNUGGLY FRESH".

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I had one just last week. It was an 07 with about 35,000 miles. I remove the filter housing removed the fitting in the filter housing that the fuel line attaches to Used a female air hose addapter the ones that are on the ends of you air tools. It threaded on pretty good to the fitting attached it to the fuel line with warm engine and block heater plugged in I removed the t-stat without draining coolant first to keep coolant level near top of port. Hook up shop air to fitting after about 20minutes I had bubbles out coolant from left head. I only replaced 1 head witch was ok due to being unable to remove cab. And oddly enough I have a 7.3L in my stall right now with same probelm. But years ago I built a Bridge of sorts to remove cups with out pulling heads.

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I had one just last week. It was an 07 with about 35,000 miles. I remove the filter housing removed the fitting in the filter housing that the fuel line attaches to Used a female air hose addapter the ones that are on the ends of you air tools. It threaded on pretty good to the fitting attached it to the fuel line with warm engine and block heater plugged in I removed the t-stat without draining coolant first to keep coolant level near top of port. Hook up shop air to fitting after about 20minutes I had bubbles out coolant from left head. I only replaced 1 head witch was ok due to being unable to remove cab. And oddly enough I have a 7.3L in my stall right now with same probelm. But years ago I built a Bridge of sorts to remove cups with out pulling heads.

Did you regulate the pressure down to about 56 psi? I believe shop air pressure is about 120 to 150 in most shops.
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/forums/images/%%GRAEMLIN_URL%%/cover.gif

 

EASY! Let's not get carried away, this is not a high pressure oil system we are talking about now! Tim Taylor would be proud though. /forums/images/%%GRAEMLIN_URL%%/notworthy.gif

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Maybe that would be the easy way to remove the cups? Blow'em out!

 

Ker-bang! /forums/images/%%GRAEMLIN_URL%%/flamethrower.gif /forums/images/%%GRAEMLIN_URL%%/hammer2.gif

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  • 2 weeks later...

Ive pumped 100psi into several trucks now to find my fuel in coolant concerns. plug the block heater in and get it good and warm too. I think everyone Ive had has been the right head only. this is what hotline was directing a while back before the removing injectors and spraying soap in the holes

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  • 4 weeks later...

One of our techs started using a round cylinder that the tap will slip through.He then screws the tap in the cup and screws a threaded rod in the end of the tap.He then uses a washer and a nut and pulls it out just like the tool for removing 5.4l spark plug ends that break of in the heads of new style f150's.

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We got crafty like that on a 2006 6.0L ambulance where the cup on #5 cylinder had to be replaced because of a combustion leak. We took a threaded rod from one of my 2-jaw pullers and the nut and bearing from my P/S pulley installer and threaded it in the tap like you mentioned. Then we took two steel plates from our press and laid them across the rocker housing and they just cleared the rocker arms. We were able to crank on the nut with a wrench and whadda ya know! The cup came out. Amazing the tricks we all come up with - eh? But you mentioned a tube and if I recall idea that came across my mind - one that would sit around the opening of the injector bore and the nut would push against it. We didn't have anything like that but t is a great idea and it would allow for a shorter rod which would allow this to work on the back cylinders where working clearance is not available.

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