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Engine Specific Info and Questions => IDI Engine => Topic started by: lukitas on November 25, 2016, 11:21:41 am
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hey guys today i changed my fuel lines/fuel filter and this is how it looks when the car is running. Theres a huge air bubble on the line. I am not sure if its the pump going bad or what it is. Also the return line has barely any fuel and between the injectors theres like no fuel on the hoses.
I tried using a gallon jug with diesel and it seems like its the same. Is there anything i can try to see if its the pump that is gunked up or what?
Thanks in advance.
https://www.youtube.com/watch?v=C025jDmYmB8&feature=youtu.be
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Your problem is the cheezy screw type hose clamps you are using. They work OK for pressure with neoprene hose but they leak air when under a slight vacuum, like when the diesel is trying to drain back into tank or when the IP is sucking fuel.
That clear plastic hose is particularly hard to seal. There is a reason that the factory used press in fittings in a hard plastic line.
The best answer is to use 2 wraps of safety wire installed with the proper safety wire pliers.
Crimp-on hose clamps seem to work OK with neoprene lines, but I doubt they would seal well enough on plastic tubing.
The screw hose clamps tend to squish up the clear plastic hose a bit under the screw area and put a tiny wrinkle in the hose which is just enough to get it to leak air. It is often not enough to leak fuel, though. And fuel is never under pressure between the PF and the IP.
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i found when i put clear lines on the clamps were especially difficult, to tighten them ,
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The jug test is a good start. I'd repeat the test, though, taking a good look at the amount of fuel circulating in and out of the IP... it should be a generous amount , like a liter a minute or so.
I can't see any typical fuel flow in the video, so I'm suspecting the OUT bolt in the IP is plugged with crud/WVO/whoknowswhat...
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i used clamps cause thats what the PO had in there it was alot worse than what i did. Also i think i found the problem. The Banjo return bolt was supper clogged couldnt even blow through the little fitting from the injectors. So i clean both banjos really well the return one and the feed one from the pump and it seems like fixed it. the only issue i have is that the small return lines from the injectors have air in them i have to release the air but i didnt get to it yet. Also i wanted to clean the banjo from the fuel filter housing but i couldnt get them off i sprayed some pb blaster to see if it will help.
Also the clear lines are from home depot it was like 3 bucks for 10ft. I dont mind changing them often. But the 1/8 from the injectors are "fuel rated" lines. Also i dont use biodiesel so they should be good.
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Also the clear lines are from home depot it was like 3 bucks for 10ft. I dont mind changing them often.
so i dont think any of these phrases are cooperative with 'fuel rated';-home depot, -$3, or not marked as fuel. and its your main flow/fuel line, -to pump.
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Also the clear lines are from home depot it was like 3 bucks for 10ft. I dont mind changing them often.
so i dont think any of these phrases are cooperative with 'fuel rated';-home depot, -$3, or not marked as fuel. and its your main flow/fuel line, -to pump.
i bought that feed clear from home depot other people in other forums used it and they said nothing happened. I guess time will tell. Also the Return lines on the injectors was labeled "Fuel line".
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yea thats just clear tubing; a handyman would use, for god only knows, a simple, what. running a light amount of water thru? stuff like that.
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I bet that stuff will get yellow and stiff as a stick in short order. Not fuel rated so I would only use as stated, by a handyman to run water through.
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Don't worry too much about using clear vinyl from HD... Fuel can't hurt it... it does get stiff in the winter tho, and that can cause leaks by the fittings. As stated, it might get yellow fast too.
If you want better, you can get "tygon" or polyurethane transparent lines from industrial suppliers or speed shops.
The small injector return lines usually have a little air in them... no big deal. However, if they are leaking, they stink and can let in air when the engine is off.
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So I think I found the issue. I changed all the hoses and the return banjo bolt was clogged up I couldn't even blow air threw it. so I cleaned that up and the in banjo and it seems to be running fine now. we shall see how it goes. I haven't driving it much due to the cold weather.
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And here we were chasing an air bubble at first. Air can't leave if fuel can't either. Glad you checked that. It is a normal first place to go for fuel delivery problems. Odd none of us thought to send you there.
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... Odd none of us thought to send you there....
Ahem...
I can't see any typical fuel flow in the video, so I'm suspecting the OUT bolt in the IP is plugged with crud/WVO/whoknowswhat...