quick return line question
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Postmaster
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quick return line question
on my 87 E350, i changed the return lines and caps about 6 months ago, and its been great until now. i again have classic symptoms of air intrusion appearing after only a few hours. it happened once a week ago and then twice today. i looked as close as i could from under the hood and didn't see any fuel leaking out, but can't see too well from the front in a van.
my question is if 6 months is a somewhat normal life for return lines or if i likely have another problem in the system, such as a damaged line downstream somewhere
tonight i'll pull off the inside engine cover and take a closer look to see if i can find a broken hose clamp or anything else obvious
my question is if 6 months is a somewhat normal life for return lines or if i likely have another problem in the system, such as a damaged line downstream somewhere
tonight i'll pull off the inside engine cover and take a closer look to see if i can find a broken hose clamp or anything else obvious
Posting Guru
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From: Peterborough, Ontario
Couple things, did you use viton o-rings or the standard ones included in the kits? Viton will last longer, but they also harden in time with heat. Either way, any nearby work can disturb things enough to cause a leak to start.
Also, look at the fuel filter base to see if there's any sign of a leak at the heater connection, another spot for air intrusion.
Other places that air leaks can develop are the fuel lines (steel can rust through for example) O-rings in the plastic line connections, cracked pickup tubes, or simply too low on fuel in the tank.
Also, look at the fuel filter base to see if there's any sign of a leak at the heater connection, another spot for air intrusion.
Other places that air leaks can develop are the fuel lines (steel can rust through for example) O-rings in the plastic line connections, cracked pickup tubes, or simply too low on fuel in the tank.
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Postmaster
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i used the standard o-rings (didn't know about the others)
a quick parking lot inspection found a little fuel coming out around the steel line that goes to the front of the IP, so i'll tighten that down again. but its never given me starting issues in the past, just fuel on the outside.
last week i was under it and noticed the rubber lines by the rear tank looked pretty old, so i'm thinking the rubber lines to both tanks are in order, though not sure if thats the cause of my leak.
i was thinking 6 months without being disturbed was a bit too soon for the injector lines to be going bad, so i was starting to think somewhere downstream. i'll study everything on it tomorrow and see what i find
thanks for the reply
a quick parking lot inspection found a little fuel coming out around the steel line that goes to the front of the IP, so i'll tighten that down again. but its never given me starting issues in the past, just fuel on the outside.
last week i was under it and noticed the rubber lines by the rear tank looked pretty old, so i'm thinking the rubber lines to both tanks are in order, though not sure if thats the cause of my leak.
i was thinking 6 months without being disturbed was a bit too soon for the injector lines to be going bad, so i was starting to think somewhere downstream. i'll study everything on it tomorrow and see what i find
thanks for the reply
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Postmaster
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well i got into it tonight a little bit, and found that the line i mentioned in my past post was tight, but the "L" fitting with which it goes into the IP has always been a little wobbly against the IP. i did notice that both ends of the line from the filter to the IP were loose, and a significant amount of fuel had been leaking into the valley and dripping off the back-right of the engine. so i tightened those down and spent 2 cans of carb cleaner to wash off all the mess so i can see whats happening next time
and i'll have to wait and see how it starts in the morning
right now i'm waiting for the carb cleaner to air out enough that i'm comfortable starting it up to inspect for more leaks
and i'll have to wait and see how it starts in the morning
right now i'm waiting for the carb cleaner to air out enough that i'm comfortable starting it up to inspect for more leaks
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Postmaster
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well its still leaking air, but i can't see fuel anywhere that concerns me. i do plan to replace the rubber parts of the return line from where it leaves the engine to where it goes back to the main line following the frame, there are 2 rubber sections there that are old but no sign of leaking any fuel out.
i also plan to try switching to the other tank tonight and prove its nothing that far back.
if that doesn't do anything, its a new return line kit
i also plan to try switching to the other tank tonight and prove its nothing that far back.
if that doesn't do anything, its a new return line kit
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Posting Guru
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From: Peterborough, Ontario
Remember too that air molecules are smaller than diesel, just because it's not leaking fuel someplace, doesn't mean that air isn't getting in.
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Postmaster
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last night i decided to pour a bottle of ATF (my fuel additive of choice) into the half-full front tank, thinking that any external leaks would then be more obvious with the colored fuel. i poked around a little bit, studied everything i could, and left it on the full rear tank for the night. this morning it fired right up, when i got on the road i switched to the front tank, and noticed that my truck was just a heck of a lot more responsive than it has ever been, more power at less throttle, throttle is almost touchy now.
even with how it started today, i'm ordering return line o-rings, as they're a likely suspect, as well as the old-looking sections of hose between engine and fuel tank. between the two, i should have it solved
even with how it started today, i'm ordering return line o-rings, as they're a likely suspect, as well as the old-looking sections of hose between engine and fuel tank. between the two, i should have it solved
Posting Guru
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From: Peterborough, Ontario
For something local for Viton o-rings, go to a bearing/industrial supplier. They may stock them, or can bring them in for you.
I think the last time I went that route I got 50 for under $10.
I think the last time I went that route I got 50 for under $10.
Posting Guru
Joined: Oct 2005
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From: Oregon
I just got a pack in the mail. McMaster ships fast, worth going that route.
Viton O-Rings for our injectors (#9464K24):
Error On Page
And the olives for the metal line from the filter to IP (#50385K83):
McMaster-Carr
Viton O-Rings for our injectors (#9464K24):
Error On Page
And the olives for the metal line from the filter to IP (#50385K83):
McMaster-Carr
Post Fiend
Joined: Nov 2004
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From: Manitoba
Remember there are seals inside the line caps where the main fuel lines connect to the filter from the lift pump and from the filter to the IP. They wear out/flatten out if over tightened they are available at most diesel shops by line size......
They come in 2 sizes:
1 each .......3/8 ID for the lift pump to filter connection
2 each........5/16 ID for the ends of the filter to IP line
They come in 2 sizes:
1 each .......3/8 ID for the lift pump to filter connection
2 each........5/16 ID for the ends of the filter to IP line
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