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leaking injector line.

blazinzuk

blazinzuk

Buzzbox voodoo
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Is there an o ring where the line screws onto the injector?

I have a leaking injector line. I can't tell exactly where it's coming from. If the O ring on the injector goes bad would it appear as if the leak were coming from the connection of the line to the injector?
 
That's what it looked like can a bad o ring on the injector look like the line is leaking?

I have taken it off and nothing looks wrong with it.
 
I'm not sure Eric, I have had fuel leaks at the injector where the return lines loop from one to the next though. Initially I bought and installed new return lines, and they weren't cheap. Still had leak issues. I eventually bought a rebuilt IP and 8 rebuilt injectors and all the leaks stopped.

I don't know what the injectors look like internally, but I suspect internal leakage of some sort. That might be what you're fighting too.
 
There is a copper ring inside the two halves of the injector where they unscrew..never had any of mine apart,but you can find photos and videos of them apart online..

I had to replace those tiny hoses that loop the return nipples together on my truck--GM gets about 40+ bucks for the hose kit with the itsy-bitsy squeeze clamps,and I had one that came with my Suburban--but I opted to instead use Tygon 1/8" fuel line I got from a mower repair shop,when I read that holds up very well,and needs no clamps..it has worked flawlessly so far,over a year later...

A local diesel mechanic also gave me some Firestone nylon air brake tubing that has a 1/8" I.D.,he uses that on trucks he repairs,he said you must heat the tubing with a heat gun or lighter to soften it enough to push it over the barbs on the injector nipples--once it cools its "permanent" and no clamps are needed...I felt the Tygon was easier to use and it works fine IMO..it'll stand up to diesel and 2 cycle gas mixes better than any rubber line..

I could have sworn my injectors were leaking,or the line was,but it turned out to be that rubber cap on the last injector that blocks the "extra" return nipple off that was cracked and letting diesel pee out...

I used brake cleaner to spray it off and watched carefully after starting it up,and I could finally see where the leak was originating from..
 
diesel4me said:
I could have sworn my injectors were leaking,or the line was,but it turned out to be that rubber cap on the last injector that blocks the "extra" return nipple ..
Click to expand...

Looks like we have a winner folks. After careful investigation it appears to be the rubber nipple on the return that is capped off.
 
Well,that is good news!..at least it'll be a cheap fix..

I just put a machine screw in a short hunk of the Tygon line to use for a "cap" to replace the cracked rubber one--no clamp ,it's never leaked since..used more of the same line to replace some of the other old rubber ones that were ready to fail too...I now carry a few feet of it with me in the glove compartment in case another rubber line decides to fail..

I had a hard time getting at that last injector on the drivers side closest to the firewall to get that "cap" on!..looks easy,but there is a lot of things in the way..finally got it on with some angled needle nosed pliers..
 
I went through this on the passenger side of Big Blue. I simply attached 2' of line to it and connected it to the capped-off nipple on the driver side. Now it looks like a big loop (maybe a "Q" around the engine bay) instead of a big "Y" splitting off the return line. I'm sure you'll be back in business in no time. :)
 
diesel4me said:
I had a hard time getting at that last injector on the drivers side closest to the firewall to get that "cap" on!..looks easy,but there is a lot of things in the way..finally got it on with some angled needle nosed pliers..
Click to expand...

That's the one leaking. Doesn't look like the cap will be here in time so I am gonna do exactly what you did small hose and machine screw
 
I was lucky my truck didn't burn to the ground when it was leaking there!..

At that time,my master cylinder was also dripping brake fluid out of the rear of it where it meets the hydroboost,so when I saw smoke and smelled something ,I assumed it was just the drops of brake fluid that dripped out after sitting several days was just burning off the exhaust--nope!..:eek1:

--I drove it about 6 miles one day,when I stopped a LOT of white smoke came out from under the hood--then I realized it was diesel fuel,I saw the green color from the dye in it..:doah:..

I thought it wasn't GM's best idea to use rubber hose to join the injector returns together,when they are only a few inches away from the exhaust manifolds...:surepal:..but I suppose it does work,and it's cheap..

Another place to get some good hose for the injectors is at a VW dealer--most sell that braided cloth covered rubber hose their TDI's use by the foot..that doesn't really need clamps either,but isn't as easy to install..

I like the Tygon hose better--you can get it at any home center or hardware store,weed eaters and chain saws use it,and 1/8" is a common size...

The guy at the mower shop gave me the last 3 feet off a roll he had for 5 bucks...at Lowes they sell an assortment of sizes in a blister pack for about 3.50...if I were in a real pinch I'd even try the clear vinyl tubing,to get me home...
 
1/8" is what I used,what actual size it is they used originally I dont know,probably metric?..

I had to kind of force it on the barb fittings,I figured a tighter fit would be better seeing I didn't want to mess with the clamps..
 
diesel4me said:
1/8" is what I used,what actual size it is they used originally I dont know,probably metric?..

I had to kind of force it on the barb fittings,I figured a tighter fit would be better seeing I didn't want to mess with the clamps..
Click to expand...

I have broken a nipple off an injector doing this... :doah:


(so take care when forcing things into place) :whistle:
 
The Tygon hose is real soft ,it's only hard to put on because it wants to fold over rather than slide over the barb on the nipple--if your using some hard nylon hose like the air brake hose,the only way you'll get it to slide over the barb would be to heat it up with something like a bic lighter for a few seconds..and it'll be "fun" to push it on before it cools off ,without kinking it..
 
diesel4me said:
I was lucky my truck didn't burn to the ground when it was leaking there!..
Click to expand...

Meh, its diesel. You could spray your @operating temp engine with a super soaker full of diesel and be just fine. Even with it leaking on an exhaust manifold, you'd still need an open flame and the stars to align to ignite it.

:D
 
Yes,but when it's squirting out at 1500 psi,its a lot more likely to combust!..:eek1:...

I recall my dad telling me during WWII they went back to using steam on the aircraft carrier airplane decks,because they tried using hydraulics,and when a few hydraulic hoses happened to burst during a hoisting,the fluid immediately burst into flames and the resulting flamethrower ended up incinerating several crew members!..:eek1:..I guess when it's under 4000 psi,hydraulic fluid ignites like gasoline when it hits the air?...

I was very lucky when my coolant temp switch that runs the injector pump fast idle & advance failed and the wires to it started burning,that I saw the flames before they were able to burn thru the fuel hoses,located about 3" above them!...:eek1:..and all I had to put it out with was spit,my breath,and tossing some dirt on the blazing wires!..:doah:
 
No hydraulic fluid doesnt spontaneously combust. I fix hydraulics every day. Even when it's atomized at high pressure you still need a heat source for ignition.

We have burned down more than a few pieces of equipment with hydraulics bursting and hitting the turbos. Then there's no stopping it.
 
Theres some difference. I remember on the Strykers we had to use (or switch to) a specific hydraulic fluid because of combustion temps/flash points, something like that. Of course, that'd be in an instance where a line burst and shot oil mist on an open flame or something. Those are kinda special circumstances though...

I just remember cause we had like a 250gal tank of fluid in our shop and wondering what the hell we were going to do with the old stuff we weren't allowed to use anymore.
 
If the oil is operating over the flash point temperature that is a design flaw. Many circuits have coolers in the return path. And closed loop circuits are continuously stripping oil off the low side and replenishing with the cooled oil in the charge circuit. If it's still overheating you need bigger coolers and a larger reservoir.
 
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