Injector return lines

[Redneckgt]

What causes them to pop? Since replacing injectors I've had problems with my left bank. They're getting brittle, I've replaced them with cheapys to the expensive and still they crack and leak.
Any ideas?

 

[Brent@LDS]

You have bought the Brand New Bosch return lines and still having issues?

 

[OregonDMAX]

Are you overtorquing the return line bolts, they are turqued in in/lbs not ft/lbs

I think it's 10 in/lbs if I'm not mistaken

 

[Ne-max]

Are you overtorquing the return line bolts, they are turqued in in/lbs not ft/lbs

I think it's 10 in/lbs if I'm not mistaken

Return lines dont have bolts.

Try quality lines

 

[Redneckgt]

You have bought the Brand New Bosch return lines and still having issues?

Have not found Bosch lines. Have tried products from doorman, sinister, injectors direct etc.

 

[OregonDMAX]

Return lines dont have bolts.

Try quality lines

Shouldn't have assumed, I didn't see it said lbz on the title my bad

 

[ikeG]

Merchant lines are Bosch iirc

Sent from my XT1585 using Tapatalk

 

[PureHybrid]

I know you said they're cracked, but also said they pop? Do you have a clog somewhere in the return system? That will make them blow off.

I'm running cheap plastic Tee's on the injectors with the good braided Gates hose, the cheap hose was cracking like you stated before. Haven't had an issue once putting good hose on.

 

[Brent@LDS]

Have not found Bosch lines. Have tried products from doorman, sinister, injectors direct etc.

Try these lines. OEM Bosch units at a unbeatable price!

http://lincolndieselspecialties.com/i-23846241-oem-bosch-lly-lmm-fuel-return-line-left.html

http://lincolndieselspecialties.com/i-23846240-oem-bosch-lly-lmm-fuel-return-line-right.html

 

[Redneckgt]

I know you said they're cracked, but also said they pop? Do you have a clog somewhere in the return system? That will make them blow off.

I'm running cheap plastic Tee's on the injectors with the good braided Gates hose, the cheap hose was cracking like you stated before. Haven't had an issue once putting good hose on.

they crack and fall apart, eventually pop off and pour diesel everywhere

 

[PureHybrid]

If you don't want to spend $120+ for both Bosch sets, you can get a whole roll of the Gates hose for $50 sometimes cheaper. Part # is 27121 I think.

 

[kidturbo]

If you don't want to spend $120+ for both Bosch sets, you can get a whole roll of the Gates hose for $50 sometimes cheaper. Part # is 27121 I think.

And then sell remainder of the roll to a buddy and recover most of your $50...

:thumb:

 

[PureHybrid]

And then sell remainder of the roll to a buddy and recover most of your $50...

:thumb:

Hey now, only half :hello:

How much of that did you end up using?

 

[Ne-max]

The hose is not the issue. It's the cheap plastic fittings and oring.

 

[kidturbo]

Hey now, only half :hello:

How much of that did you end up using?

I've only used about 10' off that spool so far.


One thing I've learned about rubber fuel lines on diesels, prior to like 2011 much of the OEM stuff wasn't very biodiesel stable. Biodiesel properties will cause some rubber compounds to dry out and crack, and BioD eats natural rubber for lunch.

I ran high percentages of BioD on a couple LLY setups without noting any return line issues. But on the wife's 05 MB CDI, everything besides the injector returns had to be replaced after just a year or so. It's a Euro thing.. Running high percentages of bio is like accelerated testing of the typical 5-20% bio you might be encountering in typical pump diesel.

As mentioned above, on the LBZ you shouldn't have any back pressure on returns. If that's all good, pick a better material. AND make sure it's the correct size line..

 

[tjs82]

If you don't want to spend $120+ for both Bosch sets, you can get a whole roll of the Gates hose for $50 sometimes cheaper. Part # is 27121 I think.

Just did a quick search. Looks like you can still get that hose from certain distributors, but gates doesn't list 5/32" (0.156") ID as a size for that particular hose on their website anymore. I have a feeling gates may have discontinued it. Anyway, I found another type of hose on their site that appears to be identical to the 27121 hose, that they list in 5/32. Same materials, same temp ratings, same biodiesel compatibility, etc. Figured I'd share, just in case the 27121 hose that Jesse recommended becomes hard to find in the future. I posted links for both hoses below, so y'all can compare for yourselves.

Gates PVC/EEC hose (the stuff Jesse runs)
https://www.gates.com/us/en/fluid-power/engine-hose/fuel-line-hose/pvc-eec-fuel-hose/p/p100766/v/233935

Gates standard fuel and oil hose
https://www.gates.com/us/en/fluid-power/engine-hose/fuel-line-hose/standard-fuel-and-oil-hose/p/p100836