Problems with new injector lines

I recently replaced the hydraulic head on my m35a2 and at the same time I put all new injector lines. Didn’t really have a choice as all the old lines were rusted and wouldn’t come out. Now every time I crank my truck it blows one of the lines either out of the injector or out of the hydraulic head. It’s happened with every line multiple times and I just cannot figure it out any help with this issue would be greatly appreciated.

Can you post a pictire of the lines you used and of the tips. The Deuce injector line tips are not the standard compression type and they could leak if the end was damaged. As for the line blowing off the end fitting I can not see that happing they way they were designed and put on.

I would agree with the above.
Check that the replacement lines are the Correct one for your application. (Truck/Engine).

Golly, is all the return lines Open all the way back to the fuel tank?
View attachment HH fuel to injectors 11032016.pdf



View attachment fuel system best picture.pdf

If your talking about the injector return lines then yes goes to the overflow valve and back to tank. Does run through the fuel filter over pressure relief valve but back to fuel tank. But don't forget there is no pressure coming out of the injector at the return lines /fitting. Some say they want clear line to see the air in the return lines. They will always look like they have air bubbles and you might not even see any flow with the back pressure from the over flow valve. So you don't need clear nylon tubing cause it will not tell you anything. Thanks for the pics of the injector line fittings as I was looking for them.

(If you are talking the metal lines from the hydraulic head to the injectors) I remember one member replaced his injector lines with NOS parts in the last few years and discovered a couple of them were plugged. I can’t remember who it was but he put a post up about it so try searching.

peashooter said:

(If you are talking the metal lines from the hydraulic head to the injectors) I remember one member replaced his injector lines with NOS parts in the last few years and discovered a couple of them were plugged. I can’t remember who it was but he put a post up about it so try searching.

Click to expand...

I have yet to find that.

If it is blowing the lines out of the nuts, you need to fully seat the lines and tighten them down real tight. It seems like you may not have smashed the ferrules enough to grip the lines and seal.

I would be willing to bet those special end were put on with some kind of a stamping machine at a factory. Not compression fitted. When they work right the end will spin so as not to put a twist in the line when you tighten them down. Also the ones I have done do not need to be over tightened to seat and not leak. Maybe we will get some pictures from the OP and someone has changed the stock lines with different lines and compression fittings.

I've replaced the ends before. They are a 37° flare steel compression ferrule for 1/4" steel line. Get them on McMaster-Carr. Once you squeeze them down they indent the line and they will spin afterward.

Yea heard about the ones you can replace. Maybe that is what someone did. We won't know till he post's a pic or he knows that they have been changed.