I keep replacing crush washers on my fuel line by the injection pump. Works for a day or two then starts to sputter on idle. The manual fuEl primer then won't hold pressure and when you push on the plunger you can heear air escaping from the lines. I've now replaced almost every fuel line and the problem will come back. After I replace the crush washers the primer will hold pressure for a couple days again. Weird thing is when the problem comes back it's only on cold starts. Once it's warmed up the issue goes away. Any ideas before I keep tgrowing fuel lines at it
Check valve on the return line at the injector pump is hanging open?
How would I check that? Does that explain it being intermittent?
Have you checked the seats on the fuel pump ,banjo fitting and banjo bolt to see if they are ok ? Your not crushing the crush washers to much and cracking them?
I've found the best way to tighten banjo bolts is to tap the wrench with your palm in an gentle impact fashion, seems to crush and seal better. They don't need much torque.
Are you using the correct washer for the style of bolt you have? Washers with the viton seal must have a bolt with flat flange under the head and solid washer require a bolt with a stepped flange. Also using plain old copper washers out of the hardware assortment does not always hold up well.