Easiest way to find fuel system leaks is to pressurize the fuel tank to 10 psi max then go hunting.
I use an old fuel cap with an air chuck tapped in but a blow gun wrapped in a rag works also except then it takes another person to do the hunting.
Only leak this won't find is if it's inside the fuel tank which does happen.
Good reading> http://www.cumminsforum.com/forum/94...m-writeup.html

 

wow...neat diagram...thankyou!

so.....if the line visually looks to be OK, should I replace it anyways???

 

Might not be a bad idea. You might see a wet spot on it somewhere, or if you flex it in your hands, you might see some cracks open up. I've seen it on many 2nd gens, so it's worth throwing one on as a preventive measure. The return hose is 5/16" diameter, and I think around 18" long.

 

OK...
I think I will change it out. Thanks for the info on sizes