Jim Twamely, first let me welcome you to iRV2.com. We are glad to have you join us here. How about introducing yourself in the New Members Check In forum. When you do you can just click on a new discussion instead of a poll. I am sure you will enjoy this website and forums.
You will probably not be able to get the old hose to pull the new hose through as it should be clamped along the way to keep it in place and not get chaffed. Since yours is leaking it sure would not hurt to try. You can certainly by pass the hose or even splice in at each end.
Good luck and keep us posted as to how it goes.
Mike, RVIA & RVSA Certified Master RV Technician
Amy, Dr. Assistant - Roxie & Mei Ling, four legs each
2000 Gulf Stream Scenic Cruiser 450 hp & 1330# torque
06 Saturn Vue, 06 Chevy Z71 4x4 & 2014 Corvette Z51 M7