I replaced one of the heater cores rubber hoses and in doing so i cracked the
stem at the firewall. I know to replace the heater core requires removeing the dash etc. Has anyone been able to splice the plastic heater core tubing?

Thank You

I've never tried this, but I'd get a fiberglassing kit that you use for repairing boat hulls and use the combination of epoxy and fiber sheet. Another possibility would be to use Aralydite (sp?) fast-weld 10 epoxy. It's about the best epoxy that I've ever used, it's just not clear.