Travelling along the A30 towards St Ives a few weeks ago I experienced a sudden internal misting causing instant vision blackout at 70mph. Incredibly hairy moment caused by heater hose failure. I nursed SN55 JPJ for a month waiting for custom silicon hoses. Turned out the middle heater hose had failed for the second time. I noticed that where the heater feed hose goes through the bulkhead, the bulkhead grommet had moved and the metal was razor sharp. This definitely assisted it's demise as the the engine vibrated and chaffed the hose against the bulkhead entry point.
All new blue silicon heater hoses are now installed, but then the issue came up of which antifreeze to use? Water here is soft and the winters are mild so I could almost do without freeze protection, but anti-corrosion is another issue.
All advice most welcome. The silicon hose manufacturer seemed to suggest that an OAT coolant might cause issues with silicone. I'd be grateful for members comments on this.
PS. Where can I get a decent heater valve from? I've gone through two OEM parts at great expense, and they don't seem to work that well anyway. Currently I've taken off the failed A/c compressor and fitted an A/C delete pulley.
I can't find a setting of the system to give me anything except hot air.