Is Leaving Distilled Water In Radiator/Block Safe After Flush

[navajochief]

recently flushed out my radiator following instructions on how to flush out Ford's Gold Coolant to convert my '05 F350 6.0L to an ELC brand coolant. I used over 46 gallons of distilled water along with Restore and finishing off with VC9 with yet more flushes to clean out the block and radiator of excess coolant flush. I then ordered a coolant filter from Diesel Site and postponed placing the ELC until I get the coolant filter. I am also changing the thermostat and hoses while I'm at it. My question is it's been close to a week and I left distilled water in the system until today. I drained the block and lower radiator hose as I had been doing during the muliple distilled water flushes I performed. Is leaving the distilled water for long periods of time (5) days in the radiator and engine block allowing for rust to appear? I plan to change the hoses and place concentrate Zerex ELC and top off with distilled water this weekend. I hope I didn't do something I'm going to pay for later in my cooling system. As I mentioned. I used over 40 gallons of distilled water during the process so I'm pretty confident all I have is distilled water in the system. Sorry so long.

[PGreenSVT]

You spent too much money on distilled water. You can do all your cleaning and preliminary rinses with plain tap water. Then flush 3 to 5 times with distilled to get the tap water out. Distilled water should not promote rusting as it has no minerals etc. but it does nothing to protect your engine. There is no reason for waiting to put the ELC in and I recommend you do so immediately. Driving your truck with straight water will allow cavitation when running which will eat away at the internals of your engine.

[navajochief]

Although I left distilled water in the radiator and block for close to week, I wasn't using the truck for commuting. I had the truck sitting in the driveway. I also had removed the thermostat during the flushes and still have the thermostat off. As I mentioned, I emptied out the block and radiator yesterday and the truck is sitting in the driveway until I can get out of work today to starting installing the ELC concentrate. I was just concerned that leaving the water in place and with prolong contact with the metals in the block and radiator, I was promoting rust. And I agree, I used way to much distilled water but at $.98 a gallon, I thought it was well worth cleaning out as much as possible. Thanks again.