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Accidentally poured oil in antifreeze reservoir. Safe to drive short distance after siphon?

Oy! There are about four threads on this subject. Let me see how I can combine…

Sorry. I didn’t know how this site worked exactly and since I wasn’t getting many comments I thought maybe it was because my question in the original post was about something different. My bad

Some people are very particular about what new members post here but don’t worry, the message board isn’t going to overflow and flood the bathroom.

I went through the receipts of all maintenance done by first owner (I am third) and discovered that she was told by dealer 2 years ago that heater core was plugged and she turned it down. She took it in because the heater was not blowing “as hot as it used to”. Does a plugged heater core necessarily mean that you need to replace it? I put this on both my posts

It depends on the nature of the plug up. And assuming it isn’t leaking of course. Sometimes a plugged up one can be back flushed to remove the gunk & returned to service.

It can be backflushed, but I’d recommend that you first determine the source of the gump. After flushing, it should be pressure tested before reinstalling.

Note that it could also be the heater control valve that’s gumped up. It’s mounted on the firewall and diverts the hot coolant through the heater core when you turn the heat on. It too can be flushed, but until you find and correct the source of the gump, there’s no sense flushing the core & valve.

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