Leaking heater core?

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Norwester

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Battle Ground, WA
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David
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1986
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C-10
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350
My '86, with a/c, was backed into my driveway which is sloped, meaning the front was slightly down.

Engine was running with the heater going. I noticed a fairly slow water drip coming off my a/c evaporator housing. Guess I should mention that the a/c is totally disconnected.

I don't drive the truck a great deal, maybe 300 miles per month. I've had it for about a year and about once every 6 weeks, I put maybe a pint of coolant in.

I'm assuming I need a heater core but before I delve into it, is there another thing to check?

I've never detected coolant inside the cab. Everythng is dry.

What do you think...is a new heater core in my future?

Thanks in advance.

Edit: I just went out and brought the engine up to temp and turned on the heat. I couldn't find any water dripping so maybe it was just the rainwater finding a path down. Think I'll just keep an eye on it.
 
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chengny

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I couldn't find any water dripping so maybe it was just the rainwater finding a path down. Think I'll just keep an eye on it.

Thatta boy! You're doing it right. There's no need to go looking for trouble - it usually finds you.
 

HotRodPC

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My '86, with a/c, was backed into my driveway which is sloped, meaning the front was slightly down.

Engine was running with the heater going. I noticed a fairly slow water drip coming off my a/c evaporator housing. Guess I should mention that the a/c is totally disconnected.

I don't drive the truck a great deal, maybe 300 miles per month. I've had it for about a year and about once every 6 weeks, I put maybe a pint of coolant in.

I'm assuming I need a heater core but before I delve into it, is there another thing to check?

I've never detected coolant inside the cab. Everythng is dry.

What do you think...is a new heater core in my future?

Thanks in advance.

Edit: I just went out and brought the engine up to temp and turned on the heat. I couldn't find any water dripping so maybe it was just the rainwater finding a path down. Think I'll just keep an eye on it.

Yes, I was going to say, probably water out of the cowl if it's just water. If it's antifreeze or rusty water, then you have reason to wonder about the heater core.
 

Stepside Billy

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If it was the heater core you would smell anti-freeze in the truck.
 

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