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Old 09-23-2015, 03:01 PM   #1
JimmyCriswell
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Location: Mansfield, Texas
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Heater Core Bypassed-still hot air

PO bypassed the heater core on my truck but the floor still seems to be lightly blowing heat into the cab.

What would cause this? I cannot hear the blower motor come on when the switch is is turned on either. I have a lot of diagnosing to do.

I suspect hoses are not connected either possibly. I will attempt to take some pictures tonight.
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Old 09-23-2015, 03:03 PM   #2
michael bustamante
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Re: Heater Core Bypassed-still hot air

youre cowl is putting air into the cab most likely
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Old 09-23-2015, 04:45 PM   #3
Hook'em
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Re: Heater Core Bypassed-still hot air

Quote:
Originally Posted by JimmyCriswell View Post
PO bypassed the heater core on my truck but the floor still seems to be lightly blowing heat into the cab.

What would cause this? I cannot hear the blower motor come on when the switch is is turned on either. I have a lot of diagnosing to do.

I suspect hoses are not connected either possibly. I will attempt to take some pictures tonight.
Texas is likely the cause - 90+ degrees on the first day of Fall. Like Michael said, outside air is coming probably coming in through the cowl.

The outside air door is controlled with vacuum lines. It might be a good idea to check the vacuum system to make sure everything is opening and closing correctly. There is a diagram of the vacuum lines in this thread.

Andy4639 usually chimes in to these threads with good information.
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Last edited by Hook'em; 09-23-2015 at 04:56 PM.
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Old 09-23-2015, 08:53 PM   #4
BrianG
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Re: Heater Core Bypassed-still hot air

Quote:
Originally Posted by Hook'em View Post
Texas is likely the cause - 90+ degrees on the first day of Fall. Like Michael said, outside air is coming probably coming in through the cowl.

The outside air door is controlled with vacuum lines. It might be a good idea to check the vacuum system to make sure everything is opening and closing correctly. There is a diagram of the vacuum lines in this thread.

Andy4639 usually chimes in to these threads with good information.
No vacuum operated system if it is not an air conditioned truck, just so you know... I guess unless someone added it.
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