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Old 10-12-2010, 07:06 PM   #1
GMC87
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Location: N.Canton, Ohio
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Heater control vacuum

Well I think I found my problem tonight as to why my defrost vents will not open.
After reading numerous threads on here I starting checking in the engine bay first, and sure enough there was a vacuum line with a tee sitting wide open with no line to it. One end goes into the fire wall by the heater box the other end goes to a funny looking ball thing about double the size of a softball over by the brake booster.

Now I just have to find a good vacuum port to take of of the engine somewhere and verify that that is it.

Kinda figures the truck came from Alabama and had a new engine put in it, i bet they never even gave a crap about hooking it up.
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Old 10-12-2010, 09:20 PM   #2
motornut
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Re: Heater control vacuum

these may help cover some issues
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Old 10-13-2010, 08:15 AM   #3
GMC87
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Re: Heater control vacuum

The A/C vac line and the big ball is what is not connected to the engine. There is just an open tee back behind the carb. I will try to hook it up tonight and see if that cures it.
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